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1
Novotný, Jiří. "Eliminace zápachu na stokové síti." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372299.
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The diploma thesis focusses on the elimination of odor in the sewer system. Firstly, the paper contains the research in problematics of the origin, control and risks of the hydrogen sulfide for humans as well as for the sewer system. Secondly, the paper describes methods for hydrogen sulfide removal from water, air and in addition to that the selected sorbents are described in detail. Practical part deals with sorbent testing for hydrogen sulfide removal in laboratory environment. The practical part also follows up the odor in the particular area through sorption on sewer filters. From the measured data and from the results of the laboratory analyzes the consequences of the odor are evaluated and recommendations for the operator are presented.
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Bariyeva, Aizat. "Optimalizace adsorpce kyseliny ferulové na různých typech adsorbentů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401937.
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This thesis deals with optimalization processes of adsorption of ferulic acid on different types of sorbents. Specifically, was used the activated carbon as a sorbent of heterogeneous character and Amberlyst A-21 and Amberlit XAD-16 as macroporous polymer sorbents. The ferulic acid is fully characterized in the theoretical part and are discussed the problems of adsorption processes. To determination of the phenolic acid were used UV-VIS and HPLC instrumental methods. The main aim of the experimental part is to optimize various parameters of adsorption, including the construction of adsorption isotherms, determination of maximum adsorption capacity of individual sorbents, study of kinetics and mechanisms of adsorption. Determination of the influence of salt was studied to assess the impact of the inorganic salts on the ferulic acid adsorption capacity. Based on these parameters, was carried out determination of an optimal pH value on 3, with an optimal adsorbent load (m/V ratio = 0,009 gml-1) and a contact time of 50 min for all three adsorbents. Equilibrium studies described by adsorption isotherms and the Langmiur model fitted the best, and the maximum adsorption capacities were determined for all three sorbents with 150,4 mgg-1 for activated carbon, 209,1 mgg-1 for Amberlyst A-21 and 82 mgg-1 for Amberlyte XAD-16. In the study of kinetic models was selected pseudo-second model for all three adsorbents, which correlated with the results obtained by the Langmuir isotherm. The decrease in adsorption capacity in the determination of NaCl influence was 4 % for activated carbon, for macroporous polymer sorbents was decreased by 52 % and 55 % for Amberlyst A-21 and Amberlyt XAD-16 respectively. In a selectivity test under optimized conditions, adsorption strength increased in the order of sinapic acid ferulic acid p-coumaric acid for polymeric sorbent XAD-16 and activated carbon. For the A-21 sorbent the adsorption strength increased in the order of p-coumaric acid ferulic acid sinapic acid. The results of the work indicate the suitability of all three sorbents for the phenolic acid adsorption.
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Žíla, Radim. "Možnosti odstranění zápachu na stokové síti." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392218.
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The diploma thesis focuses on the possibility of removing odor on the sewer network. The first part of the research describes how the odor is generally perceived and what legislation regulates its quantity in the air. The second part of the research focuses on problems of formation of smelting sulfate on the sewer network. This section describes the formation of sulfane as a major component of odor. Further disclosed are methods for its removal, and the ways in which the odor is measured. The practical part deals with laboratory testing of pre-selected fillings in order to determine their ability to remove odorous sulfane. In the second part, on-line measurements are made to determine the causes of sulphan formation in a given location.
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Mach, Václav. "Tuhé pěny založené na acetalizovaném PVAl." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216426.
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This diploma thesis deals with the preparation of solid hydrophilic sponges made of acetalized PVAl. The sponges were produced by foaming by gaseous reaction by-product. The experimental work also includes the study of active compound immobilization into the sponge (finely ground lignite as a heavy metal sorbent).
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Venkataramakrishnan, Rajesh. "Simulation studies on chemical effects of additives in in-duct injection processes." Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1179863657.
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Brannvall, Evelina. "Sunkiųjų metalų ir naftos produktų kelio aplinkoje tyrimai ir mažinimas naudojant gamtinius sorbentus." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060601_153906-38716.
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The pollution by heavy metals in the roadside soil alteration tendency was thoroughly investigated by applying the complex experimental and statistical environmental analysis and means for pollution by heavy metals and petroleum products reduction by natural zeolite and vermiculite were evaluated and developed. To reach the novelty it was: • The roadside soil pollution by heavy metals, it’s dangerous and pollution variation tendencies were investigated. • The suitability of natural zeolite for heavy metal removal from soil and aquatic solutions was proved. • The suitability of natural zeolite and vermiculite for petroleum products removal from aquatic solutions was proved.
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Szkandera, Roman. "Vývoj techniky difúzního gradientu v tenkém filmu (DGT) pro stanoveni rtuti ve vodných systémech." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233340.
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The theoretical part of this doctoral thesis deals with determination of mercury and its species in aquatic systems. Special attention is paid to the use in situ sampling technique diffusive gradients in thin films technique (DGT) and its development. Current resin gels used for determination of mercury by DGT technique Duolite GT-73, Chelex-100 and Spheron-Thiol are described. Moreover, new types of resin gels including Iontosorb AV modified by imidazole or 6-mercaptopurine and commercially available titanium dioxide. Preparations of resin gels and their basic tests in model solution according to DGT Research are described. Mercury accumulation in relation to time and basic recovery test were tested and capacity of resins was determined. All tested resins meet the requirements of basic DGT Research tests and relative standard deviations of mercury in recovery tests were lower than 10 %. The sorption capacity of resins varied from 1,5 to 6 µmol.l-1 and decreased in following order: Duolite GT-73 > ISAV-IM > Chelex-100 > Spheron-Thiol > TiO2 > ISAV-MP. Mercury sorption on resins was investigated under conditions similar to those in natural waters. It was found that the ionic strength commonly occurring in natural waters does not affect the determination of mercury. The presence of chlorides significantly affects the determination of mercury using DGT with titanium dioxide and therefore this sorbent can not be recommended for the determination of mercury in sea waters. The accumulated amount of mercury, depending on the pH shows that all the sorbents can be used in natural waters with pH in the range form 4 to 8. Mercury sorption is most affected by the presence of humic acids, especially at ion-exchange resins containing other than thiol functional groups. The exception is titanium dioxide for which physical sorption of humic acid metal complexes is typical. Cadmium and copper in model solutions in the molar balance of the excess mostly influenced the sorption of mercury on Chelex-100 and Spheron-Thiol resins. After laboratory tests, the DGT units with studied sorbents were used for the determination of mercury in natural waters of South Moravia (Svratka, Jihlava and Svitava river). Mercury concentration determined using DGT units containing Duolite GT-73 resin was comparable to the total dissolved concentration of mercury in river water provided by direct determination using AAS technique. Order of magnitude smaller concentrations than the total dissolved mercury concentration were found using DGT containing Spheron-Thiol and ISAV-MP resins. These sorbents are probably able to capture only mercury present in the form of labile complexes. This can be used for speciation analysis if more DGT units with different resins are deployed together. Subtracting the measured DGT Spheron-Thiol or ISAV-MP concentrations from the DGT Duolite GT-73 concentration, information about the amount of mercury present in the form of stabile complexes can be obtained. The amount of mercury determined after application of DGT units containing ISAV-IM, Chelex 100 or TiO2 can probably represent the mercury fraction bound in even weaker complexes than fraction determined by Spheron-Thiol and ISAV-MP DGT.
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Iyer, Mahesh Venkataraman. "High temperature reactive separation process for combined carbon dioxide and sulfur dioxide capture from flue gas and enhanced hydrogen production with in-situ carbon dioxide capture using high reactivity calcium and biomineral sorbents." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1135961929.
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Henning, D. S. (Dominique S. ). "Adsorption of bilirubin of polymer sorbents." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72026.
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Adsorption of bilirubin from aqueous buffer (pH = 7.8) by PVP, by cholestyramine and by amino acid containing pendants, which have been immobilized onto a polystyrene (Merrifield) resin or a water swellable polyamide resin using the solid phase peptide synthesis methods, have been studied. The adsorption of bilirubin by the pendants on the Merrifield resin was minimal while PVP and cholestyramine adsorbed some bilirubin. However, the best adsorbents were the immobilized amino acids on a water swellable polyamide resin.A systematic study of the effect of the changes in the amino acid composition of the pendant, both in type and number, on the adsorption by the polyamide resins indicates that the change density, contributed by the R groups of the amino acids in the pendant, is the major factor in the adsorption process. However, some adsorption also occurs at the (alpha)-amino groups. Effects due to the conformation of the peptide chains are also indicated. Of the resins studied, those with peptide pendants containing arginine or lysine form the most efficient adsorbents for bilirubin in aqueous buffer solution.
Studies of the adsorption of bilirubin from bilirubin solutions containing bovine serum albumin as well as studies of desorption of bilirubin from the resins by bovine serum albumin indicates that some resins containing arginine in the pendants can successfully compete with albumin. Stoichiometric binding constants obtained for the polyamide resins by the method of Klotz are of the order of 1 x 10('3) M('-1) to 86 x 10('3) M('-1). These binding constants are lower than that of the reported values for the first binding site of bilirubin on albumin by a factor of 10('1) to 10('4) and lower by a factor of 10 to 10('3) than the values reported for the second binding site.
