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Couroyer, Charlotte G. M. "Attrition of alumina catalyst carrier beads." Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/843669/.
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Attrition of alumina catalyst carrier beads in reforming units causes operational problems and the loss of the catalyst particles due to the formation of fines and small fragments. This thesis addresses the characterisation and optimisation of the mechanical strength of these beads in collaboration with Institut Francais du Petrole (IFP) and Rhodia. A methodology was devised to test and improve the particle strength at various strain rates using both single particle and multiple particle tests by considering the mechanical stresses prevailing in industrial units. This methodology was tested with a commercial sample and then used to assess the strength of new samples for which the bead structure was modified by changing the filler concentration and type, the macroporosity, the drying regime and the surfactant concentration. A significant increase in the particle strength was achieved in comparison with the commercial samples. The mean crushing strength increased by a factor of about three and the extent of impact attrition was significantly decreased, e.g. by a factor of 30 for normal impacts at 20 m s-1. For single particle testing, a relationship between quasi-static and impact results was obtained when the impact breakage was compared with the percentage of weak particles obtained from the side crushing strength (SCS) test. This suggests that for this type of material the particle strength is not sensitive to the strain rate. Multiple particle tests confirmed the results obtained by single particle tests for two samples for which sufficient quantity of test material was available. In order to relate the extent of attrition in a particle assembly under compressive loading to the single particle properties, the BCS test was simulated by distinct element analysis using the TRUBAL code. Trends similar to the experimental work were obtained for the simulation of the attrition. However, the simulations tend to underestimate slightly the extent of attrition, which is highly dependent on the particle strength distribution and on the contact force distribution within the particle assembly. As a result of this work, the manufacture of the alumina catalyst carrier beads used in reforming units has been significantly improved.
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Miyazaki, Kazunari. "Studies on proton-conducting ceramic fuel cells for hydrogen-carrier utilization." Kyoto University, 2020. http://hdl.handle.net/2433/254526.
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Ferri, Giulia. "Identification and study of relevant descriptors of the solid during the synthesis of boehmite." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG064.
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Un support catalytique en alumine doit avoir des propriétés mécaniques et thermiques adéquates, et favoriser un transfert de masse et de chaleur approprié. Ces propriétés dépendent de la texture du support, qui est le résultat du procédé de fabrication. Cette thèse se concentre sur l’opération unitaire de peptisation et malaxage, qui implique la dispersion d’une poudre de boehmite dans une solution acide. Une base est ensuite ajoutée pour induire l’agglomération des particules de boehmite dispersées. Ce procédé, réalisé sous agitation, permet de contrôler la taille et la structure des agglomérats d’alumine qui constitueront le support solide du catalyseur. Ce travail vise à modéliser la structure solide de l’alumine en fonction des paramètres physico-chimiques qui dirigent l’agglomération colloïdale, en absence des forces hydrodynamiques. Afin d’étudier l’impact du pH, de la force ionique et de la concentration sur la cinétique de coagulation, trois techniques expérimentales sont utilisées : la diffusion dynamique de la lumière (DLS), la diffusion des rayons X aux petits angles (SAXS) et la microscopie électronique à transmission (STEM). Les résultats expérimentaux sont interprétés à travers l’équation du bilan de population, alimentée par un modèle de dynamique Brownienne. Les résultats du bilan de population sont ensuite utilisés pour paramétrer un modèle morphologique d’agglomération, afin de simuler de grands volumes de la structure poreuse du solide d’alumine. Le modèle morphologique fait partie des nouvelles contributions de cette thèse, et permet de calculer les propriétés texturales d’un grain de boehmiteAn alumina catalyst carrier must have adequate mechanical and thermal properties, and promote an appropriate mass and heat transfer. These properties depend on the carrier texture, which is the result of its manufacturing process. Our study focuses on the peptization and kneading process, which involves the dispersion of boehmite powder in an acid solution. A base is then added to induce the agglomeration of dispersed boehmite particles. This process, performed under mixing, enables to tune the size and structure of the boehmite agglomerates that will build the solid catalyst carrier. This work aims at modeling the alumina solid structure depending on the physical-chemical parameters that drive the colloidal agglomeration when no hydrodynamic forces are present. In order to study the impact of pH, ionic strength and concentration on the coagulation kinetics, three experimental techniques are used: Dynamic Light Scattering (DLS), Small Angle X-Ray Scattering (SAXS) and Scanning Transmission Electron Microscopy (STEM). The results of the experimental data are interpreted in terms of the population-balance equation, where the size-structure relationship is given by a Brownian dynamics model. The results of the population-balance model are then used as inputs for a morphological agglomeration model, to simulate large volumes of the porous structure of the real alumina solid. Such a model is one of the new contributions of this work, and enables to compute textural properties of a boehmite grain
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Векшин, Віталій Олександрович. "Очищення викидних газів абсорбції від оксидів нітрогену у виробництві нітратної кислоти." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22711.
