Academic literature on the topic 'Ethylene glycol dehydration'
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Journal articles on the topic "Ethylene glycol dehydration"
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Trifunović, Dragan, Kai Schuchmann, and Volker Müller. "Ethylene Glycol Metabolism in the Acetogen Acetobacterium woodii." Journal of Bacteriology 198, no. 7 (January 19, 2016): 1058–65. http://dx.doi.org/10.1128/jb.00942-15.
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ABSTRACTThe acetogenic bacteriumAcetobacterium woodiiis able to grow by the oxidation of diols, such as 1,2-propanediol, 2,3-butanediol, or ethylene glycol. Recent analyses demonstrated fundamentally different ways for oxidation of 1,2-propanediol and 2,3-butanediol. Here, we analyzed the metabolism of ethylene glycol. Our data demonstrate that ethylene glycol is dehydrated to acetaldehyde, which is then disproportionated to ethanol and acetyl coenzyme A (acetyl-CoA). The latter is further converted to acetate, and this pathway is coupled to ATP formation by substrate-level phosphorylation. Apparently, the product ethanol is in part further oxidized and the reducing equivalents are recycled by reduction of CO2to acetate in the Wood-Ljungdahl pathway. Biochemical data as well as the results of protein synthesis analysis are consistent with the hypothesis that the propane diol dehydratase (PduCDE) and CoA-dependent propionaldehyde dehydrogenase (PduP) proteins, encoded by thepdugene cluster, also catalyze ethylene glycol dehydration to acetaldehyde and its CoA-dependent oxidation to acetyl-CoA. Moreover, genes encoding bacterial microcompartments as part of thepdugene cluster are also expressed during growth on ethylene glycol, arguing for a dual function of the Pdu microcompartment system.IMPORTANCEAcetogenic bacteria are characterized by their ability to use CO2as a terminal electron acceptor by a specific pathway, the Wood-Ljungdahl pathway, enabling in most acetogens chemolithoautotrophic growth with H2and CO2. However, acetogens are very versatile and can use a wide variety of different substrates for growth. Here we report on the elucidation of the pathway for utilization of ethylene glycol by the model acetogenAcetobacterium woodii. This diol is degraded by dehydration to acetaldehyde followed by a disproportionation to acetate and ethanol. We present evidence that this pathway is catalyzed by the same enzyme system recently described for the utilization of 1,2-propanediol. The enzymes for ethylene glycol utilization seem to be encapsulated in protein compartments, known as bacterial microcompartments.
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Hermanns, W., F. Colbatzky, A. Günther, and B. Steiniger. "Ia antigens in plastic-embedded tissues: a post-embedding immunohistochemical study." Journal of Histochemistry & Cytochemistry 34, no. 6 (June 1986): 827–31. http://dx.doi.org/10.1177/34.6.3517152.
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The aim of the present study was to establish a plastic embedding technique that makes possible the immunohistochemical demonstration of class II major histocompatibility complex (MHC) antigens (Ia antigens) in undecalcified joint tissues. Therefore a series of fixatives and dehydrating agents was tested for saving Ia immunoreactivity by post-embedding immunostaining of thin sections (2 microns) of rat tissues that had been embedded in glycol methacrylate (GMA), and by comparing with cryostat sections. An indirect immunoperoxidase and the avidin-biotin complex (ABC) technique were used. Combined with fixation by 4% formaldehyde, dehydration with GMA was found to give the best preservation of Ia antigenicity, followed by dehydration with ethylene glycol. The thinness of tissue sections facilitated the association of Ia antigens with different subcellular compartments in distinct cell populations. These various patterns are described.
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Smith, William B. "Ethylene glycol to acetaldehyde-dehydration or a concerted mechanism." Tetrahedron 58, no. 11 (March 2002): 2091–94. http://dx.doi.org/10.1016/s0040-4020(02)00103-5.
