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Acid Gas Removal by Superhigh Silica ZSM-5: Adsorption Isotherms of Hydrogen Sulfide, Carbon Dioxide, Methane, and NitrogenRahmani, M., Mokhtarani, B., Mafi, M., Rahmanian, Nejat 05 May 2022 (has links)
Yes / The adsorption of acid gas, including hydrogen sulfide and carbon dioxide, by superhigh silica ZSM-5 was investigated. Equilibrium adsorption isotherms of high-purity hydrogen sulfide and carbon dioxide were measured experimentally using this new sorbent. In addition, methane and nitrogen adsorption isotherms on this MFI-type zeolite were also measured as representative of other natural gas components. To enhance the reliability of the results, the adsorption pressure has been selected up to 20 bar at three different temperatures. Superhigh silica ZSM-5 for the adsorption of hydrogen sulfide shows an impressive result of 3.04 mmol·g–1 at 12 bar and 283 K. This value was 2.69 mmol·g–1 for carbon dioxide at 21 bar and 283 K. The adsorption capacity of H2S on the ZSM-5 is the highest, and N2 is the lowest; the order of the adsorption capacities of components is H2S > CO2 > CH4 > N2. The adsorption heat of different adsorbates is calculated: 13.7 and 29.5 kJ·mol–1 for H2S and CO2, respectively. Physical adsorption has occurred on high-silica ZSM-5, especially for hydrogen sulfide, and this is a great advantage. By increasing the temperature, the adsorption capacity of components on the ZSM-5 decreases, but due to differences in the adsorption heat of the adsorbate, the ideal selectivity for hydrogen sulfide increases. There is a challenge in the choice of the best condition for H2S removal, as, by increasing the temperature, the adsorption capacity of hydrogen sulfide reduces, but the selectivity of the hydrogen sulfide increases as compared to other gases. This phenomenon is not true for the selectivity of other components.
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Ethylene to Liquid Hydrocarbons by Heterogeneously Catalyzed Oligomerization on ZSM-5Halldén, Gustav January 2022 (has links)
The aim is to produce aliphatic liquid hydrocarbons using heterogeneous ethylene oligomerization. Thiscould potentially produce renewable synthetic fuels. Heterogeneous catalysis has some advantages overhomogeneous catalysis regarding some sustainability aspects. To achieve this, a setup was built using a heatedfixed bed reactor with an in-situ has chromatography to study conversion and gaseous products, and ex-situGC as well as NMR for analyzing liquid products. Ethylene was oligomerized on a commercial ZSM-5 zeoliteunder varying temperature conditions and feed gas dilution with hydrogen or helium. The gas and liquidproducts were analyzed and evaluated. Additionally, the ZSM-5 was studied at different silica to alumina ratios. The thesis discusses how conversion, liquid yield and selectivity of gas products using GC together withanalysis of liquid products using H-NMR can be used as a simple and quick evaluation. The liquid product isevaluated by the distribution of olefinic and aromatic hydrocarbon species using the hydrogen signal area inthe characteristic chemical shifts of olefinic and aromatic hydrogen. At 250-400oC, 6 bar of ethylene, with andwithout feed dilution, and WHSV of 204 h-1, conversion was consistently above 95% for the diluted 400oCruns. Though the liquid yield fell to around 6%, compared to the best yield at 18% for the pure 300oC run.Diluting the feed had a positive effect on increasing olefinic hydrogen signal while decreasing aromatichydrogen signal. The difference between diluting with H2 or helium had a surprisingly small effect. Decreasingthe Si/Al ratio had no significant effect on performance, while increasing the Si/Al ratio made the zeolite loseits catalytic ability. With a pure ethylene feed the lowest aromatic hydrogen signal was found at 350oC, whilethe olefinic signal did not vary too much with temperature. With diluted feed the higher temperature did leadto a lower olefinic hydrogen signal and higher aromatic hydrogen signal.
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Influence of Framework n(Si)/n(Al) Ratio on the Nature of Cu Species in Cu-ZSM-5 for NH3-SCR-DeNOxJabłońska, Magdalena, Góra-Marek, Kinga, Bruzzese, Paolo Cleto, Palčić, Ana, Pyra, Kamila, Tarach, Karolina, Bertmer, Marko, Poppitz, David, Pöppl, Andreas, Gläser, Roger 05 August 2024 (has links)
Nanosized Cu-containing ZSM-5 catalysts with different n(Si)/
n(Al) ratio of 18.9–50.5 were prepared by ion-exchange. The
physico-chemical characterization clearly shows that the molar
ratio of framework T atoms influences the nature and distribution
of copper species. According to DR UV-Vis, TPR-H2, EPR, or
FT-IR spectroscopy analyses, the amount of aggregated copper
species increases with increasing the framework n(Si)/n(Al) ratio.
