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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Characterization and optimization of an extractor-type catalytic membrane reactor for meta-xylene isomerization over Pt-HZSM-5 catalyst

Daramola, Michael Olawale 12 1900 (has links)
Thesis (PhD (Process Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Future chemical production is faced with a challenge of limited material and energy resources. However, process intensification might play a significant role to alleviating this problem. Vision of process intensification through multifunctional reactors has stimulated research on membrane-based reactive separation processes, in which membrane separation and catalytic reaction occur simultaneously in one unit. These processes are rather attractive applications because they are potentially compact, less capital intensive, and have lower processing costs than traditional processes. Moreover, they often enhance the selectivity and yield of the target product. For about three decades, there has been a great evolution in p-Xylene production technology, with many equipment improvements being instituted in the industry. Typically, these improvements bring economic as well as processing advantages to the producers. Such developments are vital, as the capital costs for process equipment to produce and separate p-Xylene from xylene isomers, especially into high purity p-Xylene, still remain very high. However, with numerous advantages of membrane-based reactive separation processes compared to the conventional processes, the research focus has been channelled toward application of MFI-type zeolite membranes for in situ separation and isomerization of xylene in extractor-type catalytic membrane reactors. To contribute to this research line, this study has focused on characterization and optimization of an extractor-type catalytic membrane reactor (e-CMR) equipped with a nanocomposite MFI-alumina membrane as separation unit for m-Xylene isomerization over Pt-HZSM-5 catalyst. Nanocomposite MFI-alumina zeolite membranes (tubes and hollow fibres) used in this study were prepared via a so-called “hydrothermal pore-plugging synthesis technique” developed by Dalmon and his group more than a decade ago. In this concept, MFI material is grown by 'pore-plugging' direct hydrothermal synthesis in a porous matrix rather than forming thin films on top of the support. The advantages of this type of architecture over conventional film-like zeolite membranes include: (i) minimization of the effect of thermal expansion mismatch between the support and the zeolite, (ii) easy to scale-up, and (iii) easy module assembly, because the separative layer (zeolite crystals) are embedded within the pores of the ceramic support, reducing the effects of abrasion and thermal shocks. After membrane synthesis, the membrane quality and separation performance of these membranes were evaluated through single gas permeation (H2), binary gas separation (n-butane/H2) and ternary vapour mixture of xylene isomers using the vapour permeation (VP) method with p-Xylene as the target product. After evaluating the xylene isomer separation performance of the membranes, the membranes were used in extractor-type catalytic membrane reactors to carry out m-Xylene isomerization over Pt-HZSM-5 catalyst with p-Xylene as the target product. This dissertation has shown that nanocomposite MFI-alumina membrane tubes and hollow fibre membranes were selective to p-Xylene from xylene isomers. The dissertation also reports for the first time in open literature the excellent xylene separation performance of nanocomposite MFI-alumina membrane tubes at higher xylene loading (or vapour pressure). Unlike their film-like counterparts, the membranes still maintain increased selectivity to p- Xylene at higher xylene vapour pressures without showing a drastic decrease in selectivity. This outstanding property makes it a promising choice for pervaporation applications where concentration profile is usually a major problem at higher loading of xylene. With the use of nanocomposite MFI-alumina hollow fibre membranes, this research has demonstrated that membrane configuration and effective membrane wall thickness play a prominent role in enhancing cross membrane flux. Results presented in the study show, for the first time in open literature, that nanocomposite MFI-alumina hollow fibre membrane could enhance p-Xylene fluxes during the separation of ternary vapour mixture of xylene due to the smaller effective wall thickness of the membrane (membrane thickness <1 μm) when compared to conventional randomly oriented MFI zeolite films (membrane thickness >3 μm). During xylene isomers separation with nanocomposite hollow fibre membrane, about 30% increase in p-Xylene flux was obtained compared to the membrane tubes, operated under the same conditions. Additionally, hollow fibres offer the added advantage of membrane surfaceto- volume ratios as high as 3000 m2/m3 compared to conventional membrane tubes. Using this type of system could be instrumental in reducing both the size and cost of permeating modules for future xylene separation processes. However, obtaining high quality nanocomposite MFI-alumina membrane fibres is subject to the availability of high quality fibre supports. Regarding the application of nanocomposite MFI-alumina membrane tubes as extractor-type catalytic membrane reactors (referred to as extractor-type zeolite catalytic membrane reactor (e-ZCMR) in this study) for m-Xylene isomerization over Pt-HZSM-5, the results presented in this study further substantiate and confirm the potentials of e-ZCMRs over conventional fixed-bed reactors (FBRs). In the combined mode (products in the permeate plus products in the retentate), the e-ZCMR displayed 16-18% increase in p-Xylene yield compared to an equivalent fixed-bed reactor operated at the same operating conditions. On the basis of the high p-Xylene-to-o-Xylene (p/o) and p-Xylene-to-m-Xylene (p/m) separation factors offered by the membranes, p-Xylene compositions in the permeate-only mode (products in the permeate stream) in the range 95%-100% were obtained in the e-ZCMR. When a defect-free nanocomposite MFI-alumina membrane tube with p-Xylene-too- Xylene (p/o) separation factor >400 was used, ultra pure p-Xylene with p-Xylene purity approaching 100% in the permeate-only mode was obtained. Moreover, the e-ZCMR displayed 100% para-selectivity in the permeate-only mode throughout the temperatures tested. This is not possible with conventional film-like MFI-type zeolite membranes. Therefore, the application of nanocomposite MFI-alumina membranes in extractor-type catalytic membrane reactors could catalyse the development of energy-efficient membrane-based process for the production of high purity p-Xylene. Furthermore, in this dissertation, a report on modelling and sensitivity analysis of an e-ZCMR equipped with a nanocomposite MFI-alumina membrane tube as separation unit for m-Xylene isomerization over Pt-HZSM-5 catalyst is presented. The model output is in fair agreement with the experimental results with percentage errors (absolute) of 17%, 29%, 0.05% and 19.5% for p-Xylene yield in combined mode, p-Xylene selectivity in combined mode, p-Xylene selectivity in permeate-only mode and m-Xylene conversion, respectively. Therefore, the model is adequate to explain the behaviour of e-ZCMR during m-Xylene isomerization over Pt-HZSM-5 catalyst. The model is also adaptable to e-ZCMRs of different configurations such as hollow fibre MFI-alumina membrane-based e-ZCMRs. To gain more insight into the behaviour of the model to small changes in certain design parameters, sensitivity analysis was performed on the model. As expected, the sensitivity analysis revealed that intrinsic property of membrane (porosity, tortuosity), membrane effective thickness and reactor size (indicated with reactor internal diameter) play a significant role on the performance of e-ZCMR during p-Xylene production from the mixed xylenes. MFI-alumina zeolite membranes with optimized parameters such as membrane porosity, membrane tortuosity, and membrane effective wall thickness might enhance transport of p-Xylene through the membrane and thus resulting in higher p-Xylene flux through the membrane. This eventually would translate into an increase in p-Xylene yield in permeate-only mode. As far as it could be ascertained, this is the first report in open literature on modelling study with sensitivity analysis of e-ZCMR equipped with nanocomposite MFI-alumina membrane tubes as separation unit for m-Xylene isomerization over Pt-HZSM- 5 catalyst. In addition, the results of this study have confirmed previous research efforts reported on the application of extractor-type catalytic membrane reactors, having MFI-type membranes as separation units, for p-Xylene production via m-Xylene isomerization over a suitable catalyst. Also, new ideas were developed, tested and proposed that now provide a solid basis for further scale-up and techno-economical studies. Such studies are necessary to evaluate the competitiveness of the technology