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Yu, Congli, Chao Zhong, Yanmei Liu, Xuehong Gu, Gang Yang, Weihong Xing, and Nanping Xu. "Pervaporation dehydration of ethylene glycol by NaA zeolite membranes." Chemical Engineering Research and Design 90, no. 9 (September 2012): 1372–80. http://dx.doi.org/10.1016/j.cherd.2011.12.003.
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Farda, Eric. "Dehydration Simulation of Natural Gas by using Tri Ethylene Glycol." Journal of Earth Energy Engineering 7, no. 1 (April 2, 2018): 11–18. http://dx.doi.org/10.25299/jeee.2018.vol7(1).981.
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Water content in natural gas poses threat to process facilities such as column distillation. Natural gas from reservoirs usually contains water vapor, the presence of water vapor in gas processing causes bad impact to process facilities. Dry Gas composition data was taken from Salamander Energy. Optimization of natural gas dehydration using Tri Ethylene Glycol was carried out using Aspen HYSYS V8.6 with Peng-Robinson fluid package. The natural gas dehydrating plant was designed with operating conditions of 394 bar and 460C and 10 MMSCFD and 6.8 MMSCFD gas flow rate were inputted. Results obtained from HYSYS simulation shows. Three different TEG flowrates were used for this simulation. Results obtained from simulation that . For the purpose of running the plant economically, the minimum flow rate of TEG which will reduce the water content to within the limit of pipeline specification, is very important and the result obtained showed that a minimum of 3 m3/h of TEG is required to reduce the water content of a gas stream of 10MMSCFD to 6.8lb/MMSCFD, which is within the limit of 6-7lb/MMSCFD, this value when compare to gas plant which uses 15m3/h for the gas stream of 10MMSCFD to achieve the same water content specification is far lower. Values below this flow rate (3.5m3/h) may not reduce the water content to the specified limit.
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Roger, Robert, and Frank C. Harper. "The dehydration of 1-o-tolyl-2.2-diphenyl ethylene glycol." Recueil des Travaux Chimiques des Pays-Bas 56, no. 2 (September 3, 2010): 202–7. http://dx.doi.org/10.1002/recl.19370560216.
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Li, Zhenjun, Bruce D. Kay, and Zdenek Dohnálek. "Dehydration and dehydrogenation of ethylene glycol on rutile TiO2(110)." Physical Chemistry Chemical Physics 15, no. 29 (2013): 12180. http://dx.doi.org/10.1039/c3cp50687h.
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Dabros, Trine Marie Hartmann, Mads Lysgaard Andersen, Simon Brædder Lindahl, Thomas Willum Hansen, Martin Høj, Jostein Gabrielsen, Jan-Dierk Grunwaldt, and Anker Degn Jensen. "Hydrodeoxygenation (HDO) of Aliphatic Oxygenates and Phenol over NiMo/MgAl2O4: Reactivity, Inhibition, and Catalyst Reactivation." Catalysts 9, no. 6 (June 12, 2019): 521. http://dx.doi.org/10.3390/catal9060521.
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This study provides new insights into sustainable fuel production by upgrading bio-derived oxygenates by catalytic hydrodeoxygenation (HDO). HDO of ethylene glycol (EG), cyclohexanol (Cyc), acetic acid (AcOH), and phenol (Phe) was investigated using a Ni-MoS2/MgAl2O4 catalyst. In addition, HDO of a mixture of Phe/EG and Cyc/EG was studied as a first step towards the complex mixture in biomass pyrolysis vapor and bio-oil. Activity tests were performed in a fixed bed reactor at 380–450 °C, 27 bar H2, 550 vol ppm H2S, and up to 220 h on stream. Acetic acid plugged the reactor inlet by carbon deposition within 2 h on stream, underlining the challenges of upgrading highly reactive oxygenates. For ethylene glycol and cyclohexanol, steady state conversion was obtained in the temperature range of 380–415 °C. The HDO macro-kinetics were assessed in terms of consecutive dehydration and hydrogenation reactions. The results indicate that HDO of ethylene glycol and cyclohexanol involve different active sites. There was no significant influence from phenol or cyclohexanol on the rate of ethylene glycol HDO. However, a pronounced inhibiting effect from ethylene glycol on the HDO of cyclohexanol was observed. Catalyst deactivation by carbon deposition could be mitigated by oxidation and re-sulfidation. The results presented here demonstrate the need to address differences in oxygenate reactivity when upgrading vapors or oils derived from pyrolysis of biomass.