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Дисертація на здобуття наукового ступеню кандидата технічних наук за спеціальністю 05.17.01 – Технологія неорганічних речовин. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016.
Дисертація присвячена розробці технології приготування каталізатору для промислових процесів селективного каталітичного відновлення (СКВ) оксидів нітрогену аміаком. На основі експериментальних досліджень визначені оптимальні параметри технології підготовки носія на основі оксиду титану для подальшого нанесення каталітично активної речовини. Встановлені оптимальні умови нанесення активної речовини – платини – з розчину H₂[PtCl₆] на поверхню носія, а саме: число просочень – 1, час просочення – 5 хв., концентрація розчину для просочення – 10%. Доведений позитивний вплив модифікаторів у процесі приготування каталізаторів методом просочення. Фізико-хімічними дослідженнями обґрунтовано застосування в процесі просочення мурашиної кислоти, в якості конкуруючого адсорбату, та доведені її відновлюючи властивості. Проведені експериментальні дослідження стосовно впливу промислових параметрів (температури, об’ємної швидкості) на активність отриманих каталізаторів. Показано кореляцію між розміром платинових кристалітів та тривалістю експлуатації каталізатора, що підпорядковується експоненціальній залежності і показує зменшення часу роботи каталізатора зі збільшенням розміру кристалітів при спіканні. Створено математичну модель процесу. Досліджені кінетичні характеристики процесу відновлення NOx аміаком, що дозволило визначити оптимальні умови процесу очищення: Т = 473 – 523 К, об'ємна швидкість 50 000 – 60 000 м³/год на каталізаторі, модифікованому мурашиною кислотою. Розроблено блочний каталізатор, реактор відновлення до нього та запропоновано принципову схему виробництва. Виконано техніко-економічне обґрунтування виробництва блочного каталізатору та проведена еколого-економічна оцінка його роботи. Показано, що розроблений каталізатор має гідравлічний опір в 12 разів нижче, ніж у промислового АВК-10. Еколого-економічні розрахунки показали, що зниження газового опору та зменшення у 2,5 рази екологічних витрат призведе до економії в розмірі 16 038 720 грн протягом 8 років, тобто протягом всього періоду роботи каталізатора.Thesis for a Candidate of Techical Sciences degree by speciality 05.17.01 – Technology of inorganic substances. – National technical university "Kharkov polytechnical institute", Kharkov, 2016. Thesis is devoted to the development of technology for preparing the catalyst for industrial processes of selective catalytic reduction (SCR) of nitrogen oxides with ammonia. Optimal technological parameters of preparation of carrier based of titanium oxide for following impregnation with catalytically active substance have been experimentally determined. Optimal parameters of application of the active substance – platinum – from solution of hexachloroplatinic acid on the surface of carrier have been found: the number of impregnations is 1, the impregnation time is 5 min, the concentration of the impregnation solution is 10%. The positive influence of modifiers – monobasic organic acids – on the catalyst preparation by impregnation has been proved. Application of formic acid in impregnation as a competing adsorbate and as a reducing agent has been substantiated by means of physico-chemical investigations. Experimental researches of the influence of industrial parameters (temperature, gas hourly space velocity) on the activity of obtained catalysts have been carried out. Correlation between the size of platinum crystallites and the time of catalyst operation has been determined. It obeys the exponential dependence and shows decrease in running time of the catalyst with increase in size of crystallites during sintering. Mathematical model of the SCR process has been developed. Kinetic investigations of the process of NOx reduction on obtained catalysts have been carried out. They allowed to determine the optimal conditions of purification, which are as follows: the maximum degree of reduction can be achieved at T = 473 – 523 K and the bulk gas flow 50 000 – 60 000 m³/h on a catalyst modified with formic acid. The designs of the block catalyst having cellular structure and industrial reactor for it have been suggested. It is shown that the gas flow resistance of the developed catalyst is 12 times lower than that of the ABK-10. Ecological-economic calculations and economic benefit estimation show that decrease of gas flow resistance and 2.5-fold ecological costs reduction will result in savings of 16,038,720 UAH during 8 years, i.e. during full period of catalyst operation.
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Векшин, Віталій Олександрович. "Очищення викидних газів абсорбції від оксидів нітрогену у виробництві нітратної кислоти." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22710.
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Дисертація на здобуття наукового ступеню кандидата технічних наук за спеціальністю 05.17.01 – Технологія неорганічних речовин. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016.