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Arthur, Lia Frieda. "Silicate sorbents for flue gas cleaning /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Luo, Yuzhong. "Membrane extraction with a sorbent interface." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq38251.pdf.
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Masselot, Véronique. "Influence des stabilisants sur la cristallisation d'un semi-liquide alimentaire : Application à la congélation des sorbets." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASB021.
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Un sorbet est un dessert congelé et aéré, fabriqué à partir d’un mix constitué de jus de fruit concentré, de sucres et de stabilisants. L’étape la plus critique du procédé de fabrication des sorbets est l’étape de congélation-foisonnement qui a lieu dans un échangeur de chaleur à surface raclée (ECSR) ; c’est lors de cette étape que se forment les cristaux de glace et que l’air est introduit tandis que la solution résiduelle non congelée se concentre en sucres et en stabilisants. La qualité du produit final est fortement liée à la quantité initiale et à la taille des cristaux de glace formés dans l’ECSR ; ils doivent être les plus nombreux et les plus petits possibles. L’objectif scientifique de cette thèse est une meilleure compréhension de l’influence des stabilisants sur la microstructure (taille et nombre de cristaux et de bulles d’air) formée pendant la congélation d’un sorbet.Les propriétés rhéologiques du mix de sorbet avant sa congélation et de la solution résiduelle non congelée ont été explorées et quantifiées en fonction du type de stabilisant utilisé (CMC, HPMC, LBG). Des études de leurs propriétés tensioactives et de la diffusion des molécules d’eau ont été menées et les propriétés thermiques d’équilibre du mix ont été analysées. La microstructure de ces sorbets a été étudiée in situ au cours du procédé de congélation et ex situ en fin de congélation à l’aide d’outils de caractérisation performants (FBRM, Microtomographie à rayons-X et Cryo-MEB).L’ensemble des études réalisées a permis une meilleure compréhension de l’influence des molécules stabilisantes sur la mise en place de la microstructure d’un sorbet et notamment sur la taille et le nombre des cristaux de glace et des bulles d’air. Seul l’HPMC influence significativement la quantité d’air incorporée d’une part, et le nombre et la taille des cristaux de glace d’autre part. Il semblerait que ce stabilisant, en augmentant la fraction d’air, diminue la croissance des cristaux de glace. Les bulles d’air agiraient comme des barrières physiques lors de la congélation. La viscosité des mixes ou solution résiduelles, et la diffusion de l’eau dans ces systèmes ne sont pas des facteurs qui contrôleraient la cristallisationA sorbet is a frozen and aerated dessert made from a mix of concentrated fruit juice, sugars and stabilizers. The most critical step in the manufacturing process of sorbets is the freezing-foaming step that takes place in a scraped surface heat exchanger (SSHE). During this step, ice crystals are generated and air bubbles are introduced while the unfrozen residual solution concentrates in sugars and stabilizers. The quality of the final product is strongly related to the quantity and size of ice crystals formed in the SSHE; they must be numerous and as small as possible. The scientific objective of this thesis is a better understanding of the influence of stabilizers on the microstructure (number and size of ice crystals and air bubbles) formed during the freezing process of a sorbet.The rheological properties of the sorbet mix before freezing and of the unfrozen residual solution were explored and quantified according to the stabilizer added (CMC, HPMC, or LBG). Studies of their surfactant properties and of the diffusion of water molecules were carried out and the thermal equilibrium properties of the mix were analyzed. The microstructure of sorbets was characterized in situ during the freezing process and ex situ at the end of freezing using high-performance characterization tools (FBRM, X-ray micro-computed tomography and Cryo-SEM).This study provides a better understanding of the influence of stabilizers on the establishment of the microstructure of a sorbet and in particular on the size and number of ice crystals and air bubbles. HPMC is the only stabilizer that influences the amount of air incorporated, and also the number and size of ice crystals. It appears that this stabilizer, by increasing the amount of air, decreases the growth of ice crystals. The air bubbles would act as physical barriers during freezing. The viscosities of the mix or the unfrozen residual solution, and water diffusion do not influence the crystallization in these systems
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Salameh, Yousef. "Arsenic removal from wastewater using dolomitic sorbents." Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.579772.
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Dolomite and charred dolomite have been evaluated for use in the removal of dissolved arsenic anions (arsenate and arsenite) from wastewaters. Experimental equilibrium isotherm investigations, kinetic experiments and fixed-bed column experiments have been used to assess the uptake from a wide range of aqueous arsenic solutions, employing both dolomite and thermally processed (charred) dolomite. Scanning electron microscopy, X-ray diffraction, FTIR analysis, Zetasizer (size analysis), mercury porosimetry and inductively coupled plasma atomic emission spectrometry (ICP-AES) have been utilized to aid in the evaluation of the dolomitic materials as adsorbents. Equilibrium experimental data have been analyzed using Langmuir, Freundlich, Henry and Redlich-Peterson isotherm models. Kinetic data have also been analyzed using elementary first and second reaction models and an intra particle diffusion model. The data from the models have been used to help determine the mechanism of arsenic removal. Dolomite and its thermally activated dolomites have shown potential as a cost effective material for use in the removal of arsenic from drinking water. Modifying the surface of the dolomite by charring, helped to overcome obstacles encountered with the adsorption of arsenic onto raw dolomite. The charred dolomite shows significant potential in removing As (III) from aqueous solutions and has been shown to operate effectively under a wide pH range. The thesis provides evidence for ion exchange, adsorption and precipitation mechanisms, to account for the removal of arsenic from aqueous solutions using dolomite and charred dolomite.
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Chiang, Ray-Kuang. "Calcium-based sorbents for flue gas desulfurization." Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1062008694.
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Bilton, Matthew William. "Nanoparticulate hydroxyapatite and calcium-based CO2 sorbents." Thesis, University of Leeds, 2012. http://etheses.whiterose.ac.uk/3847/.
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This thesis is focused on the development of synthesis and characterisation protocols for two different nanoparticulate materials; hydroxyapatite (HA), a biomaterial well recognised as chemically akin to human bone, and CaO, a material often used for the sequestration of CO2 at elevated temperatures. For the analysis of these materials various bulk and particle level characterisation techniques have been employed, which are complemented by the versatile analytical methods available in the transmission electron microscope (TEM). The first chapter of results reveal that a hydrothermal synthesis route achieved phase-pure nanoparticulate HA with Ca/P atomic ratios close to the stoichiometric target (1.67). Impure HA nanopowders were produced by a sol-gel synthesis route with analysis by X-ray diffraction (XRD) revealing secondary phases of calcium phosphates, CaCO3 and CaO. The Ca/P ratios of each powder were determined at the particle level using TEM with energy dispersive X-ray spectroscopy (TEM-EDX), having first established a threshold electron fluence below which significant electron-beam-induced alteration of the composition of HA does not occur. Results showed a greater variability of particle composition from the sol-gel preparation route compared to the hydrothermal route. This technique provides results in reasonable agreement to bulk Ca/P ratio analysis carried out by X-ray fluorescence (XRF) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The second component of the thesis relates to the production of nanoparticulate CaO powder sorbents for the sequestration of CO2 gas. The CaO nanopowders were produced by the thermal decomposition of calcium acetate hydrate (CaAc); this process was analysed by thermogravimetric analysis (TGA) and by in-situ hot-stage XRD. The CO2 uptake capability of the CaO powder sorbents was analysed by TGA following the reaction: CaO + CO2 ↔ CaCO3 Results showed a molar conversion ratio, χ (of CaO to CaCO3) of 0.92, after 15 minutes of carbonation with structural analysis by SEM and TEM showing consistent growth and densification of rounded CaCO3 crystals upon carbonation. Multiple cycles of carbonation and decarbonation were then carried out by TGA to investigate sorbent regenerability. A 0.32 decrease in χ was found after 9 cycles which is attributed to the sintering (reduction in surface area) of the sorbent with progressive decarbonations at 800 °C. Structural analysis of decarbonated samples extracted from the TGA, by XRD, SEM and TEM, highlighted the issue of sorbent hydration upon storage, sample preparation and analysis. A TEM based technique has been developed for the structural analysis of multicycle CO2 capture using an ex-situ environmental cell (E-cell). This technique allows for multicycle capture to be carried out and then analysed in the TEM with minimal exposure to the atmosphere, therefore providing a closer microstructural match to what occurs in the TGA. Results showed that slow, low-vacuum decarbonation (in the E-cell) creates a densified ‘skeleton’ of CaO, consistent with the drop in capture capacity observed by TGA. Finally, modifications of CaO sorbents using spacer materials has been carried out with the aim of declining the decay in sorbent performance during multiple cycles of carbonation and decarbonation in the TGA. Promising results were found using CaO sorbents modified a commercial YSZ powder and also with CaZrO3/ZrO2.