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Li, Zheng, Jin-Lan Yu, Jing-Ya Yang, Sheng-Yi Shi, and Xi-Cun Wang. "Polymer-supported Dichlorophosphate: A Recoverable New Reagent for Synthesis of 2-amino-1,3,4-thiadiazoles." Journal of Chemical Research 2005, no. 5 (May 2005): 341–43. http://dx.doi.org/10.3184/0308234054323913.
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Poly(ethylene glycol) (PEG) supported dichlorophosphate was efficiently used as a recoverable new dehydration reagent for rapid synthesis of 2-amino-5-substituted-1,3,4-thiadiazoles under microwave irradiation and solvent-free condition by reactions of thiosemicarbazide with aliphatic acids, benzoic acid, aryloxyacetic acids or furan-2-carboxylic acids.
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Yang, Jie, Ruo-Nan Zhang, Dong-Jie Liu, Xu Zhou, Tatsuya Shoji, Yasuyuki Tsuboi, and Hu Yan. "Laser trapping/confocal Raman spectroscopic characterization of PLGA-PEG nanoparticles." Soft Matter 14, no. 40 (2018): 8090–94. http://dx.doi.org/10.1039/c8sm01364k.
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We have immobilized poly(ethylene glycol) (PEG) on the surfaces of poly(lactic-co-glycolic acid) (PLGA) nanoparticles by two different chemical methods, i.e., SOCl2 halogenate-alcoholysis and DCC dehydration. The PEG-immobilized PLGA nanoparticles were precisely characterized by the laser trapping/confocal Raman spectroscope.
Dissertations / Theses on the topic "Ethylene glycol dehydration"
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Hýža, Bohumil. "Možnosti zpracování odpadů glykolu a glycerolu na účelové látky." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217075.
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At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. Then, here are the proposed new procedures for processing waste glycerol and glycol, which were conducted in the experimental part of the thesis. There are described the ion exchange properties of the cation exchangers and also properties of salts generated by neutralization of NaOH in the waste glycerol with organic acids and CO2. There is also described wood protection, properties of ethylene glycol as coolant and properties of boroglycerols and boroglycols as protection for wood and mechanism of their preparation. Then there is described a mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured and then was measured the amount of NaOH in the waste glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol. There is also discussed technological applicability of the methods used in practice.
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Hýža, Bohumil. "Možnost zpracování glycerolové fáze z výroby bionafty." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217043.
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The aim of this thesis was to introduce and apply the possibilities of using waste glycerol from biodiesel production and partly waste low-stiffen coolant from cars that could be applied in industry. At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. There are described the ion exchange mechanism, ion exchange resin properties and the properties of the acids and salts generated by neutralization with NaOH contained in the waste glycerol. Also is described herein the wood protection and properties of ethylene glycol coolants and properties of boroglycerol and boroglycol as protection for wood and mechanism of their preparation. Next is described the mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured, then was measured the exact amount of NaOH in the glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol.
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Zhang, Ying. "Layer-by-layer Self-assembly Membranes for Solvent Dehydration by Pervaporation." Thesis, 2013. http://hdl.handle.net/10012/8066.
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In this study, polyelectrolyte membranes were prepared by layer-by-layer self-assembly on top of an interfacially polymerized polyamide substrate, and these thin-film-composite membranes were studied for pervaporative dehydration of ethylene glycol, ethanol and isopropanol.