Дисертація присвячена розробці технології приготування каталізатору для промислових процесів селективного каталітичного відновлення (СКВ) оксидів нітрогену аміаком. На основі експериментальних досліджень визначені оптимальні параметри технології підготовки носія на основі оксиду титану для подальшого нанесення каталітично активної речовини. Встановлені оптимальні умови нанесення активної речовини – платини – з розчину H₂[PtCl₆] на поверхню носія, а саме: число просочень – 1, час просочення – 5 хв., концентрація розчину для просочення – 10%. Доведений позитивний вплив модифікаторів у процесі приготування каталізаторів методом просочення. Фізико-хімічними дослідженнями обґрунтовано застосування в процесі просочення мурашиної кислоти, в якості конкуруючого адсорбату, та доведені її відновлюючи властивості. Проведені експериментальні дослідження стосовно впливу промислових параметрів (температури, об’ємної швидкості) на активність отриманих каталізаторів. Показано кореляцію між розміром платинових кристалітів та тривалістю експлуатації каталізатора, що підпорядковується експоненціальній залежності і показує зменшення часу роботи каталізатора зі збільшенням розміру кристалітів при спіканні. Створено математичну модель процесу. Досліджені кінетичні характеристики процесу відновлення NOx аміаком, що дозволило визначити оптимальні умови процесу очищення: Т = 473 – 523 К, об'ємна швидкість 50 000 – 60 000 м³/год на каталізаторі, модифікованому мурашиною кислотою. Розроблено блочний каталізатор, реактор відновлення до нього та запропоновано принципову схему виробництва. Виконано техніко-економічне обґрунтування виробництва блочного каталізатору та проведена еколого-економічна оцінка його роботи. Показано, що розроблений каталізатор має гідравлічний опір в 12 разів нижче, ніж у промислового АВК-10. Еколого-економічні розрахунки показали, що зниження газового опору та зменшення у 2,5 рази екологічних витрат призведе до економії в розмірі 16 038 720 грн протягом 8 років, тобто протягом всього періоду роботи каталізатора.Thesis for a Candidate of Techical Sciences degree by speciality 05.17.01 – Technology of inorganic substances. – National technical university "Kharkov polytechnical institute", Kharkov, 2016. Thesis is devoted to the development of technology for preparing the catalyst for industrial processes of selective catalytic reduction (SCR) of nitrogen oxides with ammonia. Optimal technological parameters of preparation of carrier based of titanium oxide for following impregnation with catalytically active substance have been experimentally determined. Optimal parameters of application of the active substance – platinum – from solution of hexachloroplatinic acid on the surface of carrier have been found: the number of impregnations is 1, the impregnation time is 5 min, the concentration of the impregnation solution is 10%. The positive influence of modifiers – monobasic organic acids – on the catalyst preparation by impregnation has been proved. Application of formic acid in impregnation as a competing adsorbate and as a reducing agent has been substantiated by means of physico-chemical investigations. Experimental researches of the influence of industrial parameters (temperature, gas hourly space velocity) on the activity of obtained catalysts have been carried out. Correlation between the size of platinum crystallites and the time of catalyst operation has been determined. It obeys the exponential dependence and shows decrease in running time of the catalyst with increase in size of crystallites during sintering. Mathematical model of the SCR process has been developed. Kinetic investigations of the process of NOx reduction on obtained catalysts have been carried out. They allowed to determine the optimal conditions of purification, which are as follows: the maximum degree of reduction can be achieved at T = 473 – 523 K and the bulk gas flow 50 000 – 60 000 m³/h on a catalyst modified with formic acid. The designs of the block catalyst having cellular structure and industrial reactor for it have been suggested. It is shown that the gas flow resistance of the developed catalyst is 12 times lower than that of the ABK-10. Ecological-economic calculations and economic benefit estimation show that decrease of gas flow resistance and 2.5-fold ecological costs reduction will result in savings of 16,038,720 UAH during 8 years, i.e. during full period of catalyst operation.
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Jang, Yong-Jun. "Nanosized polymer carriers for metallocene catalysts in heterogeneous olefin polymerization." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976096374.
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Lindner-Lopez, Eduard. "Heterogenised palladium catalysts and magnetic carriers for fine chemicals production." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416028.
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Carriel, Schmitt Caroline [Verfasser]. "Catalytic upgrading of fast pyrolysis bio-oils applying nickel-based catalysts / Caroline Carriel Schmitt." Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1225401259/34.
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Gleichweit, Christoph Verfasser], Hans-Peter [Akademischer Betreuer] Steinrück, and Jörg [Akademischer Betreuer] [Libuda. "Dehydrogenation of Liquid Organic Hydrogen Carriers on Model Catalyst Surfaces / Christoph Gleichweit. Gutachter: Hans-Peter Steinrück ; Jörg Libuda." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2015. http://d-nb.info/1079718621/34.
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Zhou, Shanshan. "PORE-CONFINED CARRIERS AND BIOMOLECULES IN MESOPOROUS SILICA FOR BIOMIMETIC SEPARATION AND TARGETING." UKnowledge, 2017. http://uknowledge.uky.edu/cme_etds/78.