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Petrie, James. "Sulphur sorbent particle effects in fluidised combustion." Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/9628.
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Bibliography: leaves 132-137.An overall process model is presented for the capture of sulphur dioxide by calcareous sorbents in a fluidised bed combustor for a feed of arbitrary size distribution. The description of sorbent sulphation kinetics, particle attrition and elutriation effects incorporated in this model is supported by experimental data for a wide range of South African sorbents. The sulphation of sorbent particles is described by a simple, two-parameter, kinetic model. No loss in physical relevance is incurred when the decrease in reaction rate with time is given by a negative exponential term. Both sulphation rate and capacity are shown to be functions of sorbent type. The sulphation propensity of the 16 South African samples is correlated against their geologic description. Sorbent properties such as porosity, crystallinity and topography, which affect sulphation capacity directly, are functions of geologic age. It is possible to make a first order assessment of sorbent potential simply from this geologic data. Sorbent attrition, caused by the continuous movement of particles within the combustor, is greatest for deep beds of soft friable material. Most of the attrition takes place in the distributor region where jetting action is important. The attrition model reflects an explicit dependence on fluidising velocity, bed depth, particle diameter, topography and structural strength. Measured values of attrition rate decrease with time to a steady state value, which, under normal FBC operating conditions, is attained after a time in the bed of 6 - 10 hours. The elutriation model considers the effect of fines, generated by attrition, on the carry-over of coarse particles from the bed. The overall process model confirms that choice of sulphation kinetics exerts the greatest influence on attainable sulphur capture,. although bed fluid dynamics, sorbent attrition and feed size distribution all play a role. The model is substantiated by extensive data from the performance of three dissimilar sorbents in a 10 MWth FBC. The contribution of sorbent attrition to the solids loading of downstream gas cleaning equipment is highlighted.
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Nahar, Noor Un. "Ultrafine aerosol generation and use as a sorbent for SO₂ and NOx in coal combustion." Ohio : Ohio University, 1992. http://www.ohiolink.edu/etd/view.cgi?ohiou1172863696.
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Lively, Ryan P. "Hollow fiber sorbents for post-combustion CO₂ capture." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/43758.
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As concerns mount about the rise in atmospheric CO₂ concentrations, many different routes to reduce CO₂ emissions have been proposed. Of these, post-combustion CO₂ capture from coal-fired power stations is often the most controversial, as the CO₂ capture system will remove generating capacity from the grid whereas many of the other solutions involve increasing the generating capacity of the grid with low CO₂-emission plants. Despite this, coal-fired power stations represent a major point source for CO₂ emissions, and if a consensus is reached on the need to reduce CO₂ emissions, a low-cost method for capturing and storing the CO₂ released by these power plants needs to be developed. The overarching goal of this research is to design and develop a novel hollow fiber sorbent system for post-combustion CO₂ capture.
To achieve this goal, three objectives were developed to guide this research: i) develop a conceptual framework for hollow fiber sorbents that focuses on the energetic requirements of the system, ii) demonstrate that hollow fiber sorbents can be created, and a defect-free lumen layer can be made, iii) perform proof-of-concept CO₂ sorption experiments to confirm the validity of this approach to CO₂ capture. Each of these objectives is addressed in the body of this dissertation.
Work on the first objective showed that fiber sorbents can combine the energetic advantages of a physi-/chemi-sorption process utilizing a solid sorbent while mitigating the process deficiencies associated with using solid sorbents in a typical packed bed. All CO₂ capture technologies--including fiber sorbents--were shown to be highly parasitic to a host power plant in the absence of effective heat integration. Fiber sorbents have the unique advantage that heat integration is enabled most effectively by the hollow fiber morphology: the CO₂-sorbing fibers can behave as "adsorbing heat exchangers."
A dry-jet, wet-quench based hollow fiber spinning process was utilized to spin fibers that were 75wt% solid sorbent (zeolite 13X) and 25wt% support polymer (cellulose acetate). The spinning process was consistent and repeatable, allowing for production of large quantities of fibers. The fibers were successfully post-treated with an emulsion-based polymer (polyvinylidene chloride) to create a defect-free lumen side coating that was an excellent barrier to both water and gas permeation. A film study was conducted to elucidate the dominant factors in the formation of a defect-free film, and these factors were used for the creation of defect-free lumen layers. The work discussed in this thesis shows that the second objective of this work was definitively achieved.
For the third objective, sorption experiments conducted on the fiber sorbents indicated that the fiber sorbents CO₂ uptake is simply a weighted average of the support material CO₂ uptake and the solid sorbent uptake. Furthermore, kinetic experiments indicate that CO₂ access to the sorbents is not occluded noticeably by the polymer matrix. Using the fiber sorbents in a simulated rapid thermal swing adsorption cycle provided evidence for the fiber sorbents ability to capture the sorption enthalpy released by the CO₂-13X interaction. Finally, a slightly more-pure CO₂ product was able to be generated from the fiber sorbents via a thermal swing/inert purge process.
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Levickaitė, Giedrė. "Sorbentų naudojimo paviršinėms nuotekoms valyti tyrimai ir analizė." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110620_141622-97641.
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Didžiausiais paviršinių nuotekų teršalais laikomi naftos produktai ir skendinčiosios medžiagos. Pastarąsias galima nesunkiai pašalinti taikant tradicinius paviršinių nuotekų valymo metodus, tokius kaip nusodinimas, o naftos produktų šalinimui reikalingas antrinis nuotekų valymas. Vienas efektyviausių NP šalinimo iš nuotekų būdas yra filtravimas pro sorbuojančiosios medžiagos filtrą. Nors šiuo būdu valant nuotekas galima pasiekti didelio teršalų šalinimo efektyvumo, praktiškai dažnai susiduriama su problema, kai į eksploatuojamuosius valymo įrenginius nuotekos atiteka dideliais greičiais ir teršalai nėra iki galo pašalinami. Todėl šiame darbe buvo atliktas trijų skirtingų sintetinių sorbentų („Fibroil, „Duck“, „Reo-dry“) efektyvumo šalinti iš paviršinių nuotekų naftos produktus ekstremaliomis sąlygomis (esant dideliems greičiams) eksperimentinis tyrimas. Atlikus bandymus su dirbtinėmis ir realiomis paviršinėmis nuotekomis laboratoriniame stende, nustatyta, kad visų trijų sorbentų efektyvumas šalinti NP yra panašus ir skendinčiosios medžiagos bei nuotekų drumstumas neturi įtakos NP šalinimo efektyvumui. Tačiau „Fibroil“ sorbentą naudojant kaip filtro užpildą, 30 m/h greitį galima išlaikyti gerokai ilgiau nei su sorbentais „Duck“ ir „Reo-dry“ ir šį sorbentą naudoti ekonomiškiausia.
Darbą sudaro 8 dalys: įvadas, darbo aktualumo aprašymas, literatūros apžvalga, tiriamojo darbo metodikos aprašymas, eksperimeto rezultatai, rekomendacijos ir išvados bei literatūros sąrašas.
Darbo... [toliau žr. visą tekstą]Suspended solids and oil products are considered as the most important pollutants in the storm water. As suspended solids can be easily retained from storm water by simple sedimentation, for oil products it is usually needed to have a secondary treatment: filtration through sorbents media. Although storm water filtration through a sorbent filter gives high treatment efficiency, it is usually impossible to ensure the right speed of storm water coming to the treatment facilities (it is usually too high to ensure an efficient sorption). For this reason the research and analysis of three different synthetic sorbents („Fibroil“, „Duck“, „Reo-dry“) were performed with artificial and real storm water in the laboratory under extreme conditions (filtration speed 30 m/h). According to the results of the experiment, all three sorbents have similar treatment efficiency and suspended solids and turbidity has no impact on oil products removal efficiency. But it is more efficient to use “Fibroil” and it is suitable for filtration under 30 m/h speed much longer than sorbents “Duck” and “Reo-dry”. Structure: introduction, relevance, methodology, results of the experiment, recomedations conclusions and references. Thesis consist of: 55 p. text without appendixes, 21 pictures, 8 tables, 39 bibliographical entries.
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Hanna, J. A. "Industrial wastewater treatment using dolomite and dolomitic sorbents." Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431602.
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Meyer, Christoph. "Polymer-based chromatographic sorbents synthesis, characterization, and application /." [S.l. : s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11947869.
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Hnatajková, Eva. "Vliv sorbentů na retenční čáru kontaminované nivní půdy." Master's thesis, Česká zemědělská univerzita v Praze, 2017. http://www.nusl.cz/ntk/nusl-262766.
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The thesis deals with the influence of sorbents on the retention curve of the contaminated alluvial soil (fluvisol). The retention curves of soil without sorbents (reference soil) are compared with the soils enriched by the following sorbents. Biochar (BC), amorphous manganese oxide (AMO) and combination of (AMO + BC). Soils sample were collected is specific uncultivated area in the valley of Litavka river (located in the central part of the Czech republic).