with the traditional processes for the production of high purity p-Xylene from mixed xylene. In summary, the encouraging results, as documented in this dissertation and also communicated to researchers in the area of membrane-based reactive separation (in the form of four peer-reviewed international scientific publications and four conference proceedings), could provide a platform for developing a scaled-up membrane-based energy-efficient industrial process for producing high purity p-Xylene through isomerization. / AFRIKAANSE OPSOMMING: Die produksie van chemiese stowwe word belemmer deur die uitdaging van beperkte materiaal- en energiebronne. Prosesuitbreiding kan egter ‘n noemenswaardige rol in die verligting van hierdie probleem speel. Die moontlike gebruik van multi-funksionele reaktore in prosesuitbreiding het navorsing in membraan-gebaseerde reaktiewe skeidingsprosesse (waar membraanskeiding en die katalitiese reaksie gelyktydig in ‘n enkele eenheid plaasvind) aangemoedig. Hierdie prosesse is aantreklik omdat hulle potensieel kompak en minder kapitaal-intensief is en ook teen laer koste as tradisionele prosesse bedryf kan word. Dit is ook dikwels die geval dat die multi-funksionele reaktor die selektiwiteit en opbrengs van die gewenste produk verhoog. In die afgelope drie dekades was daar ’n sterk verandering in die tegnologie wat gebruik word in die produksie van p-Xileen, met vele verbeterings aan nuwe toerusting wat in die nywerheid in bedryf gestel is. Hierdie verbeteringe hou gewoonlik ekonomiese-, sowel as bedryfsvoordele vir die produsente in. Ontwikkelings in hierdie veld is noodsaaklik aangesien die kapitale uitgawes vir die toerusting om p-Xileen, veral baie suiwer p-Xileen, van xileenpolimere te produseer en te skei, steeds baie hoog is. Met talle voordele gekoppel aan membraangebaseerde reaktiewe skeidingsprosesse in vergelyking met normale prosesse, is die navorsing egter gekanaliseer na die gebruik van MFI-tipe zeolietmembrane vir die in-situ skeiding en isomerisasie van xileen in ekstraksie-tipe katalitiese membraanreaktore. As bydrae tot hierdie navorsingsveld het hierdie studie op die karakterisering en optimering van ‘n ekstraksie-tipe katalitiese membraanreaktor (e-KMR), toegerus met ’n nanosaamgestelde MFI-alumina membraan as skeidingseenheid vir m-Xileen isomerisasie in die teenwoordigheid van ‘n Pt-HZSM-5 katalis, gefokus. Nanosaamgestelde MFI-alumina zeolietmembrane (buise en hol vesels) wat in hierdie studie gebruik is, is voorberei deur die sogenaamde “hidrotermiese porie-sperring sintese tegniek” wat meer as ‘n dekade gelede ontwikkel is deur Dalmon en sy groep. In hierdie tegniek word MFI-materiaal gekweek deur direkte hidrotermiese sintese in ‘n poreuse matriks, eerder as die vorming van dun films bo-op die ondersteuningsbasis. Die voordele van hierdie ontwerp bo dié van die konvensionele filmagtige zeolietmembrane sluit in: (i) minimering van die effek van termiese uitsetting op die gaping tussen die ondersteuningsbasis en die zeoliet, (ii) die gemak van opskalering, en (iii) die gemak waarmee die modules aanmekaar gesit kan word, omdat die skeidingslaag (zeolietkristalle) binne die porieë van die keramiek-ondersteuningsbasis geleë is, wat die effek van erodering en termiese skok verminder. Ná die membraansintese is die membraankwaliteit en skeidingsvermoë geevalueer deur enkel-gas-deurdringing (H2), binêre-gas-skeiding (n-butaan/H2), en ternêre dampmengsel van xileen-isomere deur die gebruik van die damp-deurdringingsmetode met p-Xileen as die teikenproduk. Hierdie tesis het gewys dat nanosaamgestelde MFI-alumina membraanbuise en hol vesel membrane selektief was ten opsigte van p-Xileen vanuit xileen-isomere. Die tesis doen ook, vir die eerste keer in die oop literatuur verslag, oor die uitstekende p-Xileen skeidingsvermoë van nanosaamgestelde MFI-alumina buise by hoër xileenladings (of dampdrukke). Anders as hulle filmagtige eweknieë het die membrane steeds hul verhoogde selektiwiteit vir p-Xileen by hoër dampdrukke behou, sonder ‘n merkbare verlaging in die selektiwiteit. Hierdie merkwaardige eienskap maak dit ‘n belowende keuse vir pervaporasie toepassings, waar die konsentrasieprofiel (as gevolg van hoër xileenladings) gewoonlik ’n noemenswaardige probleem is. Met die gebruik van nanosaamgestelde MFI-alumina membrane het hierdie navorsing gewys dat membraankonfigurasie en –wanddikte ‘n prominente rol speel in die verbetering van vloei oor die membraan. Resultate wat in die studie voorgelê word, wys, vir die eerste keer in oop literatuur, dat hol vesel nanosaamgestelde