The performance of composite membranes based on polyethylenimine/poly(acrylic acid) (PEI/PAA) multilayers on a polyamide substrate showed good selectivity and stability for ethylene glycol dehydration. In order to understand the formation process of the polyelectrolyte multilayers, the growth of polyelectrolyte multilayers fabricated on the inner surface of cuvette was investiagted. The membrane surface became increasingly hydrophilic with an increase in the number of polyelectrolyte double layers, which favored water permeation for pervaporative dehydration of organic solvents. Water contact angle on the membrane surface decreased from 68?? to 20?? when 7 polyelectrolyte bilayers were deposited on the polyamide substrate.
Although the (PEI/PAA) based polyelectrolyte membranes showed good performance for dehydration of ethylene glycol, these membranes did not perform well for the dehydration of ethanol and isopropanol at relatively high feed alcohol concentrations. This was found to be caused by insufficient stability of PEI/PAA bilayers and the polyamide substrate in the ethanol and isopropanol. To improve the performance of the composite membranes for dehydration of ethanol and isopropanol, the outermost surface layer was deposited with PEI, followed by crosslinking. A further improvement in the membrane selectivity was accomplished by substituting the PEI with partially protonated chitosan in the last few polyelectrolyte bilayers during membrane fabrication. It was demonstrated that using interfacially polymerized polyamide membrane as a substrate, polyelectrolyte membranes with less than 8 bilayers could be fabricated for the dehydration of alcohol and diol. This represents a siginificant advancement as a large number of polyelectrolyte bilayers (as many as 60) are often needed.
Glutaraldehyde crosslinked polyelectrolyte self-assembled membranes comprising of chitosan and PAA were also prepared for isopropanol/water separation. The resulting membrane showed stable performance with good permeation flux and separation factor. The effects of crosslinking conditions (e.g., concentration and temperature of crosslinking agent, and crosslinking time) on the membrane performance were studied.
Alternatively, using PEI as polycation, when anionic PAA was substituted with alginate in the last few polyelectrolyte bilayers during membrane fabrication, stable membranes with a good performance were obtained without the need of chemical crosslinking. The polyethylenimine/alginate self-assembly membranes showed good selectivity and stability for dehydration of ethanol. For instance, a permeation flux of 0.24 kg/(??? h) and a separation factor of 206 were obtained at room temperature at 10 wt% feed water concentration with a membrane comprising of 10 double layers of polyelectrolytes.
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Du, Runhong. "Studies on Poly(N,N-dimethylaminoethyl methacrylate) Composite Membranes for Gas Separation and Pervaporation." Thesis, 2008. http://hdl.handle.net/10012/3741.
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Membrane-based acid gas (e.g., CO2) separation, gas dehydration and humidification, as well as solvent dehydration are important to the energy and process industries. Fixed carrier facilitated transport membranes can enhance the permeation without compromising the selectivity. The development of suitable fixed carrier membranes for CO2 and water permeation, and understanding of the transport mechanism were the main objectives of this thesis.
Poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) composite membranes were developed using microporous polysulfone (PSF) or polyacrylonitrile (PAN) substrates. The PDMAEMA layer was crosslinked with p-xylylene dichloride via quaternization reaction. Fourier transform infrared, scanning electron microscopy, adsorption tests, and contact angle measurements were conducted to analyze the chemical and morphological structure of the membrane. It was shown that the polymer could be formed into thin dense layer on the substrates, while the quaternary and tertiary amino groups in the side chains of PDMAEMA offered a high polarity and hydrophilicity.
The solid-liquid interfacial crosslinking of PDMAEMA led to an asymmetric crosslinked network structure, which helped minimize the resistance of the membrane to the mass transport. The interfacially formed membranes were applied to CO2/N2 separation, dehydration of CH4, gas humidification and ethylene glycol dehydration. The membranes showed good permselectivity to CO2 and water. For example, a CO2 permeance of 85 GPU and a CO2/N2 ideal separation factor of 50 were obtained with a PDMAEMA/PSF membrane at 23oC and 0.41 MPa of CO2 feed pressure. At 25oC, the permeance of water vapor through a PDMAEMA/PAN membrane was 5350 GPU and the water vapor/methane selectivity was 4735 when methane was completely saturated with water vapor. On the other hand, the relative humidity of outlet gas was up to 100 % when the membrane was used as a hydrator at 45oC and at a carrier gas flow rate of 1000 sccm. For used for dehydration of ethylene glycol at 30oC, the PDMAEMA/PSF membrane showed a permeation flux of ~1 mol/(m2.h) and a permeate concentration of 99.7 mol% water at 1 mol% water in feed.