Two different types of samples were used for measurement of retention curves. First type of the samples were collected from the column experiments and second type were the samples collected in the field. All samples were extracted using in Kopecky rings (100 cm3). The measurement of the retention curves was performed by a direct method in the laboratory. For laboratory determination of the retention curves classical set of instruments were used (sandbox, sand-kaolin box and pressure apparatuses). The measured data were fitted using van Genuchten. Values compared are the bulk density, parameters of van Genuchten model (Thétas, ThétaR, Alfa, n), and values pF (0; 1.0; 2.0; 2.7; 3.0; 3.7; 4.18). The comparison of retention curves of differently treated soil was based on the average, standard deviation and the difference and ratio of the avarages.
According to presented findings sorbents affected shapes of the retention curves. Especially biochar influence water content for high pF values. We confirmed the hypothesis according to VERHEIJEN et al. (2010), that biochar tincrase the total retention of soil water, but does not increase the amoust of water avaible plants.
The influence of AMO on retention curve was negligible. Therefore sorbent AMO has a small influence on change of water retention in the tested soil. The effect of combined sorbent (AMO + BC) on the retention more significant than effect of using AMO sorbent only. This combination of sorbents affects the water retention depending on applied pF.
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Hellman, Oskar. "Synthesis of framework porous sorbents using sustainable precursors." Thesis, Uppsala universitet, Nanoteknologi och funktionella material, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-445896.
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Metal organic frameworks (MOFs) is a quite recently discovered porous material group which shows potential in many different areas. One of these areas is carbon capture; the framework structure of the porous materials allows gas molecules to adsorb to the surface of the pores. MOFs are conventionally synthesised at high temperatures and with hazardous solvents. The goal of this projectwas to synthesise highly porous MOFs at room temperature with water as the main solvent, using environmentally friendly and non-hazardous precursors. As well as the room temperature synthesis, conventional synthesis methods were used with the same precursors as comparison. The materials were characterised with X-ray diffraction, thermogravimetrical methods and IR-spectroscopy. To assess the porosity of the materials, gas adsorption evaluation was performed with CO2, N2, SF6, and CH4 at 20⁰C. In the end, three novel porous magnesium-based materials and one zirconium-based material were successfully synthesised. One of the magnesium-based materials showed a moderately high CO2 adsorption (2.38mmol/g), and could be synthesised at room temperature. The zirconium-based material showed a remarkably high selectivity (17.7) for SF6 over N2 and a high surface area (550m2/g)
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Ritt, Cody. "Assessment of Molecularly Imprinted Polymers as Phosphate Sorbents." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28417.
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Wastewater effluents and agricultural runoff are major sources of phosphorus overloading in surface waters. Phosphorus overloading ignites eutrophication, which devastates aquatic ecosystems. On the other hand, phosphorus, which is currently produced from phosphate rock, is a critical component of fertilizer mixes. However, the world is predicted to face a shortage of phosphate supply beyond 2033 due to unsustainable mining. This research aims to develop a polymeric sorbent that recovers low-concentration phosphorus for eutrophication prevention and fertilizer reuse. Available polymer-based products have underwhelmed expectations by having poor selectivity or lacking appropriate biodegradation rates. This research identified molecularly imprinted polymers (MIPs) as possible sorbents for overcoming the deficiencies of reported technologies. Screening of several MIPs resulted in one potentially feasible MIP for phosphate sorption. Further studies showed a sorption capacity of ~28 mg PO43--P/g and partial phosphate-selectivity. Potential phosphate removal mechanisms were identified, providing foresight into MIPs? viability as phosphorus sorbents.North Dakota Department of Commerce (NDDoC Grant #: 14-11-J1-70); the National Institute of Food and Agriculture (NIFA-USDA Grant #: 2015-607022-22996); North Dakota Water Resources Research Institute (NDWRRI)
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Mandal, Dilip Kumar. "Production of improved calcium-based sorbents for sulfur dioxide capture." Ohio : Ohio University, 1993. http://www.ohiolink.edu/etd/view.cgi?ohiou1181672278.
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Jones, Michael T. "The disposal of spilled oils and sorbent materials." Thesis, Springfield, Va. : : Available from National Technical Information Service, 2001. University of Florida, 2001. http://handle.dtic.mil/100.2/ADA393129.
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Knight, Andrew. "Sorbent attrition in fluidized carbon dioxide capture systems." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44989.
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As part of a collaborative Carbon Management Canada project, the extent and causes of attrition for three proposed carbon dioxide capture sorbents for fluidized power generation systems was investigated. The sorbents are crushed limestone, lime-based pellets containing calcium aluminate cement binder, and the same pellets with a mesoporous silica coating replacing the binder. The tested sorbents were provided by the University of British Columbia, the University of Ottawa/CANMET, and Laval University, respectively.
The attrition testing equipment was an air-jet apparatus based on the ASTM D5757 standard, with several modifications to improve testing capabilities. The experiments were conducted under varying attrition test periods, gas velocities, temperatures, humidities, and initial particle sizes. Following each test cycle, particle size distributions of the produced fines and remaining bed material were analysed, and scanning electron microscopy was utilized to provide additional insight on attrition mechanism. The strengths and weaknesses of the ASTM standard were evaluated, and a new attrition testing standard is proposed to improve operability and reduce the equipment size and material requirements.
The experimental results indicate that the cement-bound pellets attrit to the same extent or worse than crushed limestone, and are highly sensitive to humidity because of the hygroscopic cement and formation of calcium hydroxide. Calcination substantially increases the friability of the cement-bound pellets and limestone. Both materials approached complete degradation after 24 h during the 500°C tests. However, the silica coated pellets were found to have high attrition resistance in dry air at 500°C. After 24 hours of operation, compared to the coated sorbents, the lime mean diameter reduction and Air Jet Index were greater by factors of 2.4 and 3.4, respectively. The 1 μm thick and 5 μm thick-coating pellets experienced nearly the same mean reduction in diameter and production of fines, a key finding for future studies of the economic viability of the coating process.
The tested materials experienced significant fragmentation, resulting in deviations from fines production models from the literature. The experimental results also displayed large variance in fines production rates during replicate trials. A novel model for mean diameter reduction rate is proposed, based on particle momentum.
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Park, Illam. "Adsorption and sorbent particle dynamics in packed beds /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu148784688577678.
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Sultan, Dewan Saquib Ishanur. "The capture of CO₂ from process streams using solid sorbents." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708420.
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Karayilan, Dilek. "Removal Of Hydrogen Sulfide By Regenerable Metal Oxide Sorbents." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605046/index.pdf.
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ABSTRACT
REMOVAL OF HYDROGEN SULFIDE
BY REGENERABLE METAL OXIDE SORBENTS
Karayilan, Dilek
M.S., Department of Chemical Engineering
Supervisor : Prof. Dr. Timur Dogu
Co-Supervisor: Prof. Dr. GülSen Dogu June 2004, 166 pages High-temperature desulfurization of coal-derived fuel gases is an essential process in advanced power generation technologies. It may be accomplished by using metal oxide sorbents. Among the sorbents investigated CuO sorbent has received considerable attention. However, CuO in uncombined form is readily reduced to copper by the H2 and CO contained in fuel gases which lowers the desulfurization efficiency. To improve the performance of CuO-based sorbents, they have been combined with other metal oxides, forming metal oxide sorbents. Sulfidation experiments were carried out at 627 oC using a gas mixture composed of 1 % H2S and 10 % H2 in helium. Sorbent regeneration was carried out in the same reactor on sulfided samples at 700 oC using 6 % O2 in N2. Total flow rate of gas mixture was kept at 100 ml/min in most of the experiments. In this study, Cu-Mn-O, Cu-Mn-V-O and Cu-V-O sorbents were developed by using complexation method. Performance of prepared sorbents were investigated in a fixed-bed quartz microreactor over six sulfidation/regeneration cycles. During six cycles, sulfur retention capacity of Cu-Mn-O decreased slightly from 0.152 to 0.128 (g S)/(g of Sorbent) while some decrease from 0.110 to 0.054 (g S)/(g of Sorbent) was observed with Cu-Mn-V-O. Cu-V-O showed a very good performance in the first sulfidation and excessive thermal sintering in the first regeneration prevented further testing. Sulfur retention capacity of Cu-V-O was calculated as 0.123 (g S)/(g of Sorbent) at the end of the first sulfidation. In addition, SO2 formation in sulfidation experiments was observed only with Cu-V-O sorbent.
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Uberoi, Mohit. "High-temperature removal of metal vapors by solid sorbents." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185195.