Thus, the activity of the Cu-containing ZSM-5 with n(Si)/n(Al)
ratio of 47.0—50.5 in the selective catalytic NO reduction with
NH3 (NH3-SCR-DeNOx) significantly decreases compared to the
other materials (n(Si)/n(Al) ratio of 18.9—19.6). The reaction
mechanism has been discussed in light of the results of 2D COS
(two-dimensional correlation spectroscopy) analysis of IR spectra
and catalytic properties of the zeolites. The results make
evident that enhanced activity of Cu-containing ZSM-5 in NH3-
SCR-DeNOx is correlated with the formation of different NOx
under the experimental conditions.
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Avalia??o da s?ntese e caracteriza??o de ze?lita ZSM-5 ausente de direcionador org?nico estruturalCaldeira, Vin?cius Patr?cio da Silva 25 February 2011 (has links)
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Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The catalytic processes play a vital role in the worldwide economy, a business that
handles about US$ 13 billion per year because the value of products depends on the catalytic
processes, including petroleum products, chemicals, pharmaceuticals, synthetic rubbers and
plastics, among others. The zeolite ZSM-5 is used as catalyst for various reactions in the area
petrochemical, petroleum refining and fine chemicals, especially the reactions of cracking,
isomerization, alkylation, aromatization of olefins, among others. Many researchers have
studied the hydrothermal synthesis of zeolite ZSM-5 free template and they obtained
satisfactory results, so this study aims to evaluate the hydrothermal synthesis and the
physicochemical properties of ZSM-5 with the presence and absence of template compared
with commercial ZSM-5. The methods for hydrothermal synthesis of zeolite ZSM-5 are of
scientific knowledge, providing the chemical composition required for the formation of
zeolitic structure in the presence and absence of template. Samples of both zeolites ZSM-5 in
protonic form were obtained by heat treatment and ion exchange, according to procedures
reported in the literature. The sample of commercial ZSM-5 was acquired by the company
Sentex Industrial Ltda. All samples were characterized by XRD, SEM, FTIR, TG / DTG /
DSC, N2 adsorption and desorption and study of acidity by thermo-desorption of probe
molecule (n-butylamine), in order to understand their physicochemical properties. The
efficiency of the methods applied in this work and reported in the literature has been proved
by well-defined structure of ZSM-5. According as the evaluation of physicochemical
properties, zeolite ZSM-5 free template becomes promising for application in the refining
processes or use as catalytic support, since its synthesis reduces environmental impacts and
production costs / Os processos catal?ticos desempenham um papel vital na economia mundial, um
neg?cio que movimenta aproximadamente US$13 bilh?es por ano, pois o valor dos produtos
depende dos processos catal?ticos, incluindo os produtos petrol?feros, qu?micos,
farmac?uticos, borrachas sint?ticas e pl?sticos, entre outros. A ze?lita ZSM-5 ? utilizada como
catalisador em rea??es nas ?reas petroqu?mica, petrol?fera e qu?mica fina, destacando-se as
rea??es de craqueamento, isomeriza??o, alquila??o, aromatiza??o de olefinas, entre outras.