This work shows that the quaternary and tertiary amino groups can be used as carriers for CO2 transport through the membrane based on the weak acid-base interaction. In the presence of water, water molecules in the membrane tend to form a water "path" or water "bridge" which also help contribute to the mass transport though the membrane. In addition, CO2 molecules can be hydrated to HCO3-, which reaction can be catalyzed by the amino groups, the hydrated CO2 molecules can transport through the water path as well as the amino groups in the membrane. On the other hand, for processes involving water (either vapor or liquid) permeation, the amino groups in the membrane are also helpful because of the hydrogen bonding effects.
Book chapters on the topic "Ethylene glycol dehydration"
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Elyassini, J., Q. T. Nguyen, and J. Néel. "PREPARATION AND STUDY OF POLYVINYL ALCOHOL)-POLY(ETHYLENE GLYCOL) BLEND FILMS IN DEHYDRATION OF ETHANOL BY PERVAPORATION." In Synthetic Polymeric Membranes, edited by Blahoslav Sedláček and Jaroslav Kahovec, 507–14. Berlin, Boston: De Gruyter, 1987. http://dx.doi.org/10.1515/9783110867374-050.
Full textConference papers on the topic "Ethylene glycol dehydration"
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Hartanto, Dhoni, Akhmad Sutrisno, Viona Widya, Asalil Mustain, Prima Astuti Handayani, Haniif Prasetiawan, Achmad Chafidz, and Ianatul Khoiroh. "Simulation of the Extractive Distillation using Ethylene Glycol as an Entrainer in the Bioethanol Dehydration." In The 7th Engineering International Conference (EIC), Engineering International Conference on Education, Concept and Application on Green Technology. SCITEPRESS - Science and Technology Publications, 2018. http://dx.doi.org/10.5220/0009013004500454.
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Hartanto, Dhoni, Akhmad Sutrisno, Viona Widya, Asalil Mustain, Prima Astuti Handayani, Haniif Prasetiawan, Achmad Chafidz, and Ianatul Khoiroh. "Simulation of the Extractive Distillation using Ethylene Glycol as an Entrainer in the Bioethanol Dehydration." In The 7th Engineering International Conference (EIC), Engineering International Conference on Education, Concept and Application on Green Technology. SCITEPRESS - Science and Technology Publications, 2018. http://dx.doi.org/10.5220/0009013004620466.
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Mahmoud, Mohamed, Ahmed Alsalman, and Hassan Almalki. "Novel Sample Pretreatment to Determine Iron Counts in Sour Glycol Streams by Spectrophotometer." In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21372-ms.
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Abstract Determination of Iron Content in Triethylene glycol (TEG) samples is a very important indicator in measuring the system corrosion rate in oil and gas facilities. This study employed the application of an alternative/easy and reliable test method, which involved the use of a spectrophotometer for quantification of Iron concentration in tri ethylene glycol samples, that are used in sour gas dehydration units, rather than the sophisticated technique of Inductively Coupled Plasma Optical Emission Spectroscopy, ICP-OES. The main challenge was how to eliminate/minimize the significant interference from the carryover condensate hydrocarbons, BTEX, H2S and amine additives, which cause either precipitation with spectrophotometer reagents or turbid samples. The sample pretreatment process included: 1 - Sample digestion with dilution to eliminate the dissolved acid gases and the dissolved BTEX from the sample in acidic medium; 2 - pH adjustment from 9 – 10.5 to eliminate the amine additives interference with spectrophotometer reagents and 3 – Application of standard addition technique with certified reference material for iron with dilution, to reach the spectrophotometer detection limit and give intense color with more UV absorbance. The method was validated against ICP-OES and the results variance were within 10% acceptance criteria.