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Emissions of metal vapor compounds during incineration and combustion is becoming an increasingly important problem. The kinetics and mechanism of high temperature removal of various metal vapors by solid sorbents has been investigated in this study. The kinetics experiments were performed in a high temperature microbalance reactor system under simulated flue gas atmosphere. Scanning electron microscopy, X-ray diffraction analysis, atomic absorption/emission spectrophotometry, Energy dispersive X-ray analysis, mercury porosimetry, and BET surface area analysis were used for characterization of the fresh and reacted sorbents. The results show that the process of metal vapor capture is not just physical condensation, but rather a complex combination of various chemical and physical processes. There are some similarities in the sorption process. For all the sorbents the rate of metal vapor sorption decreases with time and there is a final limit beyond which no more metal vapor gets captured. However, there are differences in the rate and reaction mechanism of metal vapor removal. Kaolinite and bauxite are suitable sorbents for lead and cadmium capture. The melting point of the lead aluminosilicate product formed after reaction of lead chloride with kaolinite and bauxite has a low melting point. Therefore, these sorbents are more suitable for downstream fixed bed removal of lead compounds. Removal of cadmium by bauxite occurs due to chemical reaction to form a cadmium aluminum silicate and a cadmium aluminate. Removal of cadmium by kaolinite occurs due to the formation of only the cadmium aluminosilicate. The final products of cadmium sorption have a higher water solubility as compared to that of the corresponding products for lead. Chlorine is not retained by the sorbents during the sorption process. Kaolinite, bauxite and emathlite are suitable sorbents for removal of alkali compounds. In adsorbing alkali chloride vapors, kaolinite and emathlite release all the chlorine back to the gas phase while bauxite retains some of the chlorine. Moreover, the products of reaction with emathlite have a melting point significantly lower than those for kaolinite and bauxite. At lower alkali concentrations, NaCl reacts irreversibly with kaolinite to form a sodium aluminosilicate product. When the local metal vapor concentration in the sorbent pores becomes higher than the saturation concentration for condensation, the metal vapor physically condenses in the sorbent pores and may subsequently react with the solid. The theoretical models developed were used to extract kinetic parameters from experimental data and for parametric studies. The kinetic data obtained can be used in design of practical metal removal systems.
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Piccoli, Robert Francis. "Spectroscopic and chromatographic characterization of chemically modified silica sorbents." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282849.
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The most commonly used chromatographic and solid phase extraction sorbents are silica-based. Usually trifunctional silanes are used to modify silica sorbents because they can form polymer networks that provide increased stability as compared to sorbents prepared with monofunctional silanes. Unfortunately, the reactions of trifunctional silanes with a silica surface, and with each other, are difficult to control and the resulting polymerized bonded phase is very complex. Although these sorbents have been used extensively for various applications, studies of bonded phase chemistry continue to this day. The importance of such studies lies in the fact that an understanding of chemically modified silica sorbents will lead to the development of better chromatographic and solid phase extraction methods. This study focuses on the influence of silica topography on the structure and surface coverage of bonded phases, as well as the differences between hydrocarbon and ion exchange bonded phases. Solid-state NMR spectra, recorded for alkyl sorbents, showed that the porosity of the base silica determined the surface coverages of the different bonded phases. Large silanes and siloxane oligomers were excluded from micropores, limiting their access to a significant fraction of the silica surface area. These conclusions were made after analyzing the spectra of endcapped sorbents, which contained peaks that represented polymer and surface bound endcapping reagent. These experiments were supplemented with normal and reversed phase chromatographic data that indicated that shorter alkyl silanes were not dispersed evenly on the heterogeneous silica surface, as opposed to octyl and octadecyl silanes. In addition, bonded phases that contained excessive vertical polymerization were found to exhibit non-uniform retention behavior. Spectroscopic characterization of anion exchange sorbents supported the hypothesis that ionic silanes affect the structure of a bonded phase. It was discovered that the post-modification of cation exchange precursor sorbents also produced bonded phases without vertical polymerization. The uniformity of both anion and cation exchange sorbents was confirmed by studying the effects of endcapping. However, it was shown that an octyl thioacetate phase hindered bond breakage during postmodification oxidation. The resulting octyl sulfonic acid sorbent was shown to exhibit increased selectivity for analytes with both hydrophobic and ionic character.
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Samari, Mohammad. "CO2 Capture from Dilute Sources via Lime-Based Sorbents." Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/30978.
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Direct capture of CO2 from ambient air is a developing technology, which is capable of removing CO2 directly from the atmosphere. Moreover, this technology is independent from sources of CO2 emissions. Hence, it can be set up at locations where pure stream of CO2 is needed such as in enhanced oil recovery.
In this research, the performance of pelletized and natural limestone for CO2 capture from air in a fixed bed is studied. To compare the performance of sorbents for air capture, the effects of particle type (natural limestone and pelletized limestone), particle size (250-425 µm and 425-600 µm), gas flowrate (0.5 L/min and 1 L/min), and relative humidity, on the breakthrough time, breakthrough shape, and the global reaction rate are examined. Moreover, carbonation decay of sorbents over series of capture and regeneration cycles is studied.
If the inlet stream (air) is humidified at 50% relative humidity, but the lime sorbents are not pre-hydrated, an axially non-uniform carbonated bed results. This phenomenon is due to the partial carbonation of sorbents at the first layers of the bed. While there is a competition between CO2 and water to react with CaO, partial carbonation reaction on the surface of the sorbents not only prevents further hydration, but also decreases the reaction rate at the surface. However, in comparison with a dry system where relative humidity was negligible and sorbents were not pre-hydrated, the observed carbonation conversion was higher. The best results were seen from experiments with pre-hydrated sorbents and humidified inlet stream.
The smaller sorbent particles had a better performance (sharper breakthrough curve and longer breakthrough time) due to their greater surface area. A gas-solid reaction model was fitted to the breakthrough curves. Since at the beginning of carbonation there is no resistance of the product layer, it can be assumed that the process is reaction controlled. While after formation of the product layer (CaCO3), it becomes diffusion controlled. Results from fitted data also confirmed these conclusions. Moreover, each of sorbent went through 9 cycles and after each cycle the carbonation conversion of the sorbents was measured by TGA and the surface area by BET.
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Zhang, Yong. "Models of high temperature desulfurization using zinc based sorbents." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3661.
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Thesis (M.S.)--West Virginia University, 2004.Title from document title page. Document formatted into pages; contains xiv, 74 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 69-71).
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Watson, Ruth. "Organoclays : preparation, characterisation and use as sorbents and catalysts." Thesis, Sheffield Hallam University, 1997. http://shura.shu.ac.uk/20504/.
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This thesis reports the interactions of (poly)cations with a variety of clay minerals and the application of the resultant organoclays as both sorbents and catalysts. The behaviour of organoclays containing tetramethylammonium cations (TMA[+]), is compared to the behaviour of organoclays containing polycations of the formula [(Me[2]NCH[2]CHOHCH[2])[n]][n+] (Magnafloc 206), which are shown to form two distinct types of organoclay. To investigate the interactions of the (poly)cations with clay surfaces, several dry powder analysis techniques have been employed including Kjeldahl nitrogen analysis, variable temperature x-ray diffraction and thermogravimetric analysis. The studies have shown that the (poly)cations reside between the clay layers and that the nature of the clay and the resident exchange cation have a significant effect on the amount adsorbed. It is also shown that the polycations have a higher affinity than tetramethylammonium cations for all the clay minerals investigated. Sorbents exchanged with various amounts of (poly)cation are investigated for their ability to adsorb benzene and rho-nitrophenol from water. The adsorption by polycation containing sorbents is reduced compared to TMA[+] containing sorbents and the latter is comparable with that reported in the literature. The adsorption site in such sorbents is the siloxane surface in the clay interlayers, as shown by the observation that the uptake of both benzene and / rho-nitrophenol by TMA[+] exchanged SAz-1, a high charge montmorillonite, was reduced compared to TMA[+] exchanged SWy-1, a low charge montmorillonite. In SAz-1 there is closer packing of adsorbed TMA[+] cations resulting in less siloxane surface area being available. Hydration of the TMA[+] cations also increases steric constraints. High polycation loadings prevent the clay layers from expanding and thus accessibility of rho-nitrophenol to the clay surface is reduced. Partition into the organic carbon content of the polymer occurs but uptake does not increase with organic carbon content as expected. Also, TMA[+] exchanged Westone-L was expected to behave similarly to TMA[+] exchanged SWy-1 as Westone-L and SWy-1 have very similar cation exchange capacities. However, it is shown that TMA[+] exchanged Westone-L behaves more like TMA[+] exchanged SAz-1 which has a much higher cation exchange capacity. A range of organoclays containing either tetraalkylammonium cations or polycations at differing exchange levels have been subjected to acid leaching at either 25 or 90°C. The activity of these acid-activated (poly)cation-exchanged clays for the conversion of alpha-pinene to camphene and limonene was determined and compared with those from clay samples (without (poly)cations), acid-treated in the same manner. The presence of the polycation had a more marked influence on the activity of samples derived from SAz-1 than for corresponding samples derived from SWy-2, which was attributed to the increased hydrophobicity of the polycation loaded clay. Comparable yields for SWy-2 in the absence and presence of polycation suggest that SWy-2 disperses well in the nonpolar alpha-pinene. Also, octadecyltrimethylammonium and dodecyltrimethylammonium exchanged clays were generally less active than TMA[+] exchanged clays which were comparable to the most active polymer containing catalysts. It has also been shown that the octahedral iron content of the clay affects its catalytic activity. Finally, a competitive adsorption method of catalyst preparation has been developed which may replace more conventional high temperature techniques.