MFI-alumina membrane die deurvloei van p-Xileen kan verbeter gedurende die skeiding van ternêre dampmengsels van xileen, as gevolg van die kleiner effektiewe wanddikte van die membraan (<1 μm) wanneer dit vergelyk word met konvensionele kansgewys-geörienteerde MFI-zeoliet films met ‘n membraandikte van >3 μm. Tydens die skeiding van xileen-isomere met nanosaamgestelde hol vesel membrane is ‘n verbetering van ongeveer 30 % in die deurvloei van p-xileen verkry, vergeleke met membraanbuise, by identiese bedryfstoestande. Hol vesels bied ook die verdere voordeel van oppervlak-tot-volume verhoudings van so hoog as 3000 m2/m3 vergeleke met konvensionele membraanbuise. Die gebruik van hierdie tipe sisteem kan deurslaggewend wees in die vermindering van die grootte en koste van deurlatingseenhede in toekomstige xileen-skeidingsprosesse. Die vervaardiging van hoë-kwaliteit nanosaamgestelde MFIalumina membraanvesels is egter onderworpe aan die beskikbaarheid van hoë-kwaliteit vessel-ondersteuningsbasisse. Wat die gebruik van nanosaamgestelde MFI-alumina membraanbuise as ekstraksietipe katalitiese membraanreaktore betref (ekstraksie-tipe zeoliet katalitiese membraanreaktor, of e-ZKMR in hierdie studie) vir m-Xileen isomerisasie in die teenwoordigheid Pt-HZSM-5, bevestig die resultate die potensiaal van e-ZKM reaktore bo konvensionele vaste-bed reaktore (VBR). In die gekombineerde verstelling (met produkte in die permeaat sowel as die retentaat) toon die e-ZKMR ‘n 16 – 18% verbetering in die opbrengs van p-Xileen vergeleke met ‘n ekwivalente VBR by dieselfde bedryfskondisies. Gegrond op die hoë p-Xileen-tot-o- Xileen (p/o) en p-Xileen-tot-m-Xileen (p/m) skeidingsfaktore wat deur die membraan gebied word, is p-Xileen-samestellings in die slegs-permeaat verstelling (produkte in die permeaatstroom) van tussen 95 en 100% in die e-ZKMR verkry. Toe ‘n defek-vrye nanosaamgestelde MFI-alumina membraanbuis met ‘n (p/o) skeidingsfaktor van >400 gebruik is, is p-Xileen met ‘n suiwerheid na aan 100% in die slegs-permeaat verstelling verkry. Die e-ZKMR het ook 100% para-selektiwiteit in die slegs-permeaat verstelling getoon by alle toets-temperature, iets wat onmoontlik is met gewone filmagtige MFI-tipe zeolietmembrane. Om hierdie rede is dit moontlik dat die gebruik van MFI-alumina membrane in ekstraksie-tipe katalitiese membraanreaktore die ontwikkeling van energie-doeltreffende membraangebaseerde prosesse vir die produksie van suiwer p-Xileen kan bevorder. Verder word daar in hierdie tesis verslag gedoen oor die modelering en sensitiwiteitsanalise van ‘n e-ZKMR wat toegerus is met ‘n nanosaamgestelde MFI-alumina membraanbuis as skeidingseenheid vir m-Xileen isomerisasie in die teenwoordigheid van ‘n Pt-HZSM-5 katalis. Die model-uitsette is redelik in ooreenstemming met eksperimentele resultate met absolute fout-persentasies van 17, 27, 0.05 en 19.5 % vir die p-Xileen opbrengs in die gekombineerde verstelling, p-Xileen selektiwiteit in die gekombineerde verstelling, p-Xileen selektiwiteit in die slegs-permeaat verstelling en m-Xileen omsetting, onderskeidelik. Om hierdie rede kan die model die gedrag van ‘n e-ZKMR verduidelik tydens die m-Xileen isomerisasie in die teenwoordigheid van ‘n Pt-HZSM-5 katalis. Die model kan ook aangepas word na e-ZKM reaktore met verskillende konfigurasies, soos hol vesel MFIalumina membraan-gebaseerde e-ZKMRe. Om meer insig te kry in die gedrag van die model op klein veranderinge in sekere ontwerpparameters, is ‘n sensitiwiteitsanalise op die model uitgevoer. Soos verwag, het die sensitiwiteitsanalise gewys dat die intrinsieke eienskappe van die membraan (porositeit, tortuositeit), die effektiewe van membraandikte en die reaktorgrootte (gemeet as die interne deursnit van die reaktor) ‘n noemenswaardige rol speel in die gedrag van die e-ZKMR gedurende p-Xileen produksie vanuit gemengde xilene. MFI-alumina zeolietmembrane met geoptimeerde parameters soos membraanporositeit, -tortuositeit, en –wanddikte mag dalk die oordrag van p-Xileen deur die membraan bevorder en sodoende ‘n hoër vloei van p-Xileen oor die membraan bewerkstellig. Dit sal uiteindelik lei tot ‘n verhoging in die opbrengs van p-Xileen in die slegs-permeaat verstelling. So ver dit vasgestel kon word, is hierdie die eerste verslag in die oop literatuur wat die modelering en sensitiwiteitsanalise van ‘n e-ZKMR, toegerus met nanosaamgestelde MFIalumina membraanbuise as skeidingseenheid vir m-Xileen isomerisasie in die teenwoordigheid van ‘n Pt-HZSM katalis, aanspreek. Verder ondersteun die resultate van hierdie studie vorige navorsingspogings