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1
Sakaguchi, Masakazu. "Gasification of bio-oil and bio-oil/char slurry." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/23347.
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Economic utilization of biomass as a fuel has been limited by transportation cost. One suggested remedy to address the problems of processing biomass on a large scale is to pyrolyze solid biomass at numerous local sites and transport the resulting liquid or liquid/char slurry to a large centralized conversion plant. This research involves the gasification of biomass fast pyrolysis oil, so called bio-oil, and a slurry mixture of bio-oil and fast pyrolysis char into synthesis gas.
Kinetics of the reaction of steam with chars was studied using a thermo-gravimetric analyzer. Slurry Char was produced by pyrolysis of an 80 wt% bio-oil/20 wt% char mixture at nominal heating rates of 100–10,000°C/s. The resulting Slurry Char was subjected to steam gasification with 10–50 mol% steam at 800–1200°C. Reactivity of the Slurry Chars increased with the pyrolysis heating rate, but was lower than that of Original Chars. Kinetic parameters were established for a power-law rate model. Some measurements were initially done of gasification in CO₂.
A fluidized bed reactor, equipped with an atomization system, was constructed for gasification of bio-oil and slurry. The reactor contained either sand, or Ni-based catalyst. Experiments included gasification with pure steam and air. Effects of bed temperatures in the range 720–850°C, steam-to-carbon molar ratios of 2.0–7.5, and air ratios of 0–0.5 on gas composition and yields were tested. The carbon conversion of bio-oil to gas was found to be greater than that of slurry. The product gas composition was affected significantly by catalysis of the water-gas shift and the steam gasification. Greater yields of hydrogen and lesser yields of CO and hydrocarbons were found when catalyst was used. On a dry, inert-free basis, gases of up to 61% H₂ were obtained. The data were compared with a thermodynamic equilibrium model. The product gas yield was reasonably predictable by the model.
A mass and energy balance model of steam gasification in a dual-bed gasifier-combustor revealed that energy requirements are sensitive to the steam/carbon ratio and to the recovery of latent heat in the produced gas.
2
Zhang, Mingming. "Properties of bio-oil based fuel mixtures: biochar/bio-oil slurry fuels and glycerol/bio-oil fuel blends." Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/1825.
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This thesis reports the properties of bio-oil-based fuel mixtures. For bioslurry fuels, the interaction between biochar and bio-oil results in changes in fuel properties and the redistribution of inorganic species. For glycerol/methanol/bio-oil (GMB) fuel blends, the solubility and fuel properties are improved upon methanol addition but other impurities in crude glycerol worsen the solubility with limited impact on properties. It is also possible to integrate the GMB blends production into the biodiesel production process.
3
Ortiz-Toral, Pedro J. "Steam reforming of bio-oil effect of bio-oil composition and stability /." [Ames, Iowa : Iowa State University], 2008.
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Pollard, Anthony Joseph Sherwood. "Comparison of bio-oil produced in a fractionated bio-oil collection system." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1474690.
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Atiku, Farooq Abubakar. "Combustion of bio-oil and heavy fuel oil." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/12179/.
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The use of combustion parameters to predict what happens to fuel during burning and its effect on living systems is important. This work is directed towards understanding the fundamental chemistry of soot generated from burning biomass-pyrolysis liquid fuels and its mechanism of formation. In this study, fuels such as eugenol, anisole, furfural and some hydrocarbon fuels are subjected to combustion using a wick burner which allowed the burning rate, smoke point and emission factor to be investigated. Reaction zone analysis of flames by direct photography and by using optical filters for further investigation of C2* and CH* species, was conducted. Additionally, detailed characterization of the soot generated was performed, and comparisons were made with soot from petroleum products and from biomass combustion system. The key aim was to generate experimental data and to capture detailed information regarding sooting tendencies with a view to utilize the information which would eventually allow the formation of a comprehensive bio-oil combustion model. This could provide accurate predictions of the combustion characteristics and pollutant formation. Studies are reported on the significant role of high temperature pyrolysis products in soot formation and acquiring further mechanistic insight. This work has been extended to consider heavy petroleum fuel oils (residual oil) during combustion and the effect of composition on combustion products and on the effect on health and the global environment. Heavy fuel oil, such as Bunker C and vacuum residue, are commonly used as fuel for industrial boilers, power generation, and as transport fuels in, for example, in large marine engines. The combustion of these fuels gives rise to carbonaceous particulate emissions including fine soot (Black Carbon or BC) which, along with associated polynuclear aromatic hydrocarbons (PAH): The structure and thermal reactions of petroleum asphaltene have been studied by analytical pyrolysis. Additionally, related combustion characteristics of the asphaltene extracted from bio-oil have been investigated by pyrolysis gas chromatography-mass spectrometry. The results showed the difference between bio-asphaltene and the petroleum asphaltene and the different tendency to form smoke. They also showed the presence of markers for the bio-asphaltene structure.
6
Chan, Jacky. "Ethanol production from bio-oil." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/14730.
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Bioethanol is often viewed as one of the solutions to the tight gasoline supplies in North America. Although bioethanol is already available in the market, there are a number of problems associated with the current processes for the production of bioethanol. The current bioethanol production processes are often referred as first generation bioethanol production processes. For these first generation processes, the feedstocks for production
are usually energy crops. The most common energy crops in North America are corn and
wheat. The use of these energy crops has triggered debates on the problems associated
with using food sources to create energy and the uptake of agricultural land to produce
energy. In this project, an alternative feedstock for bioethanol is investigated. The
feedstock used in the project is bio-oil, which can be derived from any biomass waste. An advantage of using bio-oil is that it is not derived from food crops but instead waste
material is being converted into energy. The objective of this study was to determine the technical viability of producing bio
ethanol using bio-oil as a substrate for fermentation. In order to maximize the ethanol yield, the extraction of levoglucosan with water was optimized and a number of detoxification techniques for inhibitor removal were evaluated. This report provides a technical overview of conditions evaluated for extracting levoglucosan from bio-oil, and methods used for improving the fermentability of bio-oil hydrolysate by detoxification. The techniques used in an attempt to improve the fermentability of bio-oil hydrolysate
include: adsorption, overliming, solvent extraction, and hydrogenation. In addition, a
biological approach called adaptive evolution was used to aid the yeast to adapt to the inhibitory environment of bio-oil hydrolysate in order to increase their resistance to inhibitors. The optimal condition for aqueous extraction of levoglucosan from bio-oil was found to
be 1:1 (mass water to mass bio-oil). It was found that the temperatures examined (25°C
and 80°C) had minimal effect on the amount of levoglucosan extracted. Among the detoxification techniques tested, it was found that overliming and solvent extraction were able to improve the fermentability of bio-oil hydrolysates. Overliming was able to
increase the yield of ethanol from bio-oil hydrolysate by 0.19±0.01 (g ethanol/g glucose) at 50% strength hydrolysate and 0.45±0.05 (g ethanol/g glucose) at 40% strength hydrolysate. A number of extractants were examined and the three best solvents were 25% volume of tri-n-octylamine with co-solvent 1-octanol, 50% volume of alamine 336 with co-solvent 1-octanol and oleyl alcohol. These three solvents were able to selectively remove at least 84 —
93% of acetic acid, which was the targeted inhibitor in bio-oil hydrolysate. In addition, a technique called adaptive evolution of yeasts was applied, which was capable of increasing the ethanol yield by at least 6% when compared with the
unadapted parental strains.
7
Lifita, Nguve Tande. "Autothermal reforming of bio-oil model compounds." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/20004/.
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Correll, David. "Optimized landscape plans for bio-oil production." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1464191.
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9
Liu, Kai. "Catalytic hydrodeoxygenation of bio-oil and model compounds." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/51555.
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The upgrading of the Norwegian spruce derived bio-oil was carried out in a batch reactor with conditions of 50 bar H2 (cold) and 3 to 13 hr of batch time at 175 to 250 ℃. The emphasis was given on the effect of operating conditions on the hydrodeoxygenation (HDO) performance of unsupported NiMo nano sulphide catalysts. It is found that the degree of deoxygenation of the bio-oil increases and that of hydrogenation of the upgraded products declines with increasing the reaction temperature. The addition of sulphur to prevent the nanosulphide catalyst leaching problem is not essential. Extending the batch time produces more saturated products with less oxygen content, but it can be optimised as the deoxygenation reaction rate decreases along the time. As for HDO solvent, dodecane is preferred comparing with tetralin. The HDO of p-cresol over Co/Al2O3 and Ni/Al2O3 catalysts at 250 to 375 ℃ and 50 bar of H2 (hot) in a batch reactor gives 4-methylcyclohexanol, methylcyclohexane and toluene as the major products. Both catalysts are active leading to almost complete conversion (≥98%) of p-cresol at all temperatures. The degree of deoxygenation and the product distribution of toluene increases with temperature. Toluene can be produced by the direct deoxygenation of p-cresol and by the disproportionation of methylcyclohexenes at high temperature (i.e. 375 ℃). Sulphur suppresses the HDO of p-cresol. It deactivates the hydrogenation sites but does not appear to be a poison for the hydrogenolysis sites. Same conditions were used for the HDO of guaiacol, except the H2 pressure being used was 40 bar (cold). Dominant products are cyclohexanol, methoxycyclohexanols and cyclohexane at 300 ℃ and below and those at 325 ℃ and above are cyclohexane, benzene and ring contraction products (i.e. cyclopentane and methylcyclopentane). High temperatures facilitate deoxygenation and benzene production. As the temperature increases, the methoxyl group is firstly removed and then the hydroxyl group. At 350 ℃, reducing the pressure from 40 bar (cold) to 20 bar (cold) increases the benzene product distribution from 2 wt% to 40 wt%. Sulphur has a detrimental effect on the HDO of guaiacol. Catechol is the main product from guaiacol in the presence of sulphur.
10
Thanamongkollit, Narin. "Modification of Tung Oil for Bio-Based Coating." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1218080747.
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11
Wauts, Johann André. "Catalytic microwave pyrolysis to produce upgraded bio-oil." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/61344.
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To assess the performance and future possibilities of catalytic microwave pyrolysis, laboratory-scale experiments were conducted on a widely available biomass feedstock, Eucalyptus grandis. Non-catalysed microwave pyrolysis was conducted under varying conditions to determine important factors of the microwave pyrolysis process and to conduct a basic performance evaluation. Future possibilities of microwave pyrolysis were determined by comparison to available technologies. Calcined Mg-Al LDH clay (layered double oxide or LDO) was used as catalyst to improve the quality of the pyrolysis process and its products. The heating and reaction mechanisms for microwave pyrolysis show that it offers distinct advantages over conventional pyrolysis. The main advantages are rapid and efficient volumetric heating, as well as acceptable yields at lower temperatures (much lower than those required by conventional pyrolysis), which can possibly lead to significant energy savings.
Comparing the performance of a modified domestic microwave to an off-the-shelf microwave unit (Roto Synth) proved that cheap and comparative microwave research is possible. The yields from the domestic microwave products compared very closely to those of the Roto Synth unit, each having yields for char, oil and gas of 47.9%, 33.2%, 18.9% and of 46.8%, 32.7%, 20.55% respectively. The cost of the modified domestic setup was ~1% of that of the off-the-shelf unit. The use of a quartz reactor and slight adjustments to the stepper motor driver and thermocouple are recommended for future use.
The pyrolysis process was found to be very dependent on power and power density. Higher powers increase the liquid and gas yields and a critical power density was identified between 800W and 1000W. The effects of power density were interesting and led to conclusions regarding the penetration depth of microwaves which could possibly play a significant role in the scale-up of microwave pyrolysis technology.
Microwave pyrolysis undeniably has several advantages over conventional pyrolysis. However, for it to become competitive, microwave fast pyrolysis technologies need to be developed through the use of mixed bed reactors that can achieve fast heating rates. Possible candidates include rotating cone and fluidised bed reactors. Hybrid technology also provides unique advantages and has huge potential. Comparison of pyrolysis technologies is difficult without good data on continuous microwave pyrolysis reactors, and therefore the development of such reactors is recommended for future research.