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Selectively permeable biological membranes composed of lipophilic barriers inspire the design of biomimetic carrier-mediated membranes for aqueous solute separation. This work imparts selective permeability to lipid-filled pores of silica thin film composite membranes using carrier molecules that reside in the lipophilic self-assemblies. The lipids confined inside the pores of silica are proven to be a more effective barrier than bilayers formed on the porous surface through vesicle fusion, which is critical for quantifying the function of an immobilized carrier. The ability of a lipophilic carrier embedded in the lipid bilayer to reversibly bind the target solute and transport it through the membrane is demonstrated. Through the functionalization of the silica surface with enzymes, enzymatic catalysis and biomimetic separations can be combined on this nanostructured composite platform. The successful development of biomimetic nanocomposite membrane can provide for efficient dilute aqueous solute upgrading or separations using engineered carrier/catalyst/support systems.
While the carrier-mediated biomimetic membranes hold great potential, fully understanding of the transport processes in composite synthetic membranes is essential for improve the membrane performance. Electrochemical impedance spectroscopy (EIS) technique is demonstrated to be a useful tool for characterizing the thin film pore accessibility. Furthermore, the effect of lipid bilayer preparation methods on the silica thin film (in the form of pore enveloping, pore filling) on ion transport is explored, as a lipid bilayer with high electrically insulation is essential for detecting activity of proteins or biomimetic carriers in the bilayer. This study provides insights for making better barriers on mesoporous support for carrier-mediated membrane separation process.
Porous silica nanoparticles (pSNPs) with pore sizes appropriate for biomolecule loading are potential for encapsulating dsRNA within the pores to achieve effective delivery of dsRNA to insects for RNA interference (RNAi). The mobility of dsRNA in the nanopores of the pSNPs is expected to have a functional effect on delivery of dsRNA to insects. The importance of pores to a mobile dsRNA network is demonstrated by the lack of measurable mobility for both lengths of RNA on nonporous materials. In addition, when the dsRNA could not penetrate the pores, dsRNA mobility is also not measurable at the surface of the particle. Thus, the pores seem to serve as a “sink” in providing a mobile network of dsRNA on the surface of the particle. This work successfully demonstrates the loading of RNA on functionalized pSNPs and identified factors that affects RNA loading and releasing, which provides basis for the delivery of RNA-loaded silica particles in vivo.
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Chung, Elena Yin-Yin. "Investigation of Chemical Looping Oxygen Carriers and Processes for Hydrocarbon Oxidation and Selective Alkane Oxidation to Chemicals." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469182957.
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Carrero, Marquez Carlos Alberto [Verfasser], and Reinhard [Akademischer Betreuer] Schomäcker. "Kinetic investigation for the oxidative dehydrogenation of propane (ODP) at tailored ternary (VO x) n-(TiO x) n /SBA15 catalysts / Carlos Alberto Carrero Marquez. Betreuer: Reinhard Schomäcker." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1028912897/34.
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O'Connor, Timothy F. III. "Synthesis and Dynamics of Photocatalytic Type-II ZnSe/CdS/Pt Metal-Semiconductor Heteronanostructures." Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1340038781.
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Freifrau, von Seckendorff-Gutend Jennie [Verfasser], Kai-Olaf Martin [Akademischer Betreuer] Hinrichsen, Kai-Olaf Martin [Gutachter] Hinrichsen, Dirk [Gutachter] Weuster-Botz, and Gregor D. [Gutachter] Wehinger. "Shape Matters - Experimental and Numerical Study on the Catalyst Carrier’s Geometry and the Utilization of 3d Printing herefor / Jennie Freifrau von Seckendorff-Gutend ; Gutachter: Kai-Olaf Martin Hinrichsen, Dirk Weuster-Botz, Gregor D. Wehinger ; Betreuer: Kai-Olaf Martin Hinrichsen." München : Universitätsbibliothek der TU München, 2021. http://d-nb.info/1230985190/34.
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Maigné, Alan. "Caractérisation et modélisation par microscopie électronique en transmission à balayage (STEM) et spectroscopie de perte d’énergie d’électrons (EELS) de « nanohorns » de carbone monofeuillet fonctionnalisés pour des applications pharmaceutiques Review of recent advances in spectrum imaging and its extension to reciprocal space Revealing the Secret of Water-Assisted Carbon Nanotube Synthesis by Microscopic Observation of the Interaction of Water on the Catalysts Role of Subsurface Diffusion and Ostwald Ripening in Catalyst Formation for Single-Walled Carbon Nanotube Forest Growth Effect of hole size on the incorporation of C60 molecules inside single-wall carbon nanohorns and their release Adsorption Phenomena of Tetracyano-p-quinodimethane on Single-Wall Carbon Nanohorns Carbon Nanohorns as Anticancer Drug Carriers Effect of Functional Groups at Hole Edges on Cisplatin Release from Inside Single-Wall Carbon Nanohorns Optimum Hole-Opening Condition for Cisplatin Incorporation in Single-Wall Carbon Nanohorns and Its Release Functionalization of Carbon Nanohorns with Azomethine Ylides: Towards Solubility Enhancement and Electron-Transfer Processes Aqueous carbon nanohorn–pyrene–porphyrin nanoensembles: Controlling charge-transfer interactions Photoinduced Electron Transfer on Aqueous Carbon Nanohorn–Pyrene– Tetrathiafulvalene Architectures Soluble Functionalized Carbon Nanohorns." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS600.