Muitos pesquisadores t?m estudado a s?ntese hidrot?rmica da ze?lita ZSM-5 ausente de
direcionador org?nico estrutural e obtiveram resultados satisfat?rios, assim, este estudo visa
avaliar a s?ntese hidrot?rmica e as propriedades f?sico-qu?micas da ZSM-5 com a presen?a e
aus?ncia de direcionador org?nico estrutural, em compara??o com ZSM-5 comercial. Os
m?todos para a s?ntese hidrot?rmica da ze?lita ZSM-5 s?o de conhecimento cient?fico,
fornecendo a composi??o qu?mica necess?ria para a forma??o da estrutura zeol?tica em
presen?a e aus?ncia de direcionador org?nico estrutural. As amostras de ambas as ze?litas
ZSM-5 na forma prot?nica foram obtidas atrav?s de tratamentos t?rmicos e troca i?nica, de
acordo com procedimentos relatados na literatura. A amostra de ZSM-5 comercial foi
concedida pela empresa Sentex Industrial Ltda. Todas as amostras foram caracterizadas por
DRX, MEV, FTIR, TG/DTG/DSC, Adsor??o e dessor??o de N2 e estudo da acidez por
termodessor??o de mol?cula sonda (n-butilamina), a fim de compreender suas propriedades
f?sico-qu?micas. A efici?ncia dos m?todos aplicados no presente trabalho e relatados na
literatura foi comprovada pela estrutura bem definida da ze?lita ZSM-5. Conforme a
avalia??o das propriedades f?sico-qu?micas, a ze?lita ZSM-5 ausente de direcionador org?nico
torna-se promissora para aplica??o em processos de refino ou utiliza??o como suporte
catal?tico, visto que, sua s?ntese reduz os impactos ambientais e custos de produ??o
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Untersuchungen an nickelhaltigen ZSM-5-Zeolith-Katalysatoren zur simultanen Stickoxidreduktion mit Propen / Investigations on nickel containing zeolites of type ZSM-5 for simultaneous reduction of nitric and nitrous oxides with propeneRäuchle, Konstantin 08 February 2006 (has links) (PDF)
Stickoxide (NOx) und Distickstoffoxid (N2O) entstehen bei der Verbrennung fossiler Brennstoffe in Gegenwart von Luft und gehören auf Grund ihrer toxischen bzw. klimaschädigenden Wirkung zu den Luftschadstoffen. In der Arbeit wird die simultane Reduktion von NOx und N2O an nickelbeladenen Zeolithen vom Typ H-ZSM-5 mit Propen als Reduktionsmittel untersucht. Die experimentellen Arbeiten wurden unter realitätsnahen Bedingungen mit einem Katalysatorbett durchgeführt. Der Einfluss des Nickelgehalts und der Acidität des zeolithischen Trägermaterials auf Umsatz und Selektivität der Reduktion werden diskutiert. Ausgehend von den gewonnenen Ergebnissen wird ein wahrscheinlicher Reduktionsmechanismus vorgeschlagen. / Nitric and nitrous oxides (NOx, N2O) are part of toxic and climate damaging airborne pollutants and will be produced by combustion of fossil fuels in present of air. In this work the simultaneous reduction of NOx and N2O with propene has been investigated using nickel impregnated zeolites of type H-ZSM-5 as catalytic active material. The experiments have been done using one catalyst bed and a synthetic gas mixture according to real existing environment conditions. The influence of nickel content as well as acidity of the support material on conversion and selectivity have been discussed. Using the experimental results a possible reaction mechanism has been submitted.
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Metal nanoparticles encapsulated in membrane-like zeolite single crystals : application to selective catalysis / Nanoparticules métalliques encapsulées dans des nanoboites zéolithiques : applications à des réactions de catalyse sélectiveLi, Shiwen 05 May 2015 (has links)
Les matériaux « coeur-coquille » composés d’une nanoparticule métallique encapsulée à l'intérieur de coquilles inorganiques (oxydes, carbone …) attirent de plus en plus l'attention par leurs propriétés particulières, en particulier dans le domaine de la catalyse. Les particules métalliques sont protégées par la coquille, qui empêche entre autres le frittage et la croissance des particules à haute température. Cependant, les coquilles sont généralement méso à macroporeuses et elles ne peuvent pas jouer le rôle de tamis moléculaire pour les molécules de taille nanométrique. En revanche, les zéolithes sont des solides cristallins microporeux dont les pores bien définis permettent une forte discrimination des réactifs basée sur la taille, la forme ou leur coefficient de diffusion. L’objectif de cette thèse visait à la synthèse de catalyseurs de type coeur-coquille dans lesquels la coquille est une zéolite microporeuse de structure MFI (silicalite-1 et ZSM-5), le coeur étant soit une particule de métal noble (Au, Ag, Pt, Pd), soit des alliages de ces différents métaux, soit enfin un métal de transition (Co, Ni, Cu). Ces catalyseurs ont été appliqués dans des réactions d'hydrogénation sélective (aromatiques substitués) et l'oxydation sélective de CO en présence d'hydrocarbures. Nous avons ainsi montré que la coquille zéolithique, tout en protégeant les particules du frittage, modifie la sélectivité des réactions en interdisant aux réactifs volumineux d’atteindre les sites catalytiques / Nanostructured yolk-shell materials, which consist of metal nanoparticle cores encapsulated inside hollow shells, attract more and more attention in material science and catalyst applications during the last two decades. Metal particles are usually highly mono-dispersed in size and isolated from each other by the shell, which prevents