Catalysis of microwave pyrolysis with LDO proved effective. The catalyst promoted the formation of volatiles (gas and liquid), even when present in small ratios. It also promoted the formation of esters and even anhydrides and small fractions of hydrocarbons at high catalyst ratios. The catalyst activity led to increased water yields. This indicated that it removes oxygen from the pyrolysis products, thereby improving their quality. The catalyst was believed to be limited by the low temperatures used in this investigation and higher temperatures might increase the release of CO2 and should be investigated. Significant reduction in the total acid number (TAN) and an improved dry-basis heating value were also achieved by the addition of the catalyst. The water content increased from 50% to 70%, the TAN reduced from 174 mg KOH/(g oil) to 72 mg KOH/(g oil), and the calorific value increased from 19.1 MJ/kg to 21.5 MJ/kg.Dissertation (MEng)--University of Pretoria, 2017.
Chemical Engineering
MEng
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12
Supanchaiyamat, Nontipa. "Bio-based thermoset composites from epoxidised linseed oil." Thesis, University of York, 2012. http://etheses.whiterose.ac.uk/3265/.
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Bio-based thermoset composites were prepared from epoxidised linseed oil (ELO) using bio-derived crosslinkers. The use of Pripol 1009 (a dimerised fatty acid derived from natural oils and fats) as a crosslinker yielded homogenous transparent films. The inclusion of catalysts, in particular, 4-dimethylaminopyridine (DMAP), demonstrated a significant improvement in the mechanical properties of the resins. An infrared spectroscopic study coupled with modulated differential scanning calorimetry revealed the epoxide ring opening, followed by etherification occurred during the curing process. The optimum DMAP catalyst loading was 0.5-1 % with respect to the total resin weight. The optimised formulation consisting of ELO, Pripol and DMAP were subsequently combined with starch or modified starch in order to improve the resin properties. Normal corn starch, high amylose corn starch and their acid hydrolysed derivatives were included in the formulation. The addition of starch improved the mechanical properties of the films with high amylose starch yielding a film with the most desirable properties. Expansion of high amylose corn starch (gelatinisation and retrogradation) yielded a high surface area material. The formulation with 20% wt. of gelatinised starch yielded a film with 227% improvement in tensile strength and 166% enhancement in Young’s modulus, compared to those with no added starch. Moreover, expanded starch granules uniformly dispersed in the polymer matrix, resulting in a complete disappearance of phase separation. This was attributed to better interfacial adhesion of porous expanded starch and the polymer matrix. Thermal analysis revealed retardation in the cure process in the presence of starch, however the hydroxyl groups of starch were likely to enhance the extent of curing, as indicated by the higher total enthalpy of reaction. Furthermore, these bio-based composites demonstrated excellent thermal stability. Esterification of expanded starch dramatically decreased the water uptake of the resins however, the mechanical properties were compromised, owing to low thermal stability of the esterified starch.
13
Wang, Yi. "Transformation of bio-oil during pyrolysis and reforming." Thesis, Curtin University, 2012. http://hdl.handle.net/20.500.11937/676.
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The pyrolysis of biomass is a very effective means of energy densification. With the bio-char returned to the field as a soil conditioner and for carbon bio-sequestration, bio-oil can be used in many ways, including being upgraded into liquid transport biofuels or being used as a feedstock for gasifiers or conventional boilers. However, a number of technical challenges exist during bio-oil applications, such as formation of tar and coke. The fundamental understanding on the transformation of bio-oil under various thermal chemical conversion conditions is essential for the development of novel technologies for the clean utilisation of bio-oil.Thermal decomposition (pyrolysis) is always the first step in all thermal chemical processes involving bio-oil. The pyrolysis of bio-oil and its separated fractions was carried out in a novel two-stage fluidised-bed/fixed-bed quartz reactor. The results indicated that bio-oil was exceedingly reactive and underwent drastic changes when it was further heated. The evolution of various complex aromatic ring systems was tightly related to the formation of coke and tar. The interactions among the different chemical groups of the bio-oil constituted a unique thermal behaviour of bio-oil.The behaviour of bio-oil during reforming was studied. The non-catalytic/catalytic steam reforming of above feedstock was conducted respectively. Without catalysts, extra steam supply showed limited effects on tar reforming. Char-supported iron catalyst showed good performance on the reforming of tars produced from the thermal cracking of the bio-oil and its components with steam. The catalytic steam reforming showed obvious effects on the conversion of non-aromatics (e.g. sugars), particularly the large molecules at low temperatures (< 700 °C). With increasing temperature, the catalyst showed good performance on the reforming of aromatic ring systems. The interactions among the species degraded from lignin and cellulose/hemicellulose obviously affected the evolution of aromatic structures during the catalytic steam reforming of bio-oil. The main possible role played by cellulose/hemicellulose-derived species was the provision of additional radicals during the reforming of bio-oil.
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Kadarwati, Sri. "Coke Formation during the Hydrotreatment of Bio-oil." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/51889.
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Pyrolysis-biorefinery shows great promise for the production of liquid fuels and chemicals from non-food lignocellulosic biomasses. Coke formation and catalyst deactivation are among the biggest challenges facing the technology development. This study investigated the formation of coke during the hydrotreatment of bio-oil from the pyrolysis of mallee wood. Bio-oil with externally added sugars and phenolic compounds was also hydrotreated to gain better understanding about the reactions involved in coke formation.
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Wang, Hongqi. "Bio-oil Upgrading via High-Pressure Reactive Distillation." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/82786.
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This study aims to investigate the roles of process parameters especially pressure and the major components in the high-pressure reactive distillation of bio-oil. The bio-oil distillation fraction yields and properties were evaluated to demonstrate the advantages of the distillation at elevated pressures over distillation at atmospheric pressure. The results indicate that high-pressure distillation can achieve high distillate yields with reduced polymerisation because high pressure can retain water and other light components in the liquid phase.
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Rückert, Marcel, Katharina Schmitz, and Hubertus Murrenhoff. "Comparison of Heat-Properties and its Implications between Standard-Oil and Bio-Oil." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200109.
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An important criteria for optimising hydraulic systems is their size. Especially for tanks and heat exchangers oil parameters as heat capacity and thermal conductivity have a big influence on the size. Additionally, various oils differ in their parameters. Accordingly, the heat capacity and thermal conductivity need to be known. However, little research has been done. Data-sheets usually do not provide any thermal data. In this paper, the thermal conductivity is measured for varying types of hydraulic oils. The thermal conductivity is determined by a newly designed test-rig measuring the radial temperature difference in a tube at a quasi-static state using a constant heat flux. Thus, an overview over the thermal conductivity of different oils is achieved. Based on the results, a comparison between different types of fluid is made.
17
Liu, Peiyan. "Improvement of bio-oil stability in wood pyrolysis process." Thesis, Aston University, 2003. http://publications.aston.ac.uk/10065/.
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Pyrolysis is one of several thermochemical technologies that convert solid biomass into more useful and valuable bio-fuels. Pyrolysis is thermal degradation in the complete or partial absence of oxygen. Under carefully controlled conditions, solid biomass can be converted to a liquid known as bie-oil in 75% yield on dry feed. Bio-oil can be used as a fuel but has the drawback of having a high level of oxygen due to the presence of a complex mixture of molecular fragments of cellulose, hemicellulose and lignin polymers. Also, bio-oil has a number of problems in use including high initial viscosity, instability resulting in increased viscosity or phase separation and high solids content. Much effort has been spent on upgrading bio-oil into a more usable liquid fuel, either by modifying the liquid or by major chemical and catalytic conversion to hydrocarbons. The overall primary objective was to improve oil stability by exploring different ways. The first was to detennine the effect of feed moisture content on bio-oil stability. The second method was to try to improve bio-oil stability by partially oxygenated pyrolysis. The third one was to improve stability by co-pyrolysis with methanol. The project was carried out on an existing laboratory pyrolysis reactor system, which works well with this project without redesign or modification too much. During the finishing stages of this project, it was found that the temperature of the condenser in the product collection system had a marked impact on pyrolysis liquid stability. This was discussed in this work and further recommendation given. The quantity of water coming from the feedstock and the pyrolysis reaction is important to liquid stability. In the present work the feedstock moisture content was varied and pyrolysis experiments were carried out over a range of temperatures. The quality of the bio-oil produced was measured as water content, initial viscosity and stability. The result showed that moderate (7.3-12.8 % moisture) feedstock moisture led to more stable bio-oil. One of drawbacks of bio-oil was its instability due to containing unstable oxygenated chemicals. Catalytic hydrotreatment of the oil and zeolite cracking of pyrolysis vapour were discllssed by many researchers, the processes were intended to eliminate oxygen in the bio-oil. In this work an alternative way oxygenated pyrolysis was introduced in order to reduce oil instability, which was intended to oxidise unstable oxygenated chemicals in the bio-oil. The results showed that liquid stability was improved by oxygen addition during the pyrolysis of beech wood at an optimum air factor of about 0.09-0.15. Methanol as a postproduction additive to bio-oil has been studied by many researchers and the most effective result came from adding methanol to oil just after production. Co-pyrolysis of spruce wood with methanol was undertaken in the present work and it was found that methanol improved liquid stability as a co-pyrolysis solvent but was no more effective than when used as a postproduction additive.
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Pattiya, Adisak. "Catalytic pyrolysis of agricultural residues for bio-oil production." Thesis, Aston University, 2007. http://publications.aston.ac.uk/9804/.
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Agricultural residues from Thailand, namely stalk and rhizome of cassava plants, were employed as raw materials for bio-oil production via fast pyrolysis technology. There were two main objectives of this project. The first one was to determine the optimum pyrolysis temperature for maximising the organics yield and to investigate the properties of the bio-oils produced. To achieve this objective, pyrolysis experiments were conducted using a bench-scale (150 g/h) reactor system, followed by bio-oil analysis. It was found that the reactor bed temperature that could give the highest organics yield for both materials was 490±15ºC. At all temperatures studied, the rhizome gave about 2-4% higher organics yields than the stalk. The bio-oil derived from the rhizome had lower oxygen content, higher calorific value and better stability, thus indicating better quality than that produced from the stalk. The second objective was to improve the bio-oil properties in terms of heating value, viscosity and storage stability by the incorporation of catalyst into the pyrolysis process. Catalytic pyrolysis was initially performed in a micro-scale reactor to screen a large number of catalysts. Subsequently, seven catalysts were selected for experiments with larger-scale (150 g/h) pyrolysis unit. The catalysts were zeolite and related materials (ZSM-5, Al-MCM-41 and Al-MSU-F), commercial catalysts (Criterion-534 and MI-575), copper chromite and ash. Additionally, the combination of two catalysts in series was investigated. These were Criterion-534/ZSM-5 and Al-MSU-F/ZSM-5. The results showed that all catalysts could improve the bio-oils properties as they enhanced cracking and deoxygenation reactions and in some cases such as ZSM-5, Criterion-534 and Criterion-534/ZSM-5, valuable chemicals like hydrocarbons and light phenols were produced. The highest concentration of these compounds was obtained with Criterion-534/ZSM-5.
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Wikberg, Elena. "Catalytic Upgrading of Fast Pyrolysis Bio-oil Using Zeolites." Thesis, KTH, Kraft- och värmeteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255683.