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Cárcel, Juan A., Daniele Merone, Domenico Colucci, Davide Fissore, and Neus Sanjuán. "Energy analysis of an ultrasound-assisted atmospheric freeze-drying process for food." In 21st International Drying Symposium. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/ids2018.2018.7888.
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Power ultrasounds have been proposed and extensively investigated as an effective way to speed up the atmospheric freeze-drying process, thus making this dehydration process attractive from an industrial viewpoint. Nevertheless, a rigorous investigation on the impact of power ultrasounds on the energy consumed by the process is still missing. This paper aims to investigate this issue. Apple, carrot and eggplant were chosen as representative products with different textures and water content. A mathematical model of the whole plant required to carry out the atmospheric ultrasound-assisted drying process was developed to assess the effect of the operating conditions on the energy consumption. Model parameters were tuned on the basis of the results obtained in a pilot-scale unit, thus allowing the use of the model to simulate the whole industrial dehydration process. Life Cycle Assessment (LCA) was used as a complementary tool to gain an insight on the environmental impact of the process. Results showed that due to differences in the water diffusivity for the analyzed products, substantial differences in energy consumption can be highlighted. In fact, when the water diffusivity increases, the capacity of the material to move water away also increases and the time to obtain a dry product is thus reduced. Moreover, although the use of ultrasound causes an increase in the hourly energy consumption (kWh·h-1), the total energy consumption of the whole process (kWh) is lower, since the total operation time is reduced. The LCA results highlighted the cooling system as the most critical stage for all the impact categories studied. This is mainly due to the use of ethylene glycol and R-404 in the refrigeration cycle. Nevertheless, when dehydrating low porosity products the energy consumption of the air dryer increased and this stage becomes, the most critical from an environmental point of viewKeywords: atmospheric freeze-drying, ultrasounds, process modeling, LCA.
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Balk, Wouter F., and Kees Tjeenk Willink. "Subsea Hydrocarbon Processing and Treatment: Twister Subsea." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49199.
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Twister™ is an innovative gas conditioning technology which is now generally accepted for natural gas applications. Condensation and separation at supersonic velocity provides some unique benefits. The extremely short residence time (∼ 2ms) prevents hydrate problems, and eliminates the requirement for chemicals and associated regeneration systems. The simplicity and reliability of a static device, with no rotating parts, operating without chemicals, ensures a simple, environmentally friendly facility, with high availability. Previous studies have confirmed that Twister is a key enabler for subsea gas conditioning, enabling direct sales gas export, without the need for topside facilities. The objective of this paper is to present the results of a recent study which evaluates the technical feasibility of using Twister technology for subsea dehydration and hydrocarbon dew-pointing. Four Twister subsea gas production scenarios were studied. Different gas compositions were used to simulate both lean and rich gas reservoirs. Four different process schemes were simulated using UniSIM© and evaluated for each subsea scenario. The process schemes include a Chemical-free, MEG inhibited, a Hybrid and a Liquid Re-injection scheme. The Chemical-free and Hybrid schemes use electricity to prevent hydrate blockage. The MEG inhibited scheme utilizes MEG (Mono-Ethylene Glycol) for hydrate inhibition. This scheme requires some 85% less MEG than wet-gas evacuation under the same production conditions. The Hybrid scheme combines these two processes, and injects MEG after bulk water removal. The Hybrid system can operate using significantly less MEG than that required for the MEG inhibited process, and some 95% less than wet-gas evacuation. Liquid Re-injection produced on-spec gas, but wastes part of the value in the gas stream, as well as MEG. It is concluded that the Hybrid and Chemical-free schemes require some additional subsea technology, which is not yet available. The MEG inhibited scheme, however, uses available subsea technology and can be applied to create on-specification gas ready for direct subsea pipeline export, using available technology. Subsea compression will be required somewhat earlier when compared to wet-gas evacuation. This apparent disadvantage is however overcome by the elimination of platform required for production, the elimination of long multiphase gas lines with inherent pressure losses and overall flow assurance improvement.