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La caractérisation et modélisation de « nanohorns » monofeuillets (SWNH) et de forêts de nanotubes par microscopie analytique sont présentées ainsi que leurs applications pour le traitement du cancer. Dans une première partie, nous introduirons les méthodes de microscopie et de spectroscopie utilisées dans nos expériences. Nous étudierons ensuite le processus de croissance de forêts de nanotubes de carbone monofeuillets (dans le contexte d’une collaboration avec l'AIST au Japon). Les SWNH, leur structure, propriétés de remplissage et de fonctionnarisation seront analysés et une nouvelle méthode sera présentée pour l'étude de la porosité de matériaux inorganique en EELS. Des calculs ab-initio seront aussi utilisés pour étudier l'effet des défauts dans les parois des SWNH sur les phénomènes d'oxydation et de remplissage des SWNH. Finalement, nous étudierons les possibles applications de SWNH dans le domaine pharmaceutique, et en particulier pour les traitements cancéreuxIn this manuscript, we will expose the characterization and modelling of Single Wall Nanohorns (SWNH) and Nanotube Forests by analytical microscopy and the functionalization of SWNH for drug delivery applications. Firstly, we will introduce the microscopy and spectroscopy methods used for our experiments. We will then study the growth process of Single Wall Carbon Nanotubes (SWCNT) forests (within the framework of a collaboration with AIST, Japan). SWCH, their structure, modifications and filling properties will be analysed in details. An original method will be presented to study the porosity of inorganic material with EELS. Ab initio calculation will also be used to explore the effect of the defects present in the SWNH wall on the oxidation and filling process. We will study the potentialities of Single Wall Carbon nanohorns as Drug Delivery Systems and particularly as anticancer drug carriers
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Lin, Chuan-Zong, and 林傳宗. "Dissolution Precipitation Graphite as carrier of platinum catalyst for PEMFC." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/22296817304873645823.
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碩士國立臺灣大學
材料科學與工程學研究所
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Proton exchange membrane fuel cell is a clean energy. After hydrogen oxidation and oxygen reduction, the final product is water. The catalysts and membrane play an important role in fuel cell system. The platinum and platinum- ruthenium was the most popular catalyst. And the support was usually carbon black. Carbon black had good conductivity and large specific surface area. The surface of carbon black is oxidized under the cathode environment of a PEFC. Thus, the platinum particles would be agglomerated. In this work, the DPG powders containing few CNTs(carbon nanotubes) and three dimension structure graphite were used as the support of catalyst in proton exchange membrane fuel cell. The CNTs(carbon nanotubes) and three dimension structure graphite might make the catalyst disperse well and the promotion of the electrochemical performance. TEM image of the Pt nanoparticles were obtained by using a JEM-2000FX operating at 200 kV. Exchange current was obtained by cyclic voltammetry method. Exchange current of catalyst supported on mixing powders containing 30 wt.% DPG are higher by 9% and 19%, respectively, than exchange current of catalyst supported on 100wt.% carbon black. The DPG powders containing few fullerenes and CNTs(carbon nanotubes) could be used as the support of catalyst in proton exchange membrane fuel cell.
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Rao, Sudershan T. "Effect of carbon-oxygen surface complexes on the surface and catalyst carrier properties of sugar charcoal." Thesis, 1991. http://localhost:8080/iit/handle/2074/3510.
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Wang, Wei Sheun, and 汪慰萱. "Evaluation of Zeolite L as Catalyst Carrier and Analysis of Reaction Mechanism for Dehydroisomerization of n-Butane." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/14998645658123932629.
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Shiau, Shich Chin, and 蕭旭欽. "Evaluation of γ-Al2O3 as Catalyst Carrier and Analysis of Reaction Mechanism for Dehydroisomerization of n-Butane." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/71101072222454118961.