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Fast pyrolysis bio-oil is considered as a possible source for production of liquid bio-fuels and bio-chemicals enabling the necessary transition to a renewable energy system. In this Master’s thesis work the upgrading of fast pyrolysis bio-oils with Fluid Catalytic Cracking (FCC) conversion process at industrially relevant conditions is studied using Fluid Catalytic Cracking Micro Activity Test (FCC MAT) unit at RISE ETC in Piteå, Sweden. The study is focused on evaluating the process in terms of production of value-added products including petrochemical materials, such as propylene and benzene, toluene, xylene (BTX), and petroleum range liquid biofuels. The evaluation of the process was based on the upgraded products yield and quality characterized by the chemical composition of collected liquid and gas samples with regards to several influencing factors including origin of the bio-oil, addition of ZSM-5 zeolite to the commercial catalyst and FCC operation parameters, such as reaction temperature, catalyst to oil (CTO) ratio and ZSM5 zeolite catalysts acidity. Several analytical methods were applied for characterization of both feedstock and products, including GC MS analysis and determination of the boiling range distribution of the liquid products by simulated distillation. The results of this work showed that the process of upgrading pure pyrolysis bio-oil was challenging and required further studies to develop a practical operating process. While the process of co-feeding of the pyrolysis bio-oil with commercial FCC fossil feedstock was determined as feasible at industrially relevant conditions. Catalytic conversion of co-fed pyrolysis bio-oil at the ratio of 20/80 resulted similar petrochemical products to commercial fossil feedstock with full deoxygenation of pyrolysis bio-oil. Moreover, the results showed that high catalytic reaction activity conditions with high reaction temperature along with the use of ZSM-5 zeolite were favored for maximizing the BTX and gasoline range products.Snabb pyrolys bio-olja betraktas som en möjlig källa för produktion av flytande biobränslen och biokemikalier som möjliggör den nödvändiga övergången till ett förnybart energisystem. I detta examensarbete studeras uppgraderingen av snabba pyrolys bio-oljor med FCC MAT-enheten vid RISE ETC i Piteå, Sverige. Studien är inriktad på att utvärdera processen inom ramen för produktion av mervärdesprodukter inklusive petrokemiska material, såsom propen och bensen, toluen, xylen (BTX) och flytande biobränslen. Utvärderingen av processen baserades på det uppgraderade produktutbytet och kvaliteten som kännetecknades av den kemiska sammansättningen av uppsamlade vätske- och gasprover med avseende på flera påverkande faktorer inklusive bio-oljans ursprung, tillsättningen av ZSM-5 zeolit till den kommersiella katalysatorn och FCC-driftparametrar, såsom reaktionstemperatur, förhållandet katalysator till olja (CTO) och ZSM-5 zeolitkatalysatorers surhet. Flera analysmetoder användes för karaktärisering av både råmaterial och produkter, inklusive GC MS-analys och bestämning av kokpunkternas fördelning av de flytande produkterna genom simulerad destillation. Resultaten av detta arbete visade att processen för uppgradering av ren pyrolys bio-olja var utmanande och kräver ytterligare studier för att utveckla en praktisk driftsprocess. Medan processen för sam-matning av pyrolys bio-olja med kommersiell FCC-fossil råvara bestämdes vara genomförbar vid industriellt relevanta förhållanden. Katalytisk omvandling av sam-matad pyrolys bio-olja i förhållandet 20/80 resulterade i liknande petrokemiska produkter som kommersiellt fossilt råmaterial med full deoxygenering av pyrolys bio-oljan. Resultaten visade dessutom att förhållanden med hög katalytisk reaktionsaktivitet och hög reaktionstemperatur tillsammans med användning av ZSM-5-zeolit var gynnsamma för att maximera produktionen av mervärdesprodukter såsom BTX- och biobränslen.
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Wu, Liping. "Acid-catalysed reactions of bio-oil in liquid phase." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/48903.
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Under acid-catalysed condition, the behaviour of different components in bio-oil with alcohols or water was investigated. Heavy carboxylic acids and phenolics in bio-oil were quantified. The reaction routes of typical components including carboxylic acids and phenolics were distinctly different in alcohols and water. The coke formation during this process varied with different experimental parameters. Two types of acid catalysts, mineral acid and solid acid, had different effects on the acid-treatment of bio-oil.
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Maqbool, Wahab. "Supercritical carbon dioxide extraction and fractionation of bio-oil." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/134415/1/Wahab_Maqbool_Thesis.pdf.
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In this study a supercritical fluid extraction process using carbon dioxide as a solvent was developed and investigated as a potential energy efficient and cost effective alternative to conventional distillation for the extraction and subsequent fractionation of high value renewable chemicals from lignocellulosic bio-oil. Fundamental solubility studies utilizing both laboratory and pilot infrastructure were completed, and equation of state modelling and process simulations developed for the first time for this supercritical fluid extraction process. Techno-economic evaluation of the processes revealed that supercritical fluid extraction of bio-oil is a competitive alternate to conventional distillation process.
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Mohammed, Isah Yakub. "Pyrolysis of Napier grass to bio-oil and catalytic upgrading to high grade bio-fuel." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39572/.
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Biomass is one of the renewable energy resources that has carbon in its building blocks that can be processed into liquid fuel. Napier grass biomass is a herbaceous lignocellulosic material with potentials of high biomass yield. Utilization of Napier grass for bio-oil production via pyrolysis is very limited. Bio-oil generally has poor physicochemical properties such as low pH value, high water content, poor chemical and thermal stabilities which makes it unsuitable for direct use as fuel and therefore requires further processing. Upgrading of bio-oil to liquid fuel is still at early stage of research. Several studies are being carried out to upgrade bio-oil to transportation fuel. However, issues regarding reaction mechanisms and catalyst deactivation amongst others remain a challenge. This thesis gives insights and understanding of conversion of Napier grass biomass to liquid biofuel. The material was assessed as received and characterized using standard techniques. Pyrolysis was conducted in a fixed bed reactor and effect of pyrolysis temperature, nitrogen flow rate and heating rate on product distribution and characteristics were investigated collectively and pyrolysis products characterized. Effects of different aqueous pre-treatments on the pyrolysis product distribution and characteristics was evaluated. Subsequently, in-situ catalytic and non-catalytic, and ex-situ catalytic upgrading of bio-oil derived from Napier grass using Zeolite based catalysts (microporous and mesoporous) were investigated. Upgraded bio-oil was further fractionated in a micro-laboratory distillation apparatus. The experimental results showed that high bio-oil yield up to 51 wt% can be obtained from intermediate pyrolysis of Napier grass at 600 oC, 50 oC/min and 5 L/min nitrogen flow in a fixed bed reactor. The bio-oil collected was a two-phase liquid, organic (16 wt%) and aqueous (35 wt%) phase. The organic phase consists mainly of various benzene derivatives and hydrocarbons while the aqueous phase was predominantly water, acids, ketones, aldehydes and some phenolics and other water-soluble organics. Non-condensable gas (29 wt%) was made-up of methane, hydrogen, carbon monoxide and carbon dioxide with high hydrogen/carbon monoxide ratio. Bio-char (20 wt%) was a porous carbonaceous material, rich in mineral elements. Aqueous pre-treatment of Napier grass with deionized water at severity factor of 0.9 reduced ash content by 64 wt% and produced bio-oil with 71 % reduction in acid and ketones. Performance of mesoporous zeolites during both in-situ and ex-situ upgrading outweighed that of microporous zeolite, producing less solid and highly deoxygenated organic bio-oil rich in alkanes and monoaromatic hydrocarbons. The Upgraded bio-oil produced 38 wt% light fraction, 48 wt% middle distillate and 7.0wt% bottom product. This study demonstrated that bio-oil derived from Napier grass can be transformed to that high-grade bio-oil via catalytic upgrading over hierarchical mesoporous zeolite.
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Sanna, Aimaro. "Bio-oil generation and upgrading using catalysts towards its integration into a crude-oil refinery." Thesis, University of Nottingham, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556101.
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Currently biomass covers around 85% of the total renewable energy supply of the United Kingdom together with landfill gas and waste combustion. However its potential is still underutilized. Indeed, its conversion in fuels, energy and chemicals could revitalize rural economies, limit the dependence on foreign oil imports, and improve the environment by reducing fossil fuel consumption and thus reducing greenhouse gases. Recently, new pathways to convert the biomass into intermediate liquid namely bio-oil have been investigated. Pyrolysis is a promising technology to produce renewable fuels from biomass especially decentralized at point of production. However, the quality of bio-oil still remains a major limitation in terms of oxygen content and calorific value. The overall aim of this project was to contribute to the understanding of the engineering aspects in which biomass could be economically converted to chemicals, fuels and energy using catalytic pyrolysis to enhance the quality of the bio-oil. This can enable the production of intermediate bio-liquids with properties similar to those of petroleum, allowing the use of the existing crude-oil refinery settings for bio-oil upgrading into fuels. The integration of the bio-oil into a crude-oil refinery would sensibly decrease the economical disadvantage of biomass compared to fossil fuels. This work proposes an innovative three-step catalytic process that converts biorefinery residues, such as spent grains, into bio- oil by catalytic pyrolysis. The water insoluble fraction of the bio-oil (WIBO) is converted into a solid residue that possesses similar characteristics to those of coal, and a liquid product called bio-crude by a process name Thermo-t similar to the visbreaking process used to upgrade the quality of crude-oil heavy distillation residues. The water fraction (WSBO) is then converted into alcohols and alkanes using hydrogenation reactions. Despite the fact that the original biomass contains undesirable high oxygen (39-46 wt%) and moisture contents, there was a clear improvement in the properties of the bio-oils generated by catalytic pyrolysis that presented oxygen content of 26- 31 wt% and the final Thermo-t residue as the oxygen content was reduced by over 70% to 9-14 wt% on average. Catalytic pyrolysis was able to produce a bio-oil with less oxygen and nitrogen, high aliphatics and hydrogen using activated serpentine and olivine at low temperatures (370-430 QC). The activated materials seem to be beneficial to the bio-oil energy content that increase from less than 20 MJ/kg in the original biomass to 24-26 MJ/kg and finally to 29-37 MJ/kg after Thermo-t process. About 70-74% of starting energy remains in the bio-oil using ACOL and ACSE at 430 QC, respectively, while only 52% is retained using alumina at the same temperature. Finally, bio-crudes and bio-cokes from Thermo- t process retain 30 and 36% of the starting energy, respectively. The WSBO can be catalytically hydro-treated by Aqueous Phase Processing in a 1st stage at temperatures lower than 130 QC to reduce the organics removed as solid depositions to only 7 wt%, avoiding the typical catalyst deactivation of traditional hydro-treating technology. Then, in a 2nd stage at 220-250 QC, 93% of the partially deoxygenated bio-oil functionalities, such as ketones, aldehydes, aromatics and sugars are converted in much more stable functionalities that leave a final product with acidity and stability much compatible with current fossil fuels. Overall, this study has shown that there is a great technical scope for converting biomass into high-value products that can help to off-set fossil fuels.
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Bonnaillie, Laetitia Mary. "Bio-based polymeric foam from soybean oil and carbon dioxide." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 258 p, 2008. http://proquest.umi.com/pqdweb?did=1456290941&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Yu, Joyleene Ruth. "Bio-oil upgrading through biodiesel emulsification and catalytic vapour cracking." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46841.
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With our limited fuel supplies struggling to keep up with our ever-increasing demand for energy, and the rising trend towards sustainable and cleaner technologies, the need to harness the potential of bio-oil as an alternative source of energy has never been more compelling. Although crude bio-oil can already be utilized to supplement heating oils and boiler fuels, its greater value lies in its potential as a source of transportation fuels and chemicals after upgrading.
In collaboration with Diacarbon Energy Inc., the main objectives of this project were twofold: (1) investigating the effect of extraction location from their proprietary pyrolysis unit on crude bio-oil quality prior to its emulsification with biodiesel, and characterizing the resulting biodiesel- and lignin-rich layers; and (2) designing and building a catalytic test unit to perform in situ cracking of slow pyrolysis vapours.
Experimental results confirmed that extraction location does affect the crude bio-oil quality. The effect of the surfactant on the emulsification was minimal as the resulting biodiesel-rich layer from the emulsification without the surfactant showed similar improvements in terms of water content, viscosity, TAN and HHV. A water mass balance confirmed that the majority of the water (~97%) is retained in the lignin-rich phase after emulsification. This is significant because the solvency of biodiesel can be utilized to upgrade bio-oils by selectively extracting its desirable fuel components into a biodiesel-rich phase, which can then be easily separated from the lignin- rich phase where the higher molecular weight compounds, such as pyrolytic lignin, as well as the majority of the water, are retained.
The bio-oil samples obtained from the non-catalytic and catalytic vapour cracking experiments separated into two distinct layers – an aqueous and organic layer. While the aqueous layers were fairly similar in nature, the organic layer from the catalytic experiment showed a significant decrease in viscosity (94.3% less) and water content (64.3% less). The organic layer from the catalytic pyrolysis remained homogeneous while that from the non-catalytic pyrolysis split into a hazy aqueous layer (with suspended oil droplets) sandwiched between a thin organic layer on top and a thicker organic layer at the bottom.
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Adekunle, Kayode. "Bio-based Composites from Soybean Oil Thermosets and Natural Fibers." Doctoral thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-3587.