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Moos, Martin. "Prekoncentrační techniky pro stanovení uranu s využitím modifikovaných sorbentů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233331.
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The work has been focused on the preconcentration techniques for determination of uranium on the modified sorbent, with the final use of ICP-OES and ICP-MS. First ICP-OES at a wavelength of 385.958 nm was used for determination of uranium. Parameters were optimized and the effect of mineral acids (HCl, HNO3), tensides (Septonex, Ajatin) and organic reagents like (4-(2-pyridylazo)resorcinol, ammonium pyrrolidinedithiocarbamate, 8-hydroxyquinoline-5-sulphonic acid and 1,2-dihydroxyanthraquinone-3-sulphonic acid) was observed. For ICP-MS an isotope 238U was chosen. As an internal standard 209Bi (200 ?g•l-1) was used. Modified silica gel was used (Silicagel tethered with C18, C8 alkyls and phenyl) and two types of Amberlite XAD 4 and XAD 16 for the preconcentration of uranium (VI). Commercially produced Amberlite was modified as follows: Drying at 100 °C (24 hours), milled, minced sorbent was selected and fractionated to particles size ranging from 0.32 to 0.63 ?m and finally activated in methanol. The deionised water and Septonex (5•10-3 mol•l-1) at pH 8 were used for Amberlite conditioning. The optimal sorption of uranium (VI) proceeded at pH 8 in the presence of 4-(2-pyridylazo)resorcinol or ammonium pyrrolidinedithiocarbamate with Amberlite XAD-16 moreover with 1,2-dihydroxyanthraquinone-3-sulphonic acid. All organic reagents have mass concentration five time larger than uranium . For the elution of uranium the mixture of 1 mol•l-1 HNO3 with acetone (ratio of 1:1) was used. Acetone was evaporated and the final analysis performed using ICP-OES. The preconcentration of uranium (VI) using Silicagel-C18 conditioning was performed with ethanol, deionised water and Zephyraminu (5•10-4 mol•l-1) at pH 8. For the Silica-C8 and Silicagel-Phenyl the same conditioning procedure without zephyramin was used. Silica-C18 had the highest sorption efficiency with 1,2-dihydroxyanthraquinone-3-sulphonic acid, Silicagel-C8 with ammonium pyrrolidinedithiocarbamate and Silicagel-Phenyl with 8-hydroxyquinoline-5-sulfonic acid, all organic reagents have mass concentration five time larger than uranium concentration. As an optimal elution mixture acetone and ethanol (ratio of 1:1) in the presence of 1 mol•l-1 HCl was evaluated. Acetone and ethanol was evaporated and the final analysis was performed using ICP-MS. Silicagel-C18 was evaluate as the most effective in the presence of zephyramin and 1,2-dihydroxyanthraquinone-3-sulphonic acid. Sorption was also tested in the presence of 20 ?g•l-1 microelements (Be, V, Co, Ni, Y, Pb, Th, Cd) and in the presence of a defined concentrations of K, Na, Ca, Mg, Al and Fe. Direct analysis of uranium was carried out on samples of water from the river Ploucnice and Turonian aquifers containing uranium, 3,5 and 19,3 ?g•l-1. Different type of water required preconcentration of uranium (VI) on Silica-C18 in the presence of 1,2-dihydroxyanthraquinone-3-sulphonic acid and zephyramin. The analysis results gave statistically satisfactory results, which were confirmed using standard addition of 20 ?g•l-1.
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Samineni, Keerthi. "Adsorption of Bisphenol S from Water Using Natural Sorbents." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton151256696989552.
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Sun, Ping. "CO₂ removal in power systems using calcium-based sorbents." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31164.
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Bench scale studies were carried out, focusing on the application of calcium-based sorbents in fossil-fuel-fired combustion and gasification systems, with conditions ranging from atmospheric to elevated pressures and at practical combustion and gasification temperatures. In the kinetic study of CaO carbonation, the reaction order changed abruptly from first- to zero-order when the CO₂ partial pressure exceeded the equilibrium value by more than ~10 kPa. A Langmuir mechanism successfully explained the experimental information, with the intermediate complex CaO•CO₂ postulated to saturate CaO sites immediately at high CO₂ partial pressure. The activation energies for rate constants were found to be 29 ± 4 kJ/mol and 24 ± 6 kJ/mol for Strassburg limestone and Arctic dolomite, respectively. A discrete-pore-size-distribution-based model was formulated, with the aid of which the kinetic study was extended to obtain diffusivities through the solid product layer formed during carbonation, with activation energies of 215 and 187 kJ/mol for the limestone and dolomite, respectively. Sorbent cyclic CO₂ removal ability was investigated based on pore size distribution measurements. Several important features observed from measurements could be predicted by a mechanistic model which included simultaneous sintering and calcination in the fixed bed. It was found that the decay in the reversibility of limestone capture/regeneration was insensitive to operating conditions; the achievable carbonation extent of each cycle depends on the <~220 nm pore volume that decreases monotonically during cycling. Co-capture of SO₂ and CO₂ was attempted at fluidized bed combustion temperatures. Parametric studies with Strassburg limestone and Arctic dolomite found that the presence of SO₂ impeded carbonation even at low concentrations of SO₂ relative to CO₂ concentrations. This finding is significant for the application of calcium-based sorbents in fluidized-bed combustors (FBCs), given the initial assumption that sulphur should not be problematic given the low sulfur/carbon ratio in fuels. The mechanism of the impeding effect of SO₂ was investigated for seven sorbents at both atmospheric and elevated pressures. It was found that direct sulphation becomes dominant after completion of an initial fast stage of carbonation, enveloping the sorbents and inhibiting further carbonation. Among the techniques tested, increasing the CO₂ partial pressure was found to be the most helpful way to improve sorbent reversibility. It was also shown that often-cycled sorbents can be reactivated and achieve improved reversibility by the use of low-temperature steam or liquid water. CO is not appropriate as an agent to cyclically regenerate CaO from CaSO₄ because of slow regeneration of CaSO₄. Among the inert dopants tested, only Al₂O₃ mixed with CaO at a 1:1 molar ratio, was able to achieve satisfactory CO₂ capture reversibility. As extensions of the applications of calcium-based sorbents, sequential SO₂ and CO₂ capture were investigated for fluidized bed combustion. Among the four options examined, the best was found to be to apply spent sorbent after cyclic CO₂ capture to remove SO₂ from atmospheric pressure combustors. A novel concept of co-capture of CO₂ and H₂S in a gasifier-based process was also investigated. Unlike the findings for co-capture of SO₂ and CO₂, no obvious impeding effect of H₂S was observed on cyclic CO₂ capture. Parametric studies indicated that it should be feasible to co-capture H₂S and CO₂. With CO₂ sorbents in a gasifier, one-step hydrogen production via gasification should be achievable.Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
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Abagnato, Samuele. "Analisi di impatto ambientale con metodologia LCA della cattura di CO2 con sorbenti: confronto tra calcium looping e sorbenti a base di Li4SiO4." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Negli ultimi decenni è emersa l'urgenza di limitare gli impatti ambientali dovuti all'emissione di gas serra, ed in particolare della CO2. Una delle tecniche individuate per contribuire a limitare queste emissioni nel settore della produzione elettrica è la Carbon Capture and Storage (CCS). La CO2 può essere rimossa dai fumi della combustione attraverso sorbenti solidi: in un primo reattore (il carbonator) i sorbenti solidi adsorbono la CO2 dalla corrente di fumi mentre in un secondo reattore (il calciner) i sorbenti vengono rigenerati. In questa tesi si confrontano due metodi di cattura con sorbenti: il calcium looping, in cui si impiega CaO, e l'uso di sorbenti a base di Li4SiO4. Il secondo metodo, emerso più di recente rispetto al primo, sembra presentare alcuni vantaggi nella fase di cattura della CO2, poiché la capacità sorbente di Li4SiO4 decade più lentamente rispetto a quella di CaO e poiché questi sorbenti innovativi necessitano di temperature minori per la rigenerazione. Il confronto dei due metodi di cattura della CO2 viene condotto tramite un'analisi LCA. Vengono individuati i flussi di materia ed energia necessari al funzionamento del sistema per catturare 1 tonnellata di CO2 da una centrale elettrica di taglia 500 MW e sulla base di queste quantità si ottengono gli impatti ambientali dovuti al funzionamento del sistema di cattura della CO2. Nell'analisi si modellano le filiere di produzione dei sorbenti, i trasporti, le forniture di elettricità e combustibile e lo smaltimento dei sorbenti esausti. Infine si analizzano i risultati dello studio LCA per individuare i processi più impattanti e si approntano modifiche procedurali, che vanno dall'allungamento della vita utile dei sorbenti al recupero dei materiali di scarto, per far sì che gli impatti ambientali del sistema di cattura siano minori.