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碩士東海大學
化學工程研究所
81
Isobutylene is raw material for many important petrochemicals , and it also reacts with methanol to form methyl-tertiary-butyl- ether(MTBE), which is an excellent gasoline blending material for cleaner auto exhaust. This researh study the feasibility of using γ-Al2O3 as carrier impregnated with metal to form bi- functional catalyst for dehydroisomerization of n-butane. Experimental data showed that reaction temperature around 823K offered best results. Reaction with (0.05% Pt + 0.5% Ga)/γ-Al2 O3 catalyst at 823K and space time of 0.3 s yielded 14% conversion of n-butane, and 70% and 16% selectivies of total butenes and isobutylene, respectively. This reaction system could be lumped as a network of three reactions, namely dehydrogenation, isomerization, and side reaction. Dehydrogenation reation had an intrinsic activation energy of 25 kJ/mol;Skeletal isomerization reaction had an intrinsic activation energyof 44 kJ/mol; Side reaction had an intrinsic activation energy of 135 kJ/mol.
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Lu, Po-Chang, and 盧柏璋. "Application of Taguchi Method in the Optimization of the Porous Ceramic Catalyst Carrier Fabricated by Replica Method." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/bef3q4.
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碩士國立臺北科技大學
資源工程研究所
106
Ammonia is a toxic substance commonly used in industry. If it is directly discharged into the atmosphere without being treated or directly inhaled by the human body, it will cause significant damage to the environment and human body. Reducing the concentration of ammonia emissions is often achieved through the "oxidation catalytic method." The composition of the catalyst can be divided into two parts: catalyst material and carrier. This study focuses on the synthesis of the catalyst carrier. Taguchi experimental design method was used to synthesis porous ceramics as a catalyst carrier material by replica method, and the effects of parameters such as ratio of ceramic slurry, sintering temperature, and sintering time on the compressive strength and porosity of the support material were investigated. In this study, kaolin and other additives were used to make the ceramic slurry, and the PU template was impregnated to coat the slurry on the template. The template was burned and sintered to form a carrier material after high temperature. Taguchi analysis showed that a PVA(aq) with a molecular weight of 77,500 was selected as a solvent to prepare a 50 wt.% kaolin solution, and 3 wt.% albite powder was additionally added as a flux. After the excess slurry was removed by extrusion-type de-slurry, sintering was performed. After holding temperature at 1150°C for 7 hours to form the sample, the secondary slurry penetrates into the sample through negative pressure to perform sintering. The best compressive strength can be obtained initially, reaching 1.74 MPa. Using a PVA with a molecular weight of 121000 as a solvent, 33 wt.% kaolin slurry was prepared, and 3 wt.% of glass powder was additionally added as a fluxing agent. After the excess slurry was removed by blowing, sintering was performed at 1100°C for 9 hours to obtain the best porosity, which is 93.07% Compared with commercially available honeycomb supports, although the compressive strength is not as good as commercially available honeycomb supports, their porosity is much higher than that of commercially available supports, and their mass is also much lighter than that of commercially available monomers. Catalytic properties are also inferior to commercial ones. The compressive strength of reticulated porous ceramics synthesized by the optimum level parameters in this study was 3.17 MPa, and the porosity was 52.38%. All of L18s used compounding ratios were able to successfully synthesize reticulated porous ceramic materials with basic mechanical properties. Compared with commercially available honeycomb supports, although their compressive strength is not as good as commercially available honeycomb supports, their porosity is higher than that of commercially available supports, their mass is also much lighter than that of commercially available supports. The catalytic activity of Ammonia gas conversion efficiency is also not inferior to the commercial support.
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Korzeniowska, Aleksandra. "Nanostrukturalne materiały porowate jako katalizatory oraz nośniki leków w medycynie i ochronie środowiska." Praca doktorska, 2019. https://ruj.uj.edu.pl/xmlui/handle/item/77303.
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CHEN, JIA-YIN, and 陳佳吟. "Application and synthesis of pyridine crown ether analogs phase transfer catalyst and magnesium ion transport crown ether carrier in liquid membrane." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/01722969741202099422.
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Hansen, Steven Paul. "Ion selectivity in carrier-mediated dialysis and electrodialysis." Thesis, 2012. http://hdl.handle.net/1828/3975.