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In order to reduce over-dependency on fossil fuels and to create an environment that is free of non-degradable plastics, and most importantly to reduce greenhouse gas emission, bio-based products are being developed from renewable resources through intense research to substitute conventional petrochemical-based plastics with renewable alternatives and to replace synthetic fibers with natural fibers. Many authors have done quite a lot of work on synthesizing polymers from renewable origin. Polylactic acid (PLA) has been developed and characterized, and it was found that it has enormous potential and can serve as an alternative to conventional thermoplastics in many applications. Modification of the plant oil triglycerides has been discussed by many authors, and research is still going on in this area. The challenge is how to make these renewable polymers more competitive in the market, and if possible to make them 100% bio-based. There is also a major disadvantage to using a bio-based polymer from plant oils because of the high viscosity, which makes impregnation of fibers difficult. Although natural fibers are hydrophilic in nature, the problem of compatibility with the hydrophobic matrix must be solved; however, the viscosity of the bio-based resin from plant oils will complicate the situation even more. This is why many authors have reported blending of the renewable thermoset resin with styrene. In the process of solving one problem, i.e reducing the viscosity of the renewable thermoset resin by blending with reactive diluents such as styrene, another problem which we intended to solve at the initial stage is invariably being created by using a volatile organic solvent like styrene. The solution to this cycle of problems is to synthesize a thermoset resin from plant oils which will have lower viscosity, and at the same time have higher levels of functionality. This will increase the crosslinking density, and they can be cured at room temperature or relatively low temperature. In view of the above considerations, the work included in this thesis has provided a reasonable solution to the compounded problems highlighted above. Three types of bio-based thermoset resins were synthesized and characterized using NMR, DSC, TGA, and FT-IR, and their processability was studied. The three resins were subsequently reinforced with natural fibers (woven and non-woven), glass fibers, and Lyocell fiber and the resulting natural fiber composites were characterized by mechanical, dynamic mechanical, impact, and SEM analyses. These composites can be used extensively in the automotive industry, particularly for the interior components, and also in the construction and furniture industries. Methacrylated soybean oil (MSO), methacrylic anhydride-modified soybean oil (MMSO), and acetic anhydride-modified soybean oil (AMSO) were found to be suitable for manufacture of composites because of their lower viscosity. The MMSO and MSO resins were found to be promising materials because composites manufactured by using them as a matrix showed very good mechanical properties. The MMSO resin can completely wet a fiber without the addition of styrene. It has the highest number of methacrylates per triglyceride and high crosslink density.Akademisk avhandling för avläggande av teknologie doktorsexamen vid Chalmers Tekniska högskola försvaras vid offentlig disputation, den 6:e maj, Chalmers, KE-salen, Kemigården 4, Göteborg, kl. 10.00.
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Niroula, Varsha. "HYDROTHERMAL LIQUEFACTION OF SWEET SORGHUM BAGASSE FOR BIO-OIL PRODUCTION." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2301.
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Lignocellulosic feedstocks are the most abundant biomass on earth with a high potential of producing fuels and the shortage of fossil fuels and environmental pollution resulting from burning fossil fuels have boosted interest in lignocellulose in the past few decades. Hydrothermal Liquefaction (HTL) is a process where the biomass is heated at a high temperature and high pressure to produce bio-oil. Sweet sorghum bagasse has been used in our research for this process because of its abundance in the world and in the United States. HTL of sweet sorghum bagasse was carried out under varying conditions of temperature, catalyst concentration and reaction time. This study aimed to find out the optimum condition that can lead to maximum yield of bio-oil. By testing each variable at three levels, the Box Behnken design necessitated a total of 17 runs. Among these conditions, the highest bio-oil yield of 45.28% was observed at 300oC with K2CO3 at 1M and a residence time of 60 minutes. The obtained bio-oil yields under different operating conditions could be fitted well by a cubic model. This model predicted that a maximal bio-oil yield of 57% could be achieved if the HTL is conducted at 320oC with K2CO3 at 1M and a reaction time of 60 minutes. To confirm this model, HTL performed using the optimal condition led to a bio-oil yield of 52.215%. Under the same optimal condition, two more runs were carried out without the use of K2CO3 as a catalyst. The average bio-oil yield was 7.517%, which was much lower than those with the catalyst. Therefore, the presence of K2CO3 increased yield of bio-oil significantly. The CHNS/O analysis was conducted for selected bio-oil samples. The results indicated that bio-oil samples derived from HTL with K2CO3 had a high content of carbon and a very low content of sulfur and nitrogen. The oxygen content, however, was quite high. Thus, further upgrading the HTL bio-oil is needed to improve its heat content and fuel quality.
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Gerhauser, Heiko. "CFD applied to the fast pyrolysis of biomass in fluidised beds." Thesis, Aston University, 2003. http://publications.aston.ac.uk/9645/.
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Ágústsson, Arnar. "Fish oil in Icelandic road constructions. : A case study of bituminous binder mixtures modified with bio-oil." Thesis, KTH, Väg- och banteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149535.
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In this thesis an extensive background study on the use of bio-oil modified binder, used in surface dressings in Iceland, was carried out. Surface dressings, or chip seals, are paved by first spraying out binder and then distributing aggregates over the surface before compaction. The bio-oil, most notably fish oil ethyl ester or rape seed oil, is included in a binder mixture to lower its viscosity, enabling the binder to be sprayed out at a lower temperature than unmodified bitumen. In January 2013, severe bleeding of binder was noticed on road sections paved with bio-oil modified surface dressings in the northern part of Iceland. Following the bleeding, the Icelandic Road and Coastal Administration (IRCA) sent samples of the sections in question, as well as binder samples, for testing at the laboratory of Highway and Railway Engineering at KTH Royal Institute of Technology (KTH) in Stockholm, Sweden. The conclusions of that study were that the fish oil ethyl ester was highly polar and had solubility issues with the bitumen. This was found to have led to the fish oil separating from the binder mixture and covering the stones, preventing bonding between aggregates and binder [1]. The laboratory tests in this thesis extend on the aforementioned research. Through the background investigation it was found thatWetfix N, an adhesion promoter, was used in the binder mixture to facilitate bonding to the aggregates. Based on these findings, previous work and field experience in Iceland, two sample sets were created. The first sample set included 7.5% of either fish oil ethyl ester or rape seed oil by weight, while the second set included 4% of the same bio-oils by weight. To determine the effect of the adhesion promoter, all samples were tested with and without Wetfix N. Furthermore, all samples were put through a short-term aging treatment to simulate the process during mixing and paving, and tested again. The findings of this study suggest that the fish oil ethyl ester is more suitable for road constructions, compared to the rape seed oil, and that adhesion promoter should always be included when paving surface dressings in Iceland. Furthermore, the samples tested cannot be recommended for field use due to high polarity in the sample with a fish oil concentration of 7.5% and too high viscosity in the sample which includes 4% of fish oil. Therefore, it can be said that the upper and lower limits have been narrowed to the range between the two concentrations tested. To better understand the properties and behavior of the sample mixtures, a complete adhesion test with aggregates is advisable. Viscosity testing of samples which include between 4.5% and 7% of fish oil by weight are recommended and the mixture with the lowest concentration that passes IRCA’s guidelines for spraying viscosity at a desired temperature should be used in practice.
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Sekar, Ananda Kumaran. "EFFECT OF SUPERCRITICAL WATER TREATMENT ON THE COMPOSITION OF BIO-OIL." MSSTATE, 2008. http://sun.library.msstate.edu/ETD-db/theses/available/etd-08052008-124234/.
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The effect of supercritical water treatment on the composition of bio-oil was investigated. Preliminary studies were carried in batch mode using a bio-oil simulant. This bio-oil simulant was designed to mimic crude bio-oil by possessing the same functional groups as are found in crude bio-oil, but with reduced complexity. Experiments of this type allow to be gained of the reaction chemistry involved. These were then followed up by experiments using crude bio-oil. Critical process parameters for all these experiments were reaction time, bio-oil/water ratio, reaction temperature and pressure. One of the objectives of this work was to identify processing conditions that would either suppress formation of, or elimination of the coke precursors. This would then result in a bio-oil with improved storage characteristics and a reduced tendency towards coke formation during catalytic upgrading. The results suggest that supercritical water treatment can effectively eliminate the coke pre-cursors resulting from bio-oil, resulting in a bio-oil with improved properties.
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Omais, Badaoui. "Oxigen speciation in coal-derived liquids and bio-oil upgrading products." Paris 6, 2012. http://www.theses.fr/2012PA066262.
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In order to alleviate the transport sector’s reliance on oil, diversifying the liquid fuel supplies for the transportation field is of the upmost importance and recently, coal-derived liquids and upgraded bio-oils have sparked great interest as the new generation substitutes. However, these liquids have high oxygen contents and characterizing oxygenated compounds is crucial to monitor reaction mechanisms and optimize conversion conditions. Therefore, the objective of the Ph. D. Was to develop powerful analytical systems to characterize oxygenated compound in coal and biomass oils. For this purpose comprehensive two-dimensional gas chromatography (GCxGC) was investigated and led to a breakthrough characterization of alcohols and phenols. Three other analytical tools were considered to unravel coal-derived liquids composition: High resolution mass spectrometry (FT-ICR/MS), 31P NMR and UV-visible spectroscopy. 70%w/w and 86%w/w of the oxygen content respectively in the naphtha and the gasoil cuts were identified and quantified. GC×GC optimization for oxygen speciation in upgraded bio-oils enabled the quantification of 60%w/w of the sample. As this technique does not offer enough resolution, a third dimension of separation involving supercritical fluid chromatography was integrated online prior GC×GC analysis (SFC-GCxGC). This system led to a detailed quantification of phenols, benzenediols, naphthols, and methoxyphenols in these matrices. Through these two products, theoretical considerations on orthogonality and on separation mechanisms governing GCxGC were deduced and presented in a third sectionDans l'optique de leur valorisation en carburants alternatifs, il s'avère important d'acquérir une connaissance plus étendue des liquéfiats de charbon et des huiles de biomasse, notamment d'élucider la composition chimique des oxygénés présents en relativement forte concentration. L'objectif de cette thèse est donc de développer des systèmes analytiques résolutifs permettant de séparer les molécules oxygénées présentes dans ces produits. L'analyse des liquéfiats de charbon (0,5-5%m/m O) a été permise par la chromatographie en phase gazeuse bidimensionnelle et a mené à une quantification inédite des alcools et des phénols. Les autres familles chimiques oxygénées ont été quantifiées par une approche analytique multi-technique faisant appel à la spectrométrie de masse très haute résolution (FT-ICR/MS), à la spectroscopie RMN et à la spectroscopie UV-visible. Au total, 70%m/m et 86%m/m de l'oxygène élémentaire a été quantifié. L'optimisation des conditions en GC×GC a aussi permis de quantifier 60%m/m de l'oxygène élémentaire présent dans les bio-huiles upgradées (10-20%m/m O), mais cette technique reste tout de même limitée en termes de résolution face à la complexité de ces huiles. Une troisième dimension de séparation par chromatographie en fluide supercritique a été couplée en ligne, en amont de l'analyse par GCxGC (SFC-GCxGC). Ce système permet une analyse quantitative détaillée des phénols, benzènediols, guaiacols et naphthols dans ce type de matrice. A travers l'analyse de ces deux produits, des considérations théoriques sur les notions d'orthogonalité et sur les mécanismes de rétention régissant les séparations ont été déduites
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Abu, Bakar Muhammad. "Catalytic intermediate pyrolysis of Brunei rice husk for bio-oil production." Thesis, Aston University, 2013. http://publications.aston.ac.uk/20899/.