growth by sintering at high temperature. Because they are generally made of meso/macroporous oxides or amorphous carbon, shells cannot carry out molecular sieve-type separation of molecules at the nanometric scale. The aim of the present thesis was to synthesize yolk-shell catalyst with microporous zeolite shells (silicalite-1 and ZSM-5), containing noble (Au, Pt, Pd) transition (Co, Ni, Cu) and alloy metal nanoparticles. Zeolites are crystalline microporous solids with well-defined pores capable of discriminating nanometric reactants on the basis of size, shape and diffusion rate. Zeolite-based yolk-shell catalysts have been applied in selective hydrogenation (toluene and mesitylene) and oxidation (CO) reactions in the presence of hydrocarbons. Zeolite shells not only plaid a key role as membranes, thus changing selectivities as compared to conventional supported catalysts, but they also protected metal nanoparticles from sintering under reaction conditions
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Untersuchungen an nickelhaltigen ZSM-5-Zeolith-Katalysatoren zur simultanen Stickoxidreduktion mit PropenRäuchle, Konstantin 19 September 2005 (has links)
Stickoxide (NOx) und Distickstoffoxid (N2O) entstehen bei der Verbrennung fossiler Brennstoffe in Gegenwart von Luft und gehören auf Grund ihrer toxischen bzw. klimaschädigenden Wirkung zu den Luftschadstoffen. In der Arbeit wird die simultane Reduktion von NOx und N2O an nickelbeladenen Zeolithen vom Typ H-ZSM-5 mit Propen als Reduktionsmittel untersucht. Die experimentellen Arbeiten wurden unter realitätsnahen Bedingungen mit einem Katalysatorbett durchgeführt. Der Einfluss des Nickelgehalts und der Acidität des zeolithischen Trägermaterials auf Umsatz und Selektivität der Reduktion werden diskutiert. Ausgehend von den gewonnenen Ergebnissen wird ein wahrscheinlicher Reduktionsmechanismus vorgeschlagen. / Nitric and nitrous oxides (NOx, N2O) are part of toxic and climate damaging airborne pollutants and will be produced by combustion of fossil fuels in present of air. In this work the simultaneous reduction of NOx and N2O with propene has been investigated using nickel impregnated zeolites of type H-ZSM-5 as catalytic active material. The experiments have been done using one catalyst bed and a synthetic gas mixture according to real existing environment conditions. The influence of nickel content as well as acidity of the support material on conversion and selectivity have been discussed. Using the experimental results a possible reaction mechanism has been submitted.
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S?ntese e caracteriza??o de materiais nanoporosos para pir?lise catal?tica de ?leos pesadosCosta, Maria Jos? Fonseca 22 December 2008 (has links)
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Previous issue date: 2008-12-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The present work reports the study of nanoporous structures, aiming at their use in research directed to the current demand of the petroleum industry to value heavy oil. Initially,
two ways were chosen for the synthesis of porous structures from the molecular sieves of type Si-MCM-41. In the first way, the structure MCM-41 is precursory for heteroatom substitutes of silicon, generating catalyst of the type Al-MCM-41 from two different methods of incorporation of the metal. This variation of the incorporation method of Aluminum in the
structure of Si-MCM-41 was carried out through the conventional procedure, where the aluminum source was incorporated to the gel of synthesis, and the procedure post-synthesis, where the Aluminum source was incorporated in catalyst after the synthesis of Si-MCM-41. In the second way, the MCM-41 acts as a support for growth of nanocrystals of zeolite embedded in their mesoporous, resulting in hybrid MCM-41/ZSM-5 catalyst. A comparative
analysis was carried through characterizations by XRD, FTIR, measures of acidity through n-butylamine adsorption for TGA, SEM-XRF and N2 adsorption. Also crystalline aluminosilicate with zeolitic structure MFI of type ZSM-5 was synthesized without using organic templates. Methodologies to the preparation of these materials are related by literature
using conventionally reactants that supply oxides of necessary silicon and aluminum, as well as a template agent, and in some cases co-template. The search for new routes of preparation for the ZSM-5 aimed at, above all, the optimization of the same as for the time and the temperature of synthesis, and mainly the elimination of the use of organic templates, that are material of high cost and generally very toxic. The current study is based on the use of the H2O and Na+ cations playing the role of structural template and charge compensation in the structure. Characterizations by XRD, FTIR, SEM-XRF and N2 adsorption were also conducted for this material in order to compare the samples of ZSM-5 synthesized in the absence of template and those used industrially and synthesized using structuring / O presente trabalho relata o estudo de estruturas nanoporosas, visando o uso em pesquisas que atendam a atual demanda da ind?stria do petr?leo, de valorizar ?leos pesados. Inicialmente, optou-se por duas vertentes para a s?ntese de estruturas porosas a partir da peneira molecular do tipo Si-MCM-41. Na primeira vertente, a estrutura MCM-41 ?