op die gebruik van e-KMRe, met MFI-tipe membrane as skeidingseenhede, vir die produksie van p-Xileen deur middel van m-Xileen isomerisasie in die teenwoordigheid van ‘n geskikte katalis. Verder is nuwe idees ontwikkel, getoets en voorgestel wat dien as ’n stewige basis vir verdere opskalering- en tegno-ekonomiese studies. Sodanige studies is nodig om die vatbaarheid van die tegnologie relatief tot die tradisionele prosesse te bepaal. Ter opsomming, die bemoedigende resultate, soos in die tesis gedokumenteer (en ook gepubliseer in vier ewe-knie beoordeelde internasionale wetenskaplike joernale en vier konferensiestukke), kan as ‘n platform dien vir die ontwikkeling van ’n opgeskaleerde membraan-gebaseerde energie-doeltreffende nywerheidsproses vir die produksie van suiwer p-Xileen deur middel van isomerisasie.
2

Novel gas-separation membranes for intensified catalytic reactors

Escorihuela Roca, Sara 20 May 2019 (has links)
[ES] La presente tesis doctoral se centra en el desarrollo de nuevas membranas de separación de gases, así como su empleo in-situ en reactores catalíticos de membrana para la intensificación de procesos. Para este propósito, se han sintetizado varios materiales, como polímeros para la fabricación de membranas, catalizadores tanto para la metanación del CO2 como para la reacción de síntesis de Fischer-Tropsch, y diversas partículas inorgánicas nanométricas para su uso en membranas de matriz mixta. En lo referente a la fabricación de las membranas, la tesis aborda principalmente dos tipos: orgánicas e inorgánicas. Con respecto a las membranas orgánicas, se han considerado diferentes materiales poliméricos, tanto para la capa selectiva de la membrana, así como soporte de la misma. Se ha trabajado con poliimidas, puesto que son materiales con temperaturas de transición vítrea muy alta, para su posterior uso en reacciones industriales que tienen lugar entre 250-300 ºC. Para conseguir membranas muy permeables, manteniendo una buena selectividad, es necesario obtener capas selectivas de menos de una micra. Usando como material de soporte otro tipo de polímero, no es necesario estudiar la compatibilidad entre ellos, siendo menos compleja la obtención de capas finas. En cambio, si el soporte es de tipo inorgánico, un exhaustivo estudio de la relación entre la concentración y la viscosidad de la solución polimérica es altamente necesario. Diversas partículas inorgánicas nanométricas se estudiaron para favorecer la permeación de agua a través de los materiales poliméricos. En segundo lugar, en cuanto a membranas inorgánicas, se realizó la funcionalización de una membrana de paladio para favorecer la permeación de hidrógeno y evitar así la contaminación por monóxido de carbono. El motivo por el cual se dopó con otro metal la capa selectiva de la membrana metálica fue para poder emplearla en un reactor de Fischer-Tropsch. Con relación al diseño y fabricación de los reactores, durante esta tesis, se desarrolló el prototipo de un microreactor para la metanación de CO2, donde una membrana polimérica de capa fina selectiva al agua se integró para evitar la desactivación del catalizador, y a su vez desplazar el equilibrio y aumentar la conversión de CO2. Por otro lado, se rediseñó un reactor de Fischer-Tropsch para poder introducir una membrana metálica selectiva a hidrogeno y poder inyectarlo de manera controlada. De esta manera, y siguiendo estudios previos, el objetivo fue mejorar la selectividad a los productos deseados mediante el hidrocraqueo y la hidroisomerización de olefinas y parafinas con la ayuda de la alta presión parcial de hidrógeno. / [CAT] La present tesi doctoral es centra en el desenvolupament de noves membranes de separació de gasos, així com el seu ús in-situ en reactors catalítics de membrana per a la intensificació de processos. Per a aquest propòsit, s'han sintetitzat diversos materials, com a polímers per a la fabricació de membranes, catalitzadors tant per a la metanació del CO2 com per a la reacció de síntesi de Fischer-Tropsch, i diverses partícules inorgàniques nanomètriques per al seu ús en membranes de matriu mixta. Referent a la fabricació de les membranes, la tesi aborda principalment dos tipus: orgàniques i inorgàniques. Respecte a les membranes orgàniques, diferents materials polimèrics s'ha considerat com a candidats prometedors, tant per a la capa selectiva de la membrana, així com com a suport d'aquesta. S'ha treballat amb poliimides, ja que són materials amb temperatures de transició vítria molt alta, per al seu posterior ús en reaccions industrials que tenen