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Fontenot, Sean, and Sean Fontenot. "Supramolecular Modification of Mesoscale Materials." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12356.
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The process of surface modification allows us to combine the structural advantages of materials with the chemical functionality of organic compounds. Attachment of functional organic molecules to surfaces of high surface area substrates yields materials having dense chemical functionality. Materials with meso- and nanoscale features are often used as support substrates because their small-scale features provide very high surface area. Mesoporous silica is one of the most chemically accessible mesoscale materials, and the well-established chemistries of its production and modification lead to controlled pore structure and rapid kinetics. Such materials have seen use as sorbents for environmental remediation of contaminated water. For this application, their high degree of functionality and high-affinity surface chemistries permit a relatively small amount of material to effectively treat a large volume of water.
The many advantages of these highly engineered materials come at a relatively high economic cost. The high-affinity chemical functionalities that provide these materials with unprecedented efficiencies also make them correspondingly more difficult to recycle. One-time utilization of these materials makes the cost-per-use high which consequently limits their economically viable applications. The goal of this work has been to explore surface chemistries that will allow high performance, regenerable or recyclable sorbent materials. Shifting from a single-use material to a regenerable platform in which the mesoscale supports are recycled may lower the environmental and economic costs of the material while retaining the advantageous properties of the meso- and nanostructured materials.
We chose to approach this goal by developing non-covalent, supramolecular surface modification techniques as alternatives to current surface modification techniques which, almost without exception, are based on covalent modification motifs. Non-covalent attachment of organic molecules to surfaces allows us to avoid the necessity of optimizing the attachment for each class of organic molecule as well as avoid protection and de-protection procedures necessary to attach delicate or reactive functional groups to surfaces. In this way, supramolecular modification processes reduce the cost of material research and development in addition to the costs of material production and use.
The process of surface modification allows us to combine the structural advantages of materials with the chemical functionality of organic compounds. Attachment of functional organic molecules to surfaces of high surface area substrates yields materials having dense chemical functionality. Materials with meso- and nanoscale features are often used as support substrates because their small-scale features provide very high surface area. Mesoporous silica is one of the most chemically accessible mesoscale materials, and the well-established chemistries of its production and modification lead to controlled pore structure and rapid kinetics. Such materials have seen use as sorbents for environmental remediation of contaminated water. For this application, their high degree of functionality and high-affinity surface chemistries permit a relatively small amount of material to effectively treat a large volume of water.
The many advantages of these highly engineered materials come at a relatively high economic cost. The high-affinity chemical functionalities that provide these materials with unprecedented efficiencies also make them correspondingly more difficult to recycle. One-time utilization of these materials makes the cost-per-use high which consequently limits their economically viable applications. The goal of this work has been to explore surface chemistries that will allow high performance, regenerable or recyclable sorbent materials. Shifting from a single-use material to a regenerable platform in which the mesoscale supports are recycled may lower the environmental and economic costs of the material while retaining the advantageous properties of the meso- and nanostructured materials.
We chose to approach this goal by developing non-covalent, supramolecular surface modification techniques as alternatives to current surface modification techniques which, almost without exception, are based on covalent modification motifs. Non-covalent attachment of organic molecules to surfaces allows us to avoid the necessity of optimizing the attachment for each class of organic molecule as well as avoid protection and de-protection procedures necessary to attach delicate or reactive functional groups to surfaces. In this way, supramolecular modification processes reduce the cost of material research and development in addition to the costs of material production and use.
This dissertation contains previously published and unpublished co-authored material.
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Davies, Neil Harvey. "Limestone as a desulphurising sorbent in power generating systems." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337999.
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Ding, Kaijie. "Arsenite removal from contaminated water by different sorbent materials." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-273970.
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Arsenic (As) contamination is a worldwide problem, and millions of people are suffering from it. There are two major inorganic forms of As in waters: arsenate(V) and arsenite(III), and adsorption to a sorbent material may be an efficient method to handle them. In this study, we focused on As(III), the more toxic form, which predominates under reducing conditions. The As(III) removal properties of four sorbent materials: hydrotalcite, Mg−Al layered double hydroxide, amorphous aluminium hydroxide and amorphous titanium oxide, are examined from the following viewpoints: As(III) adsorption, the effects of pH, the effects of adsorbent concentration, adsorption as a function of dissolved As(III), and the effect of co-existing anions (HCO3− and PO43−). The maximum adsorption of As(III) to HT (0.1 mmol As(III)/g adsorbent), Mg-Al LDH (0.1 mmol As(III)/g adsorbent), am-Al(OH)3 (0.22 mmol As(III)/g adsorbent), and am-TiO2 (0.21 mmol As(III)/g adsorbent) occurred at pH 7.5, 7, 7, 8, respectively. At this pH, approximately 20%, 62%, 35%, and 98.3%, respectively, of the added As(III) was adsorbed. When the As(III) to sorbent ratio was increased, the adsorption was instead around 7% to am-Al(OH)3 (2.2 mmol As(III)/g adsorbent), and 46.3% to am-TiO2 (2.1 mmol As(III)/g adsorbent). These figures show that am-TiO2is the most efficient sorbent for As(III) adsorption of the four materials tested, Mg-Al LDH is second best, while HT and am-Al(OH)3 are not suitable for As(III) removal. The adsorption of As(III) to Mg-Al LDH as a function of dissolved As(III) could be adequately described by a linear equation, suggesting that As(III) adsorption to Mg-Al LDH was governed by anion exchange. As a result, the co-existing anions (HCO3- and PO43-) showed a significant influence on As(III) adsorption to Mg-Al LDH. Considering the interfering effects of co-existing anions on am-TiO2, HCO3− did not influence As(III) adsorption, while PO43- caused a slight but clear competition effect. Overall, am-TiO2 would be the best choice of these four materials in contact with As-contaminated groundwater due to its superior As(III) removal properties and the limited competition from co-existing anions on As(III) adsorption.Alltför höga halter av arsenik (As) i vatten är ett världsomspännande problem som orsakar hälsoproblem för miljontals människor. Det finns två huvudsakliga oorganiska former av As i vatten: arsenat(V) och arsenit(III), och adsorption till ett material (s.k. ”sorbent”) kan vara eneffektiv metod för att avlägsna dem från vatten. I denna studie fokuserade vi på arsenit(III), den mer giftiga formen, vilken dominerar under reducerande förhållanden. Vi undersökte adsorptionsegenskaperna för arsenit(III) för fyra sorbentmaterial som kan vara tänkbara när det gäller arsenikrening av förorenade vatten: hydrotalkit, s.k. Mg-Al LDH (Mg-Al-skiktad dubbelhydroxid), am-Al(OH)3 (amorf aluminiumhydroxid), och am-TiO2 (amorf titandioxid). Dessa material undersöktes när det gäller följande: adsorption av arsenit(III) som funktion av pH,betydelsen av sorbentkoncentration, adsorption som funktion av löst arsenit(III) (”isoterm”), och konkurrens från samexisterande anjoner (HCO3− och PO43−). Den maximala adsorptionen av As (III) till HT (0,1 mmol As(III)/g sorbent), Mg-Al LDH (0,1 mmol As(III)/g sorbent), am-Al(OH)3 (0,22 mmol As(III)/g sorbent) och am-TiO2(0,21 mmol As(III)/g sorbent) inträffade vid pH 7,5, 7, 7, respektive 8. Vid dessa pH-värden adsorberades ungefär 20%, 62%, 35% respektive 98,3% tillsatt As(III). När kvoten mellan As(III) till sorbent ökades blev adsorptionen istället cirka 7% till am-Al(OH)3 (2,2 mmol As(III)/g sorbent) och 46,3% till am-Ti02(2,1mmol As(III)/g sorbent). Dock var adsorptionsmängden per viktsenhetsorbenthögre över hela pH-området. Dessa siffror visar att am-TiO2 är det mest effektiva av de fyra testade materialen för As(III)-adsorption, Mg-Al LDH det näst bästa, medan HT och am-Al(OH)3 är olämpliga för detta ändamål. Adsorptionen av As(III) till Mg-Al LDH som funktion av löst As(III) kunde beskrivas väl med en linjär ekvation, vilket antyder att adsorptionen av As(III) till Mg-Al LDH styrdes av anjonbyte. I konsekvens med detta hade de samexisterande anjonerna (HCO3- och PO43-) ett betydande inflytande på As(III)-adsorptionen till Mg-Al LDH. För am-TiO2 påverkade HCO3− inte As(III)-adsorptionen, medan PO43- orsakade en liten men tydlig konkurrenseffekt. Sammantaget är am-TiO2 det bästa valet av dessa fyra material i kontakt med As- kontaminerat grundvatten på grund av dess betydligt bättre förmåga att avskilja arsenit(III) och den förhållandevis blygsamma konkurrensen från andra anjoner.