precursora para hetero?tomos substituintes do sil?cio, gerando catalisadores do tipo Al-MCM-41 a partir de dois diferentes m?todos de incorpora??o do metal. Essa varia??o do
m?todo de incorpora??o do Alum?nio na estrutura do Si-MCM-41 se deu atrav?s do procedimento convencional, no qual a fonte de alum?nio foi incorporada ao gel de s?ntese e do
procedimento p?s-s?ntese, no qual a fonte de Alum?nio foi incorporada ao catalisador ap?s a s?ntese do Si-MCM-41. Na segunda vertente, o MCM-41 age como suporte para o
crescimento de nanocristais de ze?lita embutidos nos seus mesoporos, resultando no catalisador h?brido MCM-41/ZSM-5. Uma an?lise comparativa foi realizada atrav?s de
caracteriza??es por XRD, FTIR, medidas de acidez atrav?s de dessor??o de n-butilamina por TGA, SEM-XRF e Adsor??o de N2. Tamb?m foi sintetizado um aluminossilicato cristalino
com estrutura zeol?tica MFI do tipo ZSM-5, na aus?ncia total de direcionador org?nico. Metodologias relacionadas ? prepara??o desses materiais s?o relatadas pela literatura
utilizando-se convencionalmente reagentes que forne?am os ?xidos de sil?cio e de alum?nio necess?rios, bem como um agente direcionador, e em alguns casos at? co-direcionadores. A busca por novas rotas de prepara??o para a ZSM-5 visou, sobretudo, a otimiza??o da mesma no que se refere ao tempo e ? temperatura de s?ntese, e principalmente a elimina??o do uso dos direcionadores org?nicos, que s?o materiais de alto custo e geralmente muito t?xicos. O
atual estudo se baseia na utiliza??o da H2O e dos c?tions Na+ desempenhando o papel de direcionamento estrutural e compensa??o de cargas na estrutura. Caracteriza??es por XRD, FTIR, SEM-XRF e Adsor??o de N2 tamb?m foram realizadas para esse material, a fim de comparar as amostras de ZSM-5 sintetizadas na aus?ncia do direcionador e aquelas utilizadas industrialmente e sintetizadas utilizando estruturantes
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Influence de la symétrie et de la taille de la molécule adsorbée sur le processus d'adsorption des composés éthyléniques sur une zéolithe de topologie MFIBernardet, Véronique 12 December 2005 (has links) (PDF)
Cette étude s'inscrit dans le cadre de la compréhension des isothermes à sous-marche observées durant l'adsorption, sur les zéolithes de type MFI, de certains composés organiques. Pour cela, le processus d'adsorption de l'éthylène et du tétraméthyléthylène a été étudié en premier lieu par gravimétrie et en second lieu par spectroscopie infrarouge in situ. Cette dernière technique permet de suivre simultanément les modifications de l'adsorbant et de l'adsorbat. L'analyse de ces données laisse supposer que la sous-marche dans l'isotherme d'adsorption peut être expliquée en tenant compte simultanément de la symétrie et de la taille de la molécule adsorbée. En plus des bandes infrarouge caractéristiques de l'adsorbant et de la phase adsorbée, une bande émergeante est mise en évidence. Elle peut être considérée comme une empreinte du processus d'adsorption.