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Membrane transport processes underlie many purification technologies. The efficiency of a membrane separation process depends upon material throughput (flux), and the degree to which the membrane discriminates amongst species in the feed stock (selectivity). In a supported liquid membrane, flux may be enhanced by carrier molecules, which act as catalysts of translocation. Carrier molecules also confer selectivity, via differential molecular recognition of the substances in the feed stock. The effect of electrical potential on the flux and selectivity of carrier-containing supported liquid membranes is not well documented. We elected to study the effect of electrical potential on supported liquid membranes containing valinomycin, a potassium ionophore, and a calixarene ester, a sodium ionophore. In these systems, the open circuit membrane potential could be made positive or negative by the choice of anion. With both of these carriers, we observed that selectivity for potassium or sodium salts was dependent on the open circuit membrane potential. To confirm that electrical potential was responsible for the observed selectivity variance, we applied a potential across the membrane using a potentiostat. The applied potential created conditions for carrier-mediated electrodialysis, where oxidation and reduction reactions on either side of the membrane act as the driving force for transmembrane flux of charged species. In chronoamperometry experiments, we found that selectivity for potassium or sodium ion was dependent on the applied electrical potential. Subject to some constraints, selectivity and flux could be controlled by the application of positive or negative electrical potentials. Linear sweep voltammetry experiments allowed for the rapid prediction of the potential that must be applied to achieve optimal selectivity. We also found that membrane potential measurements, as well as the magnitude of current that flows in chronoamperometry experiments, could be interpreted to predict Eisenman and Hofmeister sequences. These results are novel, and await a convincing theoretical justification. The results also suggest that a separation technology could be developed around the idea of modulating selectivity with electrical potential. In this regard, carrier-mediated electrodialysis may be suitable for the sequestration of toxic or radioactive heavy metals, and a large number of carrier molecules for metal ions are currently known. The technique may also be suitable for separating organic molecules, such as high-value chiral pharmaceuticals. Supported liquid membranes are a useful research tool, but industrial applications may require a more stable membrane architecture.Graduate
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Li, Yun-Ling, and 李芸菱. "The photocalytical removal of trichloroethylene in water by clay-carrier impregnated with metal catalysts." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/43357022155063493774.
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碩士國立屏東科技大學
環境工程與科學系
94
The chloride organic compounds have potential carcinogenic, tumor, and monster characteristics. Among these carcinogenic substances, trichloroethylene (TCE) is an artificial synthesis material. When it exposes to the atmosphere, it will influence the environment and health. In view of this, in this study, modifications of clay minerals are conducted to form clay catalysts and are illuminated with visible light in order to carry on photocatalysis to degrade the TCE. The main purpose is to discuss the possible mechanism and impact when clay catalysts are performing photocatalytical degradation with visible light. The main clay carriers include smectite clay and guan-shan series soil and the catalysts are sm-Ti, sm-Ag, sm-Zn, Ks-Ti, Ks-Ag, and Ks-Zn to perform the batch and fixed continuous experiment and find out the photocatalytic efficiency and mineralization with different catalysts. The study shows that the adding amount of 0.08 wt% and 0.1 wt% have the best degradation efficiency on TCE. When more quantity of catalysts is added, the easier it is for the shielding effect to take place. This is because the catalyst carrier possesses better adsorbability on TCE so that the total degradation rate on TCE involves the adsorption rate and net degradation rate. In the batch and fixed continuous experiment, the suspension catalysts can achieve the fine degradation and adsorption efficiency; while the total and net degradation rate of fixed continuous experiment decrease with the increase of the rate of utilization. It presumes that the decrease of the active sites and surface area of catalysts and the production of the kinds of ions and the change of pH about cement boards. Therefore, the degradation efficiency of suspension catalysts is better than that of fixed continuous experiment on TCE. In mineralization, the total and net mineralization rate is in decreasing trend with the catalysis time. It is assumed that during the degradation, intermediates are produced causing the reduce of energy and slow down of mineralization rate. In the identification of intermediates, the above-mentioned methods can be shown that the intermediates can be produced and the concentration has trend of increase with the experiment time and the times of experiment. The intermediates can reduce the degradation efficiency and mineralization of catalysts on TCE.
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Krasnokutskiy, E. V., B. B. Makhanov, V. E. Ved, M. I. Satayev, A. V. Ponomarenko, and A. A. Saipov. "Universal multi-functional secondary catalyst carriers for purification of gas emission of thermal power equipments." Thesis, 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/28164.
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Bhat, Imtiyaz Ahmad. "Design and Application of Self-Assembled Coordination Cages for Catalysis and as Drug Carrier." Thesis, 2018. https://etd.iisc.ac.in/handle/2005/5350.
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In summary the present thesis accounts for the design and synthesis of various coordination cages
formed through the self-assembly reaction of the newly designed pyridine and pyrimidine based
ligands with various 90° palladium (II) and platinum (II) metal acceptors
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劉翼綵. "Investigation on fuel properties of biodiesel produced through transesterification using heterogeneous catalyst carried by coal fly ash." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/25878060205345664348.
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Jang, Yong-Jun [Verfasser]. "Nanosized polymer carriers for metallocene catalysts in heterogeneous olefin polymerization / vorgelegt von Yong-Jun Jang." 2005. http://d-nb.info/976096374/34.
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Hsieh, Cheng-Yu, and 謝正裕. "Synthesis and Application of Larient-type Crown Ethers as Ion Transport Carriers and Phase Transfer Catalysts." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/38809071851401176556.