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Rice husks from Brunei were subjected via intermediate pyrolysis for bio-oil production. Two main objectives were set out for this study. The application of intermediate pyrolysis on Brunei rice husk for the production of bio-oil is the main objective of this experiment. Characterisation of the rice husks was inclusive as a pre-requisite step to assess the suitability as feedstock for production of liquid fuels. Following on from the characterisation results, a temperature of 450°C was established as the optimum temperature for the production of bio-oil. A homogenous bio-oil was obtained from the pyrolysis of dry rice husk, and the physicochemical properties and chemical compositions were analysed. The second objective is the introduction of catalysts into the pyrolysis process which aims to improve the bio-oil quality, and maximise the desired liquid bio-oil properties. The incorporation of the catalysts was done via a fixed tube reactor into the pyrolysis system. Ceramic monoliths were used as the catalyst support, with montmorillonite clay as a binder to attach the catalysts onto the catalyst support. ZSM-5, Al-MCM-41, Al-MSU-F and Brunei rice husk ash (BRHA) together with its combination were adopted as catalysts. Proposed criterions dictated the selection of the best catalysts, subsequently leading to the optimisation process for bio-oil production. ZSM-5/Al-MCM-41 proved the most desirable catalyst, which increases the production of aromatics and phenols, decreased the organic acids and improved the physicochemical properties such as the pH, viscosity, density and H:C molar ratios. Variation in the ratio and positioning of both catalysts were the significant key factor for the catalyst optimisation study.
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Tao, Yongwen. "Catalytic transformation of crude bio-oil to valuable chemicals and fuels." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15906.
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Hydrogen has been regarded as the most environmental friendly energy carrier due to its easily-storage and high energy concentration. A variety of technologies have been studied to generate hydrogen. Ethanol steam reforming is one of the most promising ways to generate hydrogen since its high productivity. However, the high operating temperature is the main challenge for developing the process. Metallic catalysts have been widely investigated to improve the performance of ethanol steam reforming process. Ni-based catalysts are frequently studied due to their good catalytic performance and low cost for ESR. However, quick deactivation is still a major challenge for Ni-based catalysts, which is mainly caused by coke formation or metal sintering. In this thesis, improvements of Ni-based catalysts have been studied in two approaches: introducing a second metal of Cu to form bimetallic catalysts and Optimizing Ni content in catalysts that Ni is supported on CaO modified Al2O3. Bimetallic CuNi/YSZ catalysts were synthesized by impregnation. Results showed that adding Cu to Ni-based catalysts successfully improved the catalytic stability while Cu has barely activity in ESR. The formation of Cu-Ni alloy can improve catalyst reducibility and stabilize Ni from sintering. Ni supported on CaO modified Al2O3 catalysts were synthesized by co-precipitation. Introducing of CaO to Al2O3 support successfully improved the stability of catalysts by reducing acidity sites since the acidic property of Al2O3 leads to serious coke formation in ESR. Different Ni loading ratios contribute to the formation of different Ni-containing compounds, which have various catalytic performances in ESR. Increasing Ni loading ratio has positive effect on catalytic activity. But excess Ni loading does influence the particle size, metal dispersion and reducibility.
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Kim, Kyungduk. "Novel Nanocatalyst for the Selective Hydrogenation of Bio-Oil Model Compounds." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16353.
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This thesis focuses on the understanding the effect of various factors, such as physical structures of metal particles, chemical composition of supports and metal-support interactions, on the catalytic performance of Pd or Pt nanocatalysts for hydrodeoxygenation (HDO) of bio-oil model compounds. The first part of the thesis addressed the alternative catalyst synthesis strategy based on emerging double-flame spray pyrolysis method (FSP), which was able to tune the catalytic properties of nanocatalysts without changing their precursors and chemical compositions during the synthesis. A series of Pd catalysts on the silica-alumina supports, SiO2- , and Al2O3 supports have been synthesized with the tunable surface properties within micro-seconds. The characterization results showed that various flow rates of precursors and gases used for the synthesis of catalysts influenced the formation of the catalyst structures and further change the surface acidity of catalysts due to the correlation between acidity and structure, but, the flow rates did not influence the electronic properties of Pd particles. Therefore, the higher conversion but the similar chemoselectivity have been reached in the hydrogenation of the bio-oil model ketone compound-acetophenone The second part is to identify the dominant effects from size of metal catalysts (under uniform shape and face) or the support acidity in the hydrodeoxygenation of the bio-oil model compounds of acetophenone, benzaldehyde, and butyrophenone. The uniform cubic Pd particles with different size (8, 13, and 21 nm) have been synthesized and loaded on the most popular supports (SiO2-, Al2O3-, and silica-alumina) with various functional groups and acidity. The results showed different acidities on the supports (Brønsted acidic site for Silica-alumina, Lewis acidic site for Al2O3-, and non/weak silanol OH group for SiO2- support) could not influence the chemoselectivity of the reaction but effected the conversion obviously. The particle size has more significant influence than the acidity. The smallest (8nm) Pd particle catalysts regardless of kinds of supports revealed the highest conversion for the hydrogenation the bio-oil model compounds. The third part focused on the influence of various types of catalysts with different acidities, chemical composition, and metal-support interaction on enantioselective hydrogenation of several model compounds in two reaction systems: 1). Pt-cinchrona modified system, and 2). Pd-(S) proline modified system. The result indicated acidic supports promoted the both conversion and enantioselectivity. Specially, Pd/SA made by double-FSP method, which has the highest Brønsted acid sites, showed 100 % conversion of isopherone on 60 min with 99% ee values.
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Chen, Mengmeng. "Hydrodeoxygenation of bio-oil model compounds on supported noble metal catalysts." Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/9398.
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This thesis focuses on understanding acidic effects on the mechanisms of Pt or Pd-catalyzed bio-oil model ketone or aldehyde hydrodeoxygenation (HDO) and application of nanocatalysts - supported Pt and Pd with different surface acidity in the hydrodeoxygenation of acetophenone and benzaldehyde. The first part of the thesis addressed the understanding of bio-oil model ketone compound - acetophenone hydrodeoxygenation mechanism over alumina and silica-alumina supported Pt and Pd catalysts by in-situ attenuated total reflection infrared spectroscopy (ATR-IR) in combination with modulation excitation spectroscopy (MES) and phase sensitive detection (PSD). Experimental results indicated acidic supports promoted the hydrodeoxygenation of acetophenone (AP) to produce ethylbenzene (EB). Specially, on alumina supported Pt, AP was predominantly adsorbed on Pt via its η1 (O) configuration and this species was hydrogenated with high chemoselectivity to 1-phenylethanol (PE). On silica-alumina supported Pd, hydrodeoxygenation of AP to EB involves transformation of a carbonyl group to PE via η1 (O) configuration, followed by a dehydration producing styrene on acidic sites of supports, the styrene was further hydrogenated to EB on Pd. The second part focused on the application of acidic supports supported catalysts Pt/Al-MCM-41 and Pt/SiO2-Al2O3 on hydrodeoxygenation of acetophenone and benzaldehyde. Results indicated that Pt/Al-MCM-41 catalysts serve as bifunctional catalysts in the hydrogenation of AP. The overall activity over the noble metal catalysts on acidic supports MCM-41 increased with the increase of surface acidity up to support Si/Al=20, further increase the surface acidity leads to the decrease of catalytic activity. The increase of surface acidity up to Si/Al=20 also promotes the hydrogenation of aromatic ring to produce CMK and CE. For hydrodeoxygenation of benzaldehyde, products toward hydrogenation of both carbonyl and aromatic ring can be produced on a reference Pt/Al2O3 catalyst at 80°C whereas when temperature was increased to 200°C, only toluene and benzene can be detected. SiO2-doped Pt/SiO2-Al2O3 catalysts showed 10%-20% higher catalytic activity than reference catalyst of Pt/Al2O3 under similar reaction condition. Acidity did also influence catalytic selectivity of benzaldehyde hydrodeoxygenation, toluene prefers to form on relative low acidic catalysts whereas methylcyclohexane was more easily formed on high acidic catalysts.
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Razzaque, Md Abdur. "Development and assessment of a fast pyrolysis reactor for bio-oil, syngas and bio-char production from biomass residues." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32706/.
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Design, development and assessment of a Fluidized Bed Reactor (FBR) is a very complex process, where enormous empirical correlations; charts and graphs; lot of parameters, assumptions, unit operations are involved, straight forward design equations and design data are limited, and generally the operation of the system requires many adjustments. The improved design of FBR with high coefficient of performance (COP), low energy consumption, high yield and environmentally friendly (low emission) is the target. The scope of the study is to design and fabrication of a lab scale fluidized bed fast pyrolysis system with throughput capacity of 1 kg of dry biomass per hour which includes a bubbling fluidized bed reactor, 2 cyclone separators in series, 4 condensers in series operating between temperatures of 600-300; 300-200; 200-125 and 125-40˚C to selectively condense alkanes, phenols, aromatics, indene, methyl-indene, benzene, toluene, methyl–naphthalene, esters, acids, alcohols, ketones; 2 heaters (1 pre- and 1 primary), an auger feeder with hopper and controller, blowers and rig structure. A 3-D simulation was performed to facilitate the mounting of different unit operations, instruments and control panels with sufficient maintenance and manoeuvring accessibilities yet compact structure with low structural footprints. The rig is having the dimensions of 2204X2750X1100mm (L x H x W) and suitable for batch operation to produce about 650 gm bio-oil, 150 gm non-condensable and 200 gm bio-char from 1kg of dry biomass pyrolysis. The rig is manually operated, however the data acquisition and logging systems are digital and has provision of scrubbing exhaust gas, and an online analyser has been installed to measure and monitor lower hydrocarbons including hydrogen concentrations and Lower Explosive Limit (LEL) in the exhaust gas. Four types of biomass such as Empty fruit bunch (EFB), Urban tree shavings (UTS), Saw dust Broga (SDB) and Saw dust Semenyih (SDS) were pre-treated with aqueous acidic (H2SO4) and alkaline (NaOH) solutions to find the percentage of solids extraction with varying liquid-solid ratios, acid/alkali concentrations, reaction temperatures and retention time. For pyrolysis operation, UTS was selected among the four biomass samples with a set of pre-treatment parameters (4.81 wt. % H2SO4, 15:1 liquid-solid ratio, 4hr retention time, 70˚C, 100rpm agitation speed) that maximizes bio-oil production. Pyrolysis in a batch tubular furnace at 600˚C with nitrogen flowrate of 30 ml/min resulted in bio-oil yield of 39.43% and 27.67%, and char yield of 38.07% and 30.73% from raw and pre-treated UTS respectively. The semi-batch pyrolysis results were compared with biomass pyrolysis results from the batch pyrolysis rig operations. The catalytic upgrading of the bio-oil to liquid fuel in a batch reactor is ongoing research work. The contribution of this research can be summarised as the successful design, fabrication, testing and operation of a Fluidized Bed System to produce fuel from biomass in batch pyrolysis. Characterization of the feedstock to get the optimum operation condition of the designed FBR to get the best yield out of the system and evaluation of the performance characteristics (Mass and Energy Balance) of the system. Characterization of the products (bio-oil, bio-char and syngas) following standard methods having results comparable with literature.
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Jahangiri, Hessam. "Clean catalytic technologies for upgrading bio-oil to produce fuels and chemicals." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/11809.
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The upgrading of bio-fuels derived from the fast pyrolysis of biomass is currently a topic of great interest due to the increasing concerns over the use of fossil fuels and the drive towards renewable feedstock. The ketonisation reaction is one method for reducing the oxygen content and acidity of derived bio-fuel. The ketonisation reaction converts carboxylic acid molecules into ketone, water and carbon dioxide. In this thesis a range of metal oxide catalysts and zeolite catalysts have been investigated for bio-oil upgrading via the ketonisation reaction and catalytic fast pyrolysis. The prepared catalysts were characterised by XRD, N2 porosimetry, XPS, pyridine DRIFTS, Raman spectroscopy, ammonia titration TPD, propylamine chemisorption TPD and CO2 titration TPD experiments. The three phases of bulk zirconia (amorphous, tetragonal and monoclinic) have been utilised in the ketonisation of acetic acid in a continuous flow reactor in this study. A series of mesoporous silica-supported zirconia catalysts (ZrO2/SBA-15) were also evaluated to investigate the effects of surface area and porosity. In addition, catalyst deactivation has been investigated on zirconia and ZrO2/SBA-15 series in ketonisation reaction. The influence of different loadings of gallium (0.2 wt.% - 11wt.%) doped ZSM-5 and Zeolite Beta and also bulk Ga2O3 was explored in the ketonisation of acetic acid in a continuous flow reactor at three reaction temperatures 350 o C, 400 o C and 450 o C. Finally, non-catalytic pyrolysis GC/MS is performed to identify the cellulose compound groups. Hence, catalytic pyrolysis GC/MS was used to evaluate the effect of gallium loadings (0.2 wt.% - 11wt.%) on ZSM-5 and Zeolite Beta in the cellulose pyrolysis reaction.