lloc entre 250-300 °C. Per a aconseguir membranes molt permeables, mantenint una bona selectivitat, és necessari obtindre capes selectives de menys d'una micra. Emprant com a material de suport altre tipus de polímer, no és necessari estudiar la compatibilitat entre ells, sent menys complexa l'obtenció de capes fines. En canvi, si el suport és de tipus inorgànic, un exhaustiu estudi de la relació entre la concentració i la viscositat de la solució polimèrica és altament necessari. Diverses partícules inorgàniques nanomètriques es van estudiar per a afavorir la permeació d'aigua a través dels materials polimèrics. En segon lloc, quant a membranes inorgàniques, es va realitzar la funcionalització d'una membrana de pal¿ladi per a afavorir la permeació d'hidrogen i evitar la contaminació per monòxid de carboni. El motiu pel qual es va dopar amb un altre metall la capa selectiva de la membrana metàl¿lica va ser per a poder emprar-la en un reactor de Fischer-Tropsch. En relació amb el disseny i fabricació dels reactors, durant aquesta tesi, es va desenvolupar el prototip d'un microreactor per a la metanació de CO2, on una membrana polimèrica de capa fina selectiva a l'aigua es va integrar per a així evitar la desactivació del catalitzador i al seu torn desplaçar l'equilibri i augmentar la conversió de CO2. D'altra banda, un reactor de Fischer-Tropsch va ser redissenyat per a poder introduir una membrana metàl¿lica selectiva a l'hidrogen i poder injectar-lo de manera controlada. D'aquesta manera, i seguint estudis previs, el objectiu va ser millorar la selectivitat als productes desitjats mitjançant el hidrocraqueix i la hidroisomerització d'olefines i parafines amb l'ajuda de l'alta pressió parcial d'hidrogen. / [EN] The present thesis is focused on the development of new gas-separation membranes, as well as their in-situ integration on catalytic membrane reactors for process intensification. For this purpose, several materials have been synthesized such as polymers for membrane manufacture, catalysts for CO2 methanation and Fischer-Tropsch synthesis reaction, and inorganic materials in form of nanometer-sized particles for their use in mixed matrix membranes. Regarding membranes manufacture, this thesis deals mainly with two types: organic and inorganic. With regards to the organic membranes, different polymeric materials have been considered as promising candidates, both for the selective layer of the membrane, as well as a support thereof. Polyimides have been selected since they are materials with very high glass transition temperatures, in order to be used in industrial reactions which take place at temperatures around 250-300 ºC. To obtain highly permeable membranes, while maintaining a good selectivity, it is necessary to develop selective layers of less than one micron. Using another type of polymer as support material, it is not necessary to study the compatibility between membrane and support. On the other hand, if the support is inorganic, an exhaustive study of the relation between the concentration and the viscosity of the polymer solution is highly necessary. In addition, various inorganic particles were studied to favor the permeation of water through polymeric materials. Secondly, as regards to inorganic membranes, the functionalization of a palladium membrane to favor the permeation of hydrogen and avoid carbon monoxide contamination was carried out. The membrane selective layer was doped with another metal in order to be used in a Fischer-Tropsch reactor. Regarding the design and manufacture of the reactors used during this thesis, a prototype of a microreactor for CO2 methanation was carried out, where a thin-film polymer membrane selective to water was integrated to avoid the deactivation of the catalyst and to displace the equilibrium and increase the CO2 conversion. On the other hand, a Fischer-Tropsch reactor was redesigned to introduce a hydrogen-selective metal membrane and to be able to inject it in a controlled manner. In this way, and following previous studies, the aim is to enhance the selectivity to the target products by hydrocracking and hydroisomerization the olefins and paraffins assisted by the presence of an elevated partial pressure of hydrogen. / I would like to acknowledge the Spanish Government, for funding my research with the Severo Ochoa scholarship. / Escorihuela Roca, S. (2019). Novel gas-separation membranes for intensified catalytic reactors [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/121139 / TESIS

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