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Xiong, Rentian. "Novel Inorganic Sorbent for High Temperature Carbon Dioxide Separation." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1057765916.
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Blamey, John. "Improved performance of CaO-based sorbent for CO₂ capture." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9650.
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Calcium looping is a CO2 capture technology that is currently being developed on a 1 MWth pilot-scale. It has advantages including the ability to reclaim high-grade heat, the use of a relatively inexpensive, abundant and benign sorbent, and the potential to de-carbonise both power generation and cement manufacture. It makes use of the reversible carbonation of CaO to remove CO2 from a flue gas and provide pure CO2 for compression and storage, in a cyclical process. One aspect that is disadvantageous is the deactivation of CaO-sorbent upon cycling through reactive sintering; it is enhancement of sorbent that is examined here. Periodically hydrating sorbent, which can enhance sorbent performance by increasing reactive porosity, has been investigated: • Hydration conversion decreases following cycles of carbonation and calcination and at higher hydration temperatures. The latter has important consequences for the ability to reclaim high-grade heat from and reduce thermal cycling during the hydration process; • Particle breakage can occur upon hydration, which could be problematic for fluidised processes. This is more significant at lower hydration temperatures and for more highly sintered sorbents; • Direct carbonation of hydrated sorbent, rather than following a dehydration step, results in increased mechanical stability and increased reactivity to CO2; • Carbonation extent has an approximately linear relationship with prior hydration extent for equivalent carbonation methods; • A shrinking core model has been developed to describe the rate of reaction upon hydration. This successfully describes most data, but deviations are observed under conditions where pore blockage is likely. Enhancement of the performance of natural sorbent through surface doping with potassium compounds has also been investigated. KCl was found to enhance longterm conversion in the fluidised bed, with two mechanisms proposed: • Reduced friability of limestone, through KCl melt formation; • Increased carbonation rates in the slow solid-state diffusion phase.
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Zeiger, Claudia [Verfasser], and H. [Akademischer Betreuer] Hölscher. "Biomimetics for Efficient Oil Water Separation: From Natural Oil Sorbents to Bioinspired Micro- and Nanostructured Polymeric Sorbents and Membranes / Claudia Zeiger ; Betreuer: H. Hölscher." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/116254094X/34.
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Bhandari, Dhaval Ajit. "Hollow fiber sorbents for the desulfurization of pipeline natural gas." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/42838.
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Pipeline natural gas is the primary fuel of choice for distributed fuel cell-based applications. The concentration of sulfur in odorized natural gas is about 30 ppm, with acceptable levels being <1 ppm for catalyst stability in such applications. Packed bed technology for desulfurization suffers from several disadvantages including high pressure drop and slow regeneration rates that require large unit sizes.
We describe a novel Rapid Temperature Swing Adsorption (RTSA) system utilizing hollow fibers with polymer 'binder', impregnated with high loadings of sulfur selective sorbent 'fillers'. Steam and cooling water can be utilized to thermally swing the sorbent during the regeneration cycles. An impermeable, thin polymer barrier layer on the outside of fiber sorbents allows only thermal interactions with the regeneration media, thereby promoting consistent sorption capacity over repeated cycles. A simplified flow pattern minimizes pressure drop, porous core morphology maximizes sorption efficiencies, while small fiber dimensions allows for rapid thermal cycles.
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Godongwana, Ziboneni Governor. "Highly selective mesoporous sorbents for mercury removal from industrial wastewater." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8398_1320306023.
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The results of this study show that novel mesoporous carbons were obtained as inverse replica of SBA-15, HMS and MCM-41 silica templates, with a large pore diameter (2-4 nm), a BET surface area of 1867, 874 and 910 m2g â1 respectively for CA_SBA-15_LPG_105, CA_HMS_LPG_80 and CA_MCM- 41_LPG_80 with bimodal pore size distribution (PSD) in the mesopores range. The results obtained show that mesoporous carbon with graphitic structures can be synthesized via the LPG route.
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Boland, Diane Marie. "Characterization of the interactions on anion-exchange modified silica sorbents." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279905.
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Understanding the interactions at the modified silica interface used as a stationary phase in various chromatographic techniques is of great importance in elucidating the mechanism of solute retention. Investigating the factors that control the selectivity and efficiency for retention of a solute is also important as it can lead to the manipulation of the interfacial properties to give improved separations. In this research, solid phase extraction was used to obtain information about silica based anion-exchange stationary phases and their interaction with acidic analytes. Solid Phase Extraction (SPE) experiments using strong anion-exchange sorbents containing a fixed positive charge illustrated the importance of the counter-ion present at the surface. From these studies, it was determined that different counter-anions have different affinities for the ion-exchange site. Lower selectivity counter-anions (i.e. acetate) are more easily displaced from the sorbent by acidic analytes than a higher selectivity counter-anion (i.e. citrate). The general trend amongst counter-ions beginning with the counter-ion with the greatest affinity for the ion-exchange site is shown here: citrate > maleate > sulfate > formate > phosphate > chloride > hydroxide > nitrate > propionate > acetate. Overall, selectivity was not only determined to be a function of ionic interactions, but was also found to be a function of the extent of hydration of both the counter-ion and the surface. Weak anion-exchange sorbents consisting of primary and secondary amines were also investigated. In order for weak sites to contain ion-exchange sites, the pH needs to be selected so that the surface is ionized. Due to the pH dependence of weak anion exchangers, studies were undertaken to determine the effect that pH has on the extraction of acidic analytes. It was determined that the pH at the surface is not necessarily that of the bulk solution. It was also concluded that ionic, hydrophobic, strong dipole, and charge-induced dipole interactions contribute to the extraction of acidic compounds. SPE was also applied to the isolation and purification of acidic compounds. With a better understanding of the surface/solvent environment, a generic approach was developed for the extraction of toxicologically relevant compounds from biological matrices. By understanding the influence of pH, counter-anion, and degree of hydrophobic character of both analyte and surface, an enhancement in extraction efficiency and selectivity was achieved.
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Davis, Sheldon Brant. "Interactions between semi-volatile toxic metals and sorbents in combustors." Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/284079.
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The emission of semi-volatile toxic metals from boilers and incinerators is a major concern. One potential method to control semi-volatile metal emissions is high temperature sorbent injection. In this work, binary combinations of two toxic metals and three sorbents--kaolinite, hydrated lime, and a paper waste-derived sorbent (PWDS), were examined qualitatively and quantitatively. PWDS is a novel material produced from the waste sludge of the paper recycling process. An aerosol size-fractionation technique was developed to discriminate between metal vapor and metal that is either condensed on or reacted with particles in the furnace. A rapid-quench sampling system forces homogeneous nucleation to occur in the presence of other particles. Small nuclei generated from metal vapor are easily distinguished from metal reacted or condensed to larger particles. The aerosol size-fractionation technique was used to explore metal partitioning in the combustor. The longitudinal evolution of two mixtures, lead/cadmium, and cadmium/nickel, were examined. Based on this study, condensation and coagulation control aerosol processes in the furnace. Screening and parametric tests were performed to investigate the effect of injection temperature, sorbent/metal molar ratio and chlorine concentration on the capture of toxic metals by sorbents. In general, kaolinite and PWDS reacted rapidly with lead and achieved ∼100% lead sorption in a short time while cadmium was absorbed rapidly by lime only. The lead/lime reaction appeared to be slow compared to the other sorbents. In the presence of chlorine, the amount of lead captured by kaolinite and PWDS was significantly reduced. However, the small amount of lead absorbed by the lime seemed unaffected by chlorine. The reaction between lead and kaolinite was studied in detail. Lead capture increases with increasing sorbent feedrates and decreases with increasing chlorine concentration. The lead/kaolinite reaction appeared to be inhibited by higher temperatures. A simple global reaction model was proposed where the lead/kaolinite reaction product inhibits further reactions. Kinetic parameters were estimated from experimental results. The model was then modified to account for the effect of chlorine, the results of the model predict super-equilibrium concentrations of lead chloride vapor.
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Pandian, Babu Vinod Babu. "High-solids, mixed-matrix hollow fiber sorbents for CO₂ capture." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53435.
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Post-combustion carbon capture, wherein the CO2 produced as a result of coal combustion is trapped at the power plant exhaust, is seen as a bridging technology to reduce CO2 emissions and combat climate change. This capture process will however impose a parasitic load on the power plant and technologies need to be developed to minimize this energy penalty. This research focuses on a technology which uses solid sorbents fashioned into a hollow fiber form that allows water-moderated thermal cycling as a means of trapping CO2 from flue gas. While hollow fiber technology has intrinsic advantages over competing liquid amine and packed bed technologies, the materials used to fabricate hollow fibers and the fabrication process itself need to be optimized in order to result in competitive, robust hollow fiber sorbents. This dissertation focuses on the material selection process for each component of the hollow fiber platform and discusses ways to optimize the fiber and barrier layer formation. Different materials were evaluated to function as the solid sorbent, the matrix polymer and the barrier layer; and eventually their performance was measured against past work in this area.