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Matayeva, Aisha <1990>. "Development of innovative processes and catalysts for the valorisation of Bio-Oil." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amsdottorato.unibo.it/8785/1/thesis_final_Bologna-resubmission%20Matayeva.pdf.
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Hydrothermal liquefaction (HTL) is a process for converting waste biomass to bio-oil by contacting the biomass with water at high temperatures and sufficient pressures in order to keep the water in the liquid state. HTL process is energy efficient and capable of dealing with wet biomass, such as sorted domestic organic waste, sewage sludge, algae, etc.
However, HTL oils contain high contents of oxygen and nitrogen because of the initial biomass composition. Therefore, the bio-oil has to be upgraded in order to produce advanced transport fuels. Information regarding the nitrogen compounds present in bio-oil is of major concern of any hydrotreatment, since the low hydrodenitrogenation rate and catalyst poisoning by nitrogen compounds make this process expensive.
Therefore, the main goal of the present study is the investigation of the HTL reaction mechanism, focusing the attention on the nitrogen containing species pathways, with the goal to increase the energy yields and reduce the nitrogen content in the produced bio-oil.
Due to the complexity of the biomass composition, model compounds that encompass all the biochemical components of biomass, namely proteins, lipid and carbohydrates, are emerged to unravel the main chemical reaction pathways existing between macromolecular components. Moreover, several microbial biomass types, such as oleaginous yeast and liamocins, were also treated via HTL.
The whole study helps to better understand the HTL of organic waste biomass and microbial biomass/oils, providing useful insights into the reaction products, pathways, and mechanisms for the production of bio-oils and chemicals.
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Pietrzyk, Julian Darius. "Use of microbial consortia for conversion of biomass pyrolysis liquids into value-added products." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31562.
Full textAbstract:
Lignocellulosic biomasses are considered promising feedstocks for the next generation of biofuels and chemicals; however, the recalcitrance of lignocellulose remains a barrier to its utilisation over conventional sources. Pyrolysis is the heating of biomass to several hundred degrees Celsius in the absence of oxygen, which can thermally depolymerise lignocellulose. Products of pyrolysis are a solid biochar, liquid bio-oil and syngas. Biochar has roles in both carbon sequestration and soil amendment however bio-oil has no defined use, despite a high concentration of fermentable sugars. Bio-oil is a complex organic microemulsion with a host of biocatalyst inhibitors that makes its microbial degradation a challenge. In this work, the use of aerobic cultures using microbial communities isolated from natural environments saw limited potential; however, the use of anaerobic digestion (AD) successfully generated a higher volume of biogas from reactors with bio-oil than controls. Biogas yield test reactors were set up with anaerobic digestate from a wastewater treatment plant as the substrate for degradation and conversion of bio-oils. Next-generation 16S rRNA gene sequencing was utilised to characterise the communities in the reactors while the ultrahigh resolution mass spectrometry technique of Fourier transform ion cyclotron resonance (FT-ICR) was used for characterisation of the chemical changes occurring during AD. Both sets of high-resolution data were additionally combined for multivariate analysis and modelling of the microbial genera that correlated best with the changes in digestate chemistry. This represents a novel analysis method for the microbial degradation of complex organic products. Bio-oil from common lignocellulosic feedstock was the most easily degradable by the AD communities, with significant inhibition observed when bio-oils from anaerobic digestate and macroalgae were used. Additionally it was found that the inclusion of biochars that were pre-incubated in anaerobic digestate prior to use in AD were capable of significantly reducing the lag time observed for biogas production in bio-oil-supplemented reactors. The addition of biochars that were not pre-incubated had no effect on biogas production. Specific inhibition of methanogenesis was also capable of causing the digestates to accumulate volatile fatty acids (VFAs) as a product of greater value than biogas. Scale-up experiments will be required to confirm the precise practicalities of the addition of bio-oil to AD as well as to establish the potential for isolation and purification of VFAs.
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Alves, Margot. "Carbon dioxide and vegetable oil for the synthesis of bio-based polymer precursors." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0129/document.
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Bien que thermodynamiquement et cinétiquement stable, le dioxyde de carbone est une molécule qui peut être convertie en carbonates cycliques à cinq ou six atomes respectivement au départ d’époxydes ou d’oxétanes moyennant l’utilisation d’un catalyseur approprié. Ces carbonates cycliques sont utilisés comme solvants verts, électrolytes pour les batteries au lithium ou comme intermédiaires pour la synthèse de polymères. Cependant, les performances catalytiques doivent être améliorées en particulier pour lecouplage du CO2 avec les huiles végétales époxydées ou les oxétanes. Dans ce contexte, nous avons développé un nouveau catalyseur homogène bicomposant organique composé d’un sel d’ammonium jouant le rôle de catalyseur et d’un co-catalyseur fluoré simple ou double donneur de liaison hydrogène. Dans un premier temps, l’efficacité de ces nouveaux catalyseurs a été évaluée et optimisée pour le couplage entre un époxyde terminal et le CO2 via des études cinétiques par spectroscopie FTIR ou Raman in-situ sous pression. Ces études ont démontré que l’utilisation combinée de sels d’ammonium et d’alcools fluorés induit un effet synergique permettant la fixation rapide et sélective du CO2 sur les époxydes modèles et les huiles végétales époxydées dans des conditions douces et sans solvant. L’utilisation de cette plateforme catalytique performante a ensuite été exploitée pour la synthèse d’oligocarbonates hydroxyles téléchéliques au départ d’oxétanes nettement moins réactifs que les époxydes. Ces oligocarbonates ont finalement été valorisés pour la synthèse de polyuréthanes CO2-sourcés par extension de chaines en présence de diisocyanates. En complément de ces travaux, une compréhension fine des mécanismes réactionnels a été réalisée via calculs DFT qui ont mis en évidence que l’efficacité catalytique de ces catalyseurs était liée à la stabilisation multiple des intermédiaires et états de transition par liaisons hydrogènes. A ce jour, via une étude comparative, nous avons mis en évidence que ce système catalytique bicomposant constitue un des catalyseurs organiques les plus performants pour le couplage du CO2 et d’époxydes et le seul système organique permettant la conversion d’oxétanes en synthons d’intérêtAlthough it is a thermodynamically and kinetically stable molecule, carbon dioxide can beconverted into five- and six-membered cyclic carbonates by coupling with epoxides or oxetanes, respectively, using appropriate catalysts. Cyclic carbonates are used as green solvents, electrolytes for Liion batteries or intermediates for the synthesis of polymers. However, the catalytic performance must be further enhanced in particular for the coupling of CO2 with epoxidized vegetable oils or oxetanes. In this context, we developed a new highly efficient bicomponent homogeneous organocatalyst composed of anammonium salt as the catalyst and fluorinated single or double hydrogen bond donors as co-catalysts. First,a screening of onium-based catalysts and hydrogen-bond donors was performed. Performances of thecatalysts and optimization of the reaction was realized through detailed kinetics studies using in-situ FTIR/Raman spectroscopy under pressure. We demonstrated that fluorinated alcohols showed unexpected co-catalytic activity due to synergisms between the onium salt and fluorinated co-catalysts enabling the fast and selective addition of CO2 on to model epoxides and epoxidized vegetable oils under solvent-free and mild experimental conditions. The use of this powerful dual catalyst was then extended to the first organocatalytic coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonates that were used asprecursor of CO2-based polyurethanes by chain-extension with a diisocyanate. In addition, a fine comprehension of the mechanisms was investigated by DFT calculations highlighting that the co-catalytic performance of the onium salt/fluorinated alcohol binary catalyst arose from the strong stabilization of the intermediates and transitions states by hydrogen-bonding. To date, through comparative studies, we evidenced that this new catalyst is one
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Menon, Akshay. "Partial hydrodeoxygenation of a heavy bio-based oil fraction : (A technical feasibility study)." Thesis, KTH, Kemiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-288988.
Full textAbstract:
This report is intended to provide the reader with an extensive background information on hydrode oxygenation (HDO) of Tall Oil Pitch (TOP), combined with results from chemical property analyses of the same. Firstly, the importance of hydrogenation and oxygen removal for a biomass-based feed material is highlighted. The chemical nature of TOP in general is described and the target for the research work is identified. It is decided to evaluate the possibility of TOP as a prospective material for achieving partial oxygen removal. The effect of catalysis on HDO behavior is assessed, and subsequently, conventional commercial catalysts are selected. Chemical analyses of the feed mixture provided data on various properties, which can then be correlated to the products from hydrogenation. Kinematic viscosity of TOP is determined, followed by acid number and saponification number tests to evaluate the free acid and total acid contents respectively. Reasoning for any deviations are highlighted and suggestions are provided to control deviation in process parameters. GC/MS analysisof the tall oil sample is also conducted to understand the presence of oxygen-containing species. Carbon residue and ash tests revealed the coking and ash forming tendency of the samples. In addition, XRF spectroscopy results indicated the metal presence in the TOP sample. Experimental trials are carried out to sulphide the catalysts prior to use in hydrogenation experiments. Catalyst sulphidation procedure is also outlined. Furthermore, the lab-scale reactor is tested for hydrogenation to determine challenges that normally arise during high-pressure working conditions. In addition to discussion of challenges regarding batch hydrogenations and sulfidations, proposals on future work in this domain is outlined, along with suggestions on an experimental pathway forward.
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Greenhalf, Charles. "Thermochemical characterisation of various biomass feedstock and bio-oil generated by fast pyrolysis." Thesis, Aston University, 2014. http://publications.aston.ac.uk/20906/.
Full textAbstract:
The projected decline in fossil fuel availability, environmental concerns, and security of supply attract increased interest in renewable energy derived from biomass. Fast pyrolysis is a possible thermochemical conversion route for the production of bio-oil, with promising advantages. The purpose of the experiments reported in this thesis was to extend our understanding of the fast pyrolysis process for straw, perennial grasses and hardwoods, and the implications of selective pyrolysis, crop harvest and storage on the thermal decomposition products. To this end, characterisation and laboratory-scale fast pyrolysis were conducted on the available feedstocks, and their products were compared. The variation in light and medium volatile decomposition products was investigated at different pyrolysis temperatures and heating rates, and a comparison of fast and slow pyrolysis products was conducted. Feedstocks from different harvests, storage durations and locations were characterised and compared in terms of their fuel and chemical properties. A range of analytical (e.g. Py-GC-MS and TGA) and processing equipment (0.3 kg/h and 1.0 kg/h fast pyrolysis reactors and 0.15 kg slow pyrolysis reactor) was used. Findings show that the high bio-oil and char heating value, and low water content of willow short rotation coppice (SRC) make this crop attractive for fast pyrolysis processing compared to the other investigated feedstocks in this project. From the analytical sequential investigation of willow SRC, it was found that the volatile product distribution can be tailored to achieve a better final product, by a variation of the heating rate and temperature. Time of harvest was most influential on the fuel properties of miscanthus; overall the late harvest produced the best fuel properties (high HHV, low moisture content, high volatile content, low ash content), and storage of the feedstock reduced the moisture and acid content.
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Kalgo, Abba Sani. "The development and optimisation of a fast pyrolysis process for bio-oil production." Thesis, Aston University, 2011. http://publications.aston.ac.uk/15808/.