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Síntese de membranas zeolíticas (ZSM-5/y-ALUMINA e ZSM-5/a-ALUMINA) por Pore-Plugging para permeação de gás N2. / Synthesis of zeolite membranes (ZSM-5 / y-ALUMINA and ZSM-5 / a-ALUMINA) by Pore-Plugging for N2 gas permeationSCHEIBLER, Janaina Rafaella. 23 March 2018 (has links)
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Previous issue date: 2015 / Entre as membranas inorgânicas microporosas, as membranas zeolíticas constituem
uma tecnologia promissora, devido às suas potenciais aplicações normalmente
na desidratação do álcool, separação de moléculas de gás, separação de isômeros
ou em processos químicos, incluindo reações de esterificação. Sob este aspecto,
torna-se imprescindível o estudo das rotas de preparação desses materiais, visando
desenvolver produtos com qualidade e a baixo custo. Portanto, a inovação deste
estudo se dá na síntese de membranas zeolíticas via método de síntese poreplugging
visando a utilização das membranas inorgânicas para permeação gasosa
de N2. Neste trabalho foram desenvolvidos os seguintes materiais: zeólita ZSM-5,
membranas cerâmicas (γ-alumina e α-alumina) e as membranas zeolíticas (ZSM5/γ-alumina e ZSM-5/α-alumina). A zeólita ZSM-5 foi sintetizada por meio do método
hidrotérmico. As membranas cerâmicas (γ-alumina e α-alumina) foram preparadas a
partir da técnica de conformação de pós cerâmicos e posteriormente submetidas à sinterização a uma temperatura de 1000 ºC/1h e 1200 ºC/1h respectivamente. A
preparação das membranas zeolíticas (ZSM-5/γ-alumina e ZSM-5/α-alumina) foi
realizada com base no método pore in plugging. As amostras foram caracterizadas a
partir das técnicas de difração de raios X e Microscopia Eletrônica de Varredura. Os
resultados experimentais permitem diversas conclusões acerca do desenvolvimento
dos materiais: zeólita ZSM-5, membranas cerâmicas (γ-alumina e α-alumina) e
membranas zeolíticas (ZSM-5/γ-alumina e ZSM-5/α-alumina). A partir da difração de
raios X, foi possível verificar que o método de síntese empregado, foi efetivo na
obtenção da zeólita ZSM-5. O difratograma apresentou picos característicos de uma
zeólita ZSM-5 quando comparada ao padrão. Os resultados obtidos por DRX para
as membranas cerâmicas (γ-alumina e α-alumina) demonstraram a formação de
picos característicos do óxido de alumínio, os materiais são cristalinos e puros. Para
o método pore-plugging pode se dizer que é um método promissor, pois mostrou
uma formação satisfatória da camada zeolítica no resultado do DRX de ambas as
membranas zeolíticas (ZSM-5/γ-alumina e ZSM-5/α-alumina). / Among the microporous inorganic membranes, zeolite membranes are a promising
technology due to their potential applications normally in alcohol dehydration,
separation of gas molecules, separation of isomers or chemical processes, including
esterification reactions. In this regard, it is essential to study the preparation of these
materials routes in order to develop products with quality and low cost. Therefore,
innovation of this study gives the synthesis of zeolite membranes via pore-plugging
synthesis method aimed at the use of inorganic membranes for gas permeation N2.
In this work the following materials were developed: ZSM-5 zeolite, ceramic
membranes (γ-alumina and α-alumina) and zeolitic membranes (ZSM-5/γ-alumina
and ZSM-5/α-alumina). Zeolite ZSM-5 was synthesized by the hydrothermal method.
Ceramic membranes (γ-alumina and α-alumina) were prepared from the ceramic
powder forming technique, and subsequently subjected to a sintering temperature of
1000 °C/1h and 1200 °C/1h respectively. The preparation of zeolite membranes
(ZSM-5/γ-alumina and ZSM-5/α-alumina) was carried out based on the method in
pore plugging. The samples were characterized from the techniques of X diffraction
and scanning electron microscopy rays. The experimental results allow several
conclusions about the development of materials: zeolite ZSM-5, ceramic membranes
(γ-alumina and α-alumina) and zeolite membranes (ZSM-5/γ-alumina and ZSM-5/αalumina).
From the X-ray diffraction, it found that the method of synthesis used was
effective in obtaining the zeolite ZSM-5. The XRD pattern showed peaks
characteristic of ZSM-5 compared to the standard. The results obtained by XRD
ceramic membranes (γ-alumina and α-alumina) showed the formation of peaks
characteristic of aluminum oxide, the materials are crystalline and pure. For the poreplugging
method can be said to be a promising method because it showed a
satisfactory formation of the zeolite layer on the result of XRD both zeolite
membranes (ZSM-5/γ-alumina and ZSM-5/α-alumina).
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