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碩士國立師範大學
化學學系
81
The carboxylate crown ethers (sym-hydroxydibenzo-16- crown-5, DB16C5OH and sym-dibenzo-16-crown-5-oxyacetic acid, DB16C5COOH) were synthesized to apply as ion transport carriers and play as phase transfer catalyst (PTC) in organic synthesis. In the study of Na+ ion transport with sym-DB16C5COOH ,it seems to indicate that the bigger counter anion and more hydrophobic anions of sodium salts exhibited better transport.Besides the solvation of the salts, the pH values of source solution and target solution showed some effect on Na+ ion transport. In addition ,crown ethers effect on the Na+ ion transport was investigated ,the Na+ ion transport ability of various crown ethers seems to decrease in the order : DB16C5COOH>B15C5COOH> DB16C5OH>B15C5,it shows that side chain functional group on crown ethers may influence the Na+ ion transport ability. Crown ethers were applied as phase transfer catalyst (PTC) in the Claisen condensation reaction between ethyl acetate and ethyl benzoate.It showed that DB16C5OH was quite a good catalyst in the reaction which can increase the yield of the product from 10% to 70% for only 6 hours. The effects of crown ethers on the yield of the product were in the order: DB16C5OH > B15C5 > DB18 C6 >Blank>DB16C5COOH. Effect of solvent and temperature on the catalytic Claisen condensation reaction were also investigated. The reaction in lower polar solvents seems to show higher yield . The temperature study on the catalytic reaction reveals that it has a optimum temperature at 40oC and with the order 40oC > 60oC > 25oC . This maybe attributed to high solubility of NaOEt, but less stability of Na+/crown ether complexes at higher temperature . Concentration effect of crown ethers and reactant were also studied and discussed. The best result was obtained with the ratio crown ether/ reactants = 1/1.
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Hsu, Li-Yeh, and 徐禮業. "Studies on Catalytic Reduction of NO with NH3 over Cu Catalysts Supported on Carbon and Other Carriers." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/34599992327805779636.
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博士國立成功大學
化學工程學系碩博士班
91
The most widely employed catalysts in the SCR process are made of metal oxides or zeolites, which have optimum reaction temperatures ranging within 270–430 °C. Under this circumstance, reheating would be needed to bring the flue gas to the desired temperature if the catalyst bed were to be situated after the electrostatic precipitator and desulurization plant. The operative coats of SCR using the present catalysts are very expensive. In this study, we went to develop the more chip, lower operation temperature, and high activity of catalysts to replace the present catalysts. We found that the redox properties of copper oxide could be changed by the nature of supports and influence the activity of catalysts. The copper oxide over activated carbon is easily reduced and there is a good catalytic activity for NO reduction below 250 ºC. In addition, there are no activity over activated carbon (PFC) without ash content for catalytic NO reduction with NH3. The CuO impregnated on PFC can clearly increase activity of catalysts. The activity increases with the impregnated amount of CuO. The existences of oxygen-containing functional groups and copper oxide over activated carbon will increase the activity for NO reduction with NH3. Compared with CuO over PFC, oxygen-containing functional groups has less activity. The activity of catalysts is influenced by the dispersion of copper oxide over PFC. However, the disactivated catalysts, made by the higher heat treatment, can be regenerated by 1N HNO3. For selective catalytic NO reduction with NH3, NO conversion is near 100% over PFC catalyst, impregnated 8 wt.% CuO, at 200 ºC. In the kinetic studies, Mars-van Krevelen model can fit the data of copper-supported catalysts. And the behavior of catalysts can be predicted at different reaction conditions by Mars-van Krevelen model.
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Ronovský, Michal. "Vysoce uspořádané tenké vrstvy oxidu kobaltu pro modelovou katalýzu." Master's thesis, 2020. http://www.nusl.cz/ntk/nusl-415468.
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Hydrogen processing is becoming increasingly important not only in the production of electricity but also during its accumulation. One of the energy storage options are liquid organic hydrogen carriers (LOHC). The main drawback of LOHC is the need for a large amount of thermal energy to release molecular hydrogen. We can bypass this issue using heterogeneous catalysis by transferring hydrogen from LOHC to acetone and using the produced 2-propanol (IPA) in the fuel cell. This innovative strategy of getting electri- cal energy from LOHC can be potentially energetically neutral. In this work, we studied highly ordered Co3O4(111) model catalysts for IPA oxidation in the as-prepared state and enhanced with platinum (Pt) nanoparticles. Catalysts were prepared by Physical Vapour Deposition (PVD) and further investigated by means of Low Energy Electron Diffrac- tion (LEED), X-ray Photoelectron Spectroscopy (XPS), Scanning Tunneling Microscopy (STM) and Temperature Programmed Desorption (TPD). The nucleation process of Pt on the as-prepared Co3O4(111) surface was studied by depositing low amounts 0.04 and 0.13 monolayer (ML) of Pt, that create clusters as small as 2 or 3 atoms with no need for a special nucleation site. We have identified the formation of Pt-induced defects in the atomically flat cobalt oxide...