Full textAbstract:
A two-tier study is presented in this thesis. The first involves the commissioning of an extant but at the time, unproven bubbling fluidised bed fast pyrolysis unit. The unit was designed for an intended nominal throughput of 300 g/h of biomass. The unit came complete with solids separation, pyrolysis vapour quenching and oil collection systems. Modifications were carried out on various sections of the system including the reactor heating, quenching and liquid collection systems. The modifications allowed for fast pyrolysis experiments to be carried out at the appropriate temperatures. Bio-oil was generated using conventional biomass feedstocks including Willow, beechwood, Pine and Miscanthus. Results from this phase of the research showed however, that although the rig was capable of processing biomass to bio-oil, it was characterised by low mass balance closures and recurrent operational problems. The problems included blockages, poor reactor hydrodynamics and reduced organic liquid yields. The less than optimal performance of individual sections, particularly the feed and reactor systems of the rig, culminated in a poor overall performance of the system. The second phase of this research involved the redesign of two key components of the unit. An alternative feeding system was commissioned for the unit. The feed system included an off the shelf gravimetric system for accurate metering and efficient delivery of biomass. Similarly, a new bubbling fluidised bed reactor with an intended nominal throughput of 500g/h of biomass was designed and constructed. The design leveraged on experience from the initial commissioning phase with proven kinetic and hydrodynamic studies. These units were commissioned as part of the optimisation phase of the study. Also as part of this study, two varieties each, of previously unreported feedstocks namely Jatropha curcas and Moringa olifiera oil seed press cakes were characterised to determine their suitability as feedstocks for liquid fuel production via fast pyrolysis. Consequently, the feedstocks were used for the production of pyrolysis liquids. The quality of the pyrolysis liquids from the feedstocks were then investigated via a number of analytical techniques. The oils from the press cakes showed high levels of stability and reduced pH values. The improvements to the design of the fast pyrolysis unit led to higher mass balance closures and increased organic liquid yields. The maximum liquid yield obtained from the press cakes was from African Jatropha press cake at 66 wt% on a dry basis.
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Saithai, Pimchanok. "Synthesis and characterization of bio-based copolymers from soybean oil and methyl methacrylate." Thesis, Montpellier, SupAgro, 2013. http://www.theses.fr/2013NSAM0008.
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L'objectif de ce travail était d'étudier l'impact du mode de préparation et de la formulation de bioplastiques transparents issus d'huile de soja sur leur structure et leurs propriétés thermiques et mécaniques. Nous nous sommes plus particulièrement intéressés à l'huile de soja époxydée (ESO), qui a ensuite été acrylée et co-polymérisée avec méthacrylate de méthyle (MMA) en présence ou non de nano-particules de dioxyde de titane. Deux méthodes de préparation d'ESO ont été comparées. La première a fait appel à une époxydation chimique en présence de peroxyde d'hydrogène et d'acide formique. L'acide sulfurique a été utilisé comme catalyseur pour la production de peracides, ces oxydants forts générant ensuite des époxydes par attaque des doubles liaisons des acides gras de l'huile. La seconde consistait en une époxydation chimio-enzymatique, les peracides étant alors générés dans des conditions douces de pH et de température par catalyse enzymatique en présence d'H2O2 et d'huile. Deux types de lipases ont été utilisées comme biocatalyseurs : la lipase de Candida antarctica (Novozyme 435) et la lipase/acyltransférase de C. parapsilosis. Un contrôle de la réaction a permis d'obtenir des produits à différents degrés d'époxydation (50 et 75 3 %). Les effets du mode d'époxydation, du degré d'acrylation et des teneurs en MMA et TiO2 sur les propriétés des bioplastiques obtenus ont été étudiés par FTIR, RMN 1D et 2D, DMTA, TGA et par mesure des propriétés mécaniques.Mots-clés : Biocomposite, Bioplatique, Nanocomposite, Huile de soja époxydée et acrylée (AESO), Dioxyde de titane (TiO2), Biocatalyse, LipaseThe aim of this research to study the effect the production method and the formulation of transparent soybean oil-based bioplastics on their structure and their thermal and mechanical properties. We focused on epoxidized soybean oil (ESO), that was acrylated and copolymerized methyl methacrylate (MMA) with and without titanium dioxide (TiO2). Two methods of ESO preparation were compared. The first used chemical epoxidation in the presence of H2O2 and formic acid, using sulfuric acid as a catalyst to produce peracids as strong oxydants for the epoxidation. The second one was a chemo-enzymatic method where the peracids were generated in mild conditions by an enzyme in the presence of H2O2. Two types of lipases were selected as biocatalysts for the chemo-enzymatic epoxidation: Novozyme®435 and a non-commercial lipase/acyltransferase (CpLIP2). The reaction was controlled so as to obtain different degrees of epoxidation (DOE), i.e. 50+/-3 mol% and 75+/-3 mol%, from both methods. Acrylated ESO (AESO) was chemically synthesized by acrylation of ESO and acrylic acid. Then AESO was copolymerized with MMA and cured to form a rigid polymer using 1 wt% of benzoyl peroxide as a free radical initiator. A nanocomposite was prepared by blending AESO-co-PMMA with 0.1-0.2 wt% nano-TiO2 (particle size 2-5 nm). The effect of degree of acrylation, MMA content and titanium dioxide content on structural, tensile and thermal properties of the obtained bioplastics were studied using Fourier transform infrared spectrometer (FTIR), 1D and 2D NMR, dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA) and mechanical properties determination
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Wang, Meng. "Steam reforming of model compounds of bio-oil with and without CO₂ sorbent." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/212.
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Hydrogen as a clean energy carrier has drawn great attention. Production of H2 from sustainable bio-oil is considered an alternative for conventional fossil fuel based energy system, since the overall process of bio-oil converting to H2 ideally is carbon-neutral and hence environmental friendly. This study focuses on developing an adequate catalyst for bio-oil steam reforming to produce H2. Ruthenium and/ or nickel based catalysts supported on alumina, ceria-alumina or ceria-silica were synthesized by sol-gel method or incipient wetness impregnation and characterized using BET Surface area analysis, Powder X-Ray diffraction (XRD), Temperature Programmed Reduction (TPR) and Scanning Electron Microscopy (SEM). Steam reforming of selected model compounds, n-propanol, glycerol and acetic acid, was investigated in a fixed bed tubular flow reactor over the prepared catalysts at 450 or 500 °C. The effects of support nature, preparation method, catalyst composition and reaction temperature on the steam reforming activity and stability of catalysts were studied. Catalysts showing better performance in terms of reactant conversion and H2 yield were selected for investigating the steam reforming of an acetic acid/glycerol aqueous mixture, consisting of acetic acid and glycerol with a weight ratio of 3/7 similar to a bio-oil generated from fast pyrolysis of cellulose. The steam-to-carbon ratio (S/C) and the flow rate of feed were constant at 4 and 0.1 ml/min, respectively. The effluent gas was monitored by GC/TCD and the evolution of carbon conversion and product gas distribution as a function of time was studied. Among all catalysts investigated, the one with nominal composition A10C10N1Rnc showed the best performance in steam reforming at 500 °C as indicated by higher and more stable H2 yields achieved regardless the reactant used. In order to investigate the sorption-enhanced steam reforming, three CaO-based CO2 absorbents were synthesized: two derived from calcium acetate with or without MgO support, noted as CAM and CA, respectively, and the other MgO-supported one derived from calcium d-gluconate, denoted as CGM. Results from the 15-carbonation/regeneration-cycle test suggested that the MgO-containing absorbent CAM has the highest CaO molar conversion and stable CO2 absorption capacity. Though significantly higher CO2 absorption capacity was shown from absorbent CA in the first one cycle, CA absorbent soon lost most of the CO2 absorption capacity due to severe sintering. In addition, the CO2 absorption capacity of absorbent CGM might be underestimated due to insufficient carbonation time. The A10C10N1Rnc catalyst and the CAM absorbent were applied in the steam reforming of acetic acid/glycerol mixture at 500°C. However, no significant improvement can be observed in the presence of absorbent CAM
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Umar, Mohammed Ibrahim. "Screening environmental Pseudomonads for characteristics suitable for a bio-engineered oil remediation agent." Thesis, Abertay University, 2016. https://rke.abertay.ac.uk/en/studentTheses/fa731d6c-bbb6-4698-88aa-5405234c3deb.
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Biosurfactants are surface active chemicals expressed by a range of organisms that reduce liquid (aqueous) surface tensions () of aqueous and aqueous-hydrocarbon (oil) mixtures. They are widely used in biotechnology, including agriculture, cosmetics, food, pharmacology and bioremediation, and many new biosurfactants are identified through surveys of bacteria recovered from a variety of environments. In this work, environmental Pseudomonas spp. were screened for biosurfactant production and behaviours determined in order to investigate the limits of biosurfactant activity and potential structural diversity within a phylogenetically related group of bacteria. A total of 355 pseudomonads and Pseudomonas-like isolates were isolated from activated sludge wastewater and potentially petroleum-contaminated soils from road side drainage (SUDS) site. These were phenotypically characterized using a number of growth and behaviour assays, including air-liquid interface biofilm formation in static microcosms and in a column bead system, and shown to be a diverse collection of isolates with a minimal level of biological replication (i.e. little evidence of identical strains recovered more than once in or between samples). Of these, 57 isolates were found to express biosurfactants in vitro by drop-collapse assay and confirmed by quantitative tensiometry. The surface tension of cell-free culture supernatants produced by these isolates was between 24.5 – 49.1 mN m-1, with a minimum theoretical surface tension (Min) of 24.2 mN m-1. This is in agreement with earlier predictions, suggesting a fundamental limit to the ability of bacterial biosurfactants to reduce surface tensions in aqueous systems. This finding suggests that further effort to isolate stronger active surfactants are likely to be wasted, and poses the interesting question of what biological or physical factors limit the production of stronger biosurfactants by bacteria. Differences in biosurfactant behaviour determined by foaming, emulsion and oil-displacement assays were also observed amongst select isolates producing surface tensions of 25 – 27 mN m-1, suggesting structural diversity in the biosurfactants produced. These findings provide a system for selecting biosurfactants for further chemical-structural analyses and future testing for various biotechnology applications where low surface activity, but varied behaviour is required.
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Costa, da Cruz Ana Rita. "Compositional and kinetic modeling of bio-oil from fast pyrolysis from lignocellulosic biomass." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1006/document.
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La pyrolyse rapide est une des voies de conversion thermochimique qui permet la transformation de biomasse lignocellulosique en bio-huiles. Ces bio-huiles, différentes des coupes lourdes du pétrole ne peuvent pas être directement mélangés dans les procédés de valorisation. En effet, en raison de leur forte teneur en oxygène, les bio-huiles nécessitent une étape de pré-raffinage, telle que l’hydrotraitement, pour éliminer ces composants.L’objectif de ce travail est de comprendre la structure, la composition et la réactivité de la bio-huile grâce à la modélisation de données expérimentales. Pour comprendre leur structure et leur composition, des techniques de reconstruction moléculaire basées sur des données analytiques, ont été appliquées, générant un mélange synthétique, dont les propriétés correspondent à celles du mélange. Pour comprendre leur réactivité, l'hydrotraitement de molécules modèles a été étudié: gaïacol et furfural. Pour cela, un modèle déterministe et stochastique a été créé pour chacun d’eux. L’approche déterministe visait à récupérer une gamme de paramètres cinétiques, qui ont ensuite été affinés par l’approche stochastique créant un nouveau modèle. Cette approche a permis de générer un réseau de réactions en définissant et en utilisant un nombre limité de familles et règles des réactions. Finalement, le mélange synthétique a été utilisé dans la simulation stochastique de l’hydrotraitement de la bio-huile, étayée par la cinétique des molécules modèles.En conclusion, ce travail a permis de recréer la fraction légère de la bio-huile et de simuler leur l'hydrotraitement, via les paramètres cinétiques des composés modèles, qui prédisent de manière raisonnable les effluents de l'hydrotraitement de celles-ci, mais sont inadéquat pour le bio-huileFast pyrolysis is one of the thermochemical conversion routes that enable the transformation of solid lignocellulosic biomass into liquid bio-oils. These complex mixtures are different from oil fractions and cannot be directly integrated into existing petroleum upgrading facilities. Indeed, because of their high levels of oxygen compounds, bio-oils require a dedicated pre-refining step, such as hydrotreating, to remove these components.The aim of the present work is to understand the structure, composition and reactivity of bio-oil compounds through modeling of experimental data. To understand the structure and composition, molecular reconstruction techniques, based on analytical data, were applied generating a synthetic mixture, whose properties are consistent with the mixture properties. To understand the reactivity, the hydrotreating of two model molecules was studied: Guaiacol and Furfural. A deterministic and stochastic model were created for each compounds. The deterministic approach intended to retrieve a range of kinetic parameters, later on refined by the stochastic simulation approach into a new model. This approach generates an reaction network by defining and using a limited number of reaction classes and reaction rules. To consolidate the work, the synthetic mixture was used in the stochastic simulation of the hydrotreating of bio-oils, supported by the kinetics of the model compounds.In sum, the present work was able to recreate the light fraction of bio-oil and simulate the hydrotreating of bio-oils, via the kinetic parameters of model compounds, which can reasonably predict the effluents of the hydrotreating of these, but are unsuitable for bio-oil.Fast pyrolysis is one of the thermochemical conversion routes that enable the transformation of solid lignocellulosic biomass into liquid bio-oils. These complex mixtures are different from oil fractions and cannot be directly integrated into existing petroleum upgrading facilities. Indeed, because of their high levels of oxygen compounds, bio-oils require a dedicated pre-refining step, such as hydrotreating, to remove these components.The aim of the present work is to understand the structure, composition and reactivity of bio-oil compounds through modeling of experimental data. To understand the structure and composition, molecular reconstruction techniques, based on analytical data, were applied generating a synthetic mixture, whose properties are consistent with the mixture properties. To understand the reactivity, the hydrotreating of two model molecules was studied: Guaiacol and Furfural. A deterministic and stochastic model were created for each compounds. The deterministic approach intended to retrieve a range of kinetic parameters, later on refined by the stochastic simulation approach into a new model. This approach generates an reaction network by defining and using a limited number of reaction classes and reaction rules. To consolidate the work, the synthetic mixture was used in the stochastic simulation of the hydrotreating of bio-oils, supported by the kinetics of the model compounds.In sum, the present work was able to recreate the light fraction of bio-oil and simulate the hydrotreating of bio-oils, via the kinetic parameters of model compounds, which can reasonably predict the effluents of the hydrotreating of these, but are unsuitable for bio-oil
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Gao, Wenran. "Fuel Properties and Thermal Processing of Bio-oil and Its Derived Fuel Mixtures." Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/75545.
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This thesis reports the fuel properties and thermal processing of bio-oil derived fuel mixtures. Biochar loading level affects fuel properties and ignition behavior of slurry fuels prepared from crude glycerol/methanol/bio-oil (CGMB) blends and biochar, while exhibits little effect on cold flow behavior. Crude glycerol (CG) improves the ignition and cold flow behavior of slurry fuels while has limited effect on fuel properties. Interactions between sugar and lignin-derived oligomers contribute bed agglomeration during bio-oil fast pyrolysis.
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Chapelliere, Yann. "Investigation of the structure-property relationships of hierarchical Y zeolites for the co-processing of bio-oil with vacuum gas oil." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSE1046.
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Le monde fait face à des enjeux climatiques et énergétiques qui impliquent l’utilisation de biomasse, au même titre que d’autres énergies renouvelables, comme des moyens de production d’énergie. Parmi les voies envisagées, l’addition d’huile de pyrolyse au sein de procédés de raffinage déjà existants présenterait l’avantage d’une mise en place rapide et d’une modification structurelle limitée. L’unité de craquage catalytique en lit fluidisé (FCC), valorisant les fractions pétrolières les plus lourdes, est l’unité la plus à même de valoriser des charges biosourcées. Cependant, les premiers tests ont pu révéler la présence de certains freins, tels que l’immiscibilité des charges fossiles et biosourcées, impliquant la mise en place de deux systèmes d’injection indépendants, ou encore une plus forte désactivation des catalyseurs de craquage. Sur ce dernier point, la présence de larges fragments lignocellulosiques, volumineux et riches en oxygène, perturbe le fonctionnement des catalyseurs de FCC. Leur encombrement étant suspecté de limiter leur accès aux sites acides, responsables du craquage catalytique, l’addition de mésopores aux cristaux de zéolites microporeux est une voie de recherche intéressante. Parallèlement à cela, la préparation de matériaux à porosité hiérarchisée, c’est-à-dire alliant l’agencement de plusieurs niveaux de porosité, se développe depuis quelques années. Ces matériaux rentrent parfaitement dans le cadre de l’amélioration de l’accessibilité aux sites acides. Ces travaux de thèse visent ainsi à définir l’impact que peut avoir un processus de hiérarchisation de la porosité sur le craquage catalytique d’un mélange de charges pétrolières fossiles avec une huile de pyrolyse de biomasse. Dans cette optique, une zéolite Y - couramment utilisée pour le craquage catalytique - a été hiérarchisée conformément aux protocoles déjà disponibles dans la littérature. Les caractéristiques structurelles de quatre matériaux ont ensuite été définies, aidant ainsi à la compréhension d’études du transfert diffusionnel, du craquage de molécules modèles et du craquage de charges réelles réalisées par la suite et présentées dans ce manuscrit de thèseFluid Catalytic Cracking (FCC) gasoline represents one third of the global gasoline pool. In order to meet objectives regarding increased renewable share in transportation fuels, the production of a hybrid bio/fossil fuel by co-refining biomass pyrolysis liquids with crude oil fractions in an oil refinery is an achievable approach. Oxygenated molecules, typical of the bio-feedstock, are present in liquids produced from biomass pyrolysis. Because large lignocellulosic fragments could strongly adsorb on the FCC zeolite surface, they may not access catalytic sites or could diffuse very slowly in the microporous network. Hence, for high oxygenated molecule content, co-refining may lead to severe changes in product quality, such as a higher aromaticity, coke and residual oxygenates in the hybrid fuels that are produced. To adjust the reactivity of FCC catalysts towards bio-oil, four Y zeolites with well controlled hierarchical mesoporous – microporous network have been investigated. They mainly vary by the characteristics of the secondary mesoporous network (pore size, mesoporous volume) while their globally similar acidity displays some changes in nature (Lewis/Brønsted). The impact of hierarchical porous structures combined with changes in acidity is studied on catalytic activity and selectivity (e.g., coke formation). The issue of diffusion limitation in line with acidity changes are discussed based on Zero Length Column (ZLC) measurements, pyridine adsorption measurements, catalytic cracking of n-hexane and co-processing of vacuum gas oil and bio-oil in micro-activity test unit
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RODRIGUES, Dauci Pinheiro. "Avaliação da estabilidade térmica do bio-óleo de girassol obtido por craqueamento térmico e termocatalítico: síntese e caracterização." Universidade Federal de Campina Grande, 2014. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/2006.
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A utilização de combustíveis alternativos vem ganhando destaque no mundo inteiro, pois além do petróleo ser uma fonte esgotável de energia, emite grandes quantidades de gases poluentes. Propostas têm surgido para substituição dos combustíveis fósseis, entre elas se destacam os biocombustíveis, a partir de óleos vegetais e gorduras animais. Partindo deste contexto, este trabalho tem como objetivo avaliar a estabilidade térmica do bio-óleo de girassol, obtido por craqueamento térmico e termocatalítico. Inicialmente as amostras do catalisador foram sintetizadas e caracterizadas por DRX, área superficial por adsorção de nitrogénio, FRX, FTIR, TG/DTG/DTA, TPD-NH3, infravermelho por adsorção de piridina e RMN de31P,27Al, e 29Si. Os resultados obtidos pela difratometria de raios-X indicaram que as amostras de SAPO-5 possuem boa cristalinidade, evidenciando que o método de síntese empregado foi eficiente. A acidez das amostras do catalisador nos diversos teores de silício foi avaliada por (TPD-NH3) e infravermelho por adsorção de piridina. Pela TPD-NH3 verificou-se a presença de dois tipos de sítios ácidos, um mais fraco que dessorve amónia em temperaturas mais baixas e outro mais forte que dessorve amónia em temperaturas mais altas. Por meio da adsorção de piridina detectou-se a maior presença de sítios ácidos fracos de Bronsted para todas as amostras analisadas, sendo a amostra S040 a que apresentou maior quantidade de sítios de Bronsted e Lewis. A análise RMN de 29Si indicou para todas as amostras, a presença de mais de um tipo de mecanismo de incorporação do silício à rede de um aluminofosfato, tendo o SM2 ocorrido em maior proporção. Os craqueamentos térmico e termocatalítico do óleo de girassol, realizados da temperatura ambiente a 550°C, em um reator batelada com sistema de destilação simples, forneceram duas frações líquidas orgânicas. A primeira fração coletada em ambos os processos apresentou índice de acidez elevado (170 mg KOH/mg de bio-óleo), indicando que o catalisador não foi efetivo sobre esta fração. Por outro lado, a segunda fração líquida obtida em presença de catalisador apresentou baixo índice de acidez, principalmente aquela obtida nos processos realizados sobre as amostras S025 e S040. Indicando que essas amostras foram mais efetívas no craqueamento secundário do óleo, no qual os ácidos carboxílicos se decompõem gerando hidrocarbonetos. O bio-óleo obtido na segunda fração por ambos os métodos, foi submetido às análises físico-químicas: destilação atmosférica, massa específica, viscosidade cinemática e índice de cetano. Os resultados obtidos indicaram que essas propriedades permaneceram dentro das especificações da ANP para o diesel mineral, tendo o bio-óleo obtido pelo processo de craqueamento termocatalítico propriedades mais adequadas para uso como combustível. A estabilidade térmica do óleo de girassol e dos bio-óleos com e sem a presença de catalisadores foi avaliada utilizando as técnicas TG/DTG/DTA nas razões de aquecimento de 5, 10, 15 e 20(°C.min") em atmosfera de N2. Os resultados obtidos indicaram que os bio-óleos apresentam baixas estabilidades térmicas, necessitando, portanto do uso de aditivo melhorador da estabilidade térmica do bioóleo, para, assim, poder aumentar o tempo de prateleira do mesmo.
The use of alternative fuels is gaining prominence worldwide, because beyond petroleum be an exhaustible source of energy, emits large amounts of polluting gases. Proposals have emerged to replace fóssil fuels, among which stand out biofuels from vegetable oils and animal fats. From this context, this work aims to evaluate the thermal stability of sunflower bio-oil, obtained by thermal and thermo-catalytic cracking. Initially the samples of the catalyst were synthesized and characterized by XRD, textural analysis by nitrogen adsorption, XRF, FTIR, TG/DTG/DTA, TPD-NH3, infrared by pyridine adsorption and 31P, 27A1, and 29Si NMR. The results obtained by X-ray diffraction showed that the samples of SAPO-5 have good crystallinity, indicating that the synthesis method used was efficient. The acidity of the catalyst samples at various silicon contents was evaluated by (TPD-NH3) and infrared by pyridine adsorption. For the TPD-NH3 it was verified the presence of two types of acid sites, a weaker which desorbs ammonia at lower temperatures and another stronger which desorbs ammonia at higher temperatures. By means of the pyridine adsorption was detected greater presence of weak Bronsted acid sites for ali samples analyzed, being the S040 sample which presented the highest amount of Bronsted and Lewis sites. The 29Si NMR analysis indicated for ali the samples the presence of more than one type of mechanism incorporation of the silicon to the network of an aluminophosphate, having the SM2 occurred in greater proportion. The thermal and thermo-catalytic cracking of sunflower oil, performed from room temperature to 550°C in a batch reactor with simple distillation system, provided two organic liquid fractions. The first fraction collected in both processes showed higher index of acidity (170 mg KOH/mg of bio-oil), indicating that the catalyst was not effective on this fraction. In contrast, the second liquid fraction showed low index of acidity, particularly those obtained in the processes performed on the samples S025 and S040. Indicating that these samples were more effective in secondary cracking of the oil, in which the carboxylic acids decompose themselves generating hydrocarbons. The bio-oil obtained from the second fraction by both methods, was subjected to physicochemical analyzes: atmospheric distillation, specific mass, kinematic viscosity and cetane. The results indicated that these properties remain within the specifications of ANP for mineral diesel, having the bio-oil obtained by the thermo-catalytic cracking process, properties more suitable for use as fuel. The thermal stability of sunflower oil and bio-oils with and without the presence of catalyst was evaluated using the techniques TG / DTG / DTA in the heating ratios of 5, 10, 15 and 20 ("C.min1) in atmosphere of N2. The obtained results indicated that sunflower oil and bio-oils are of low thermal stabilities, requiring therefore the use of improver additives of thermal stability of bio-oil, and thus be able to increase the shelf life of the same.