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Previous issue date: 2013-07-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The synthesis of MFI-type zeolite membranes was carried by the process in situ or
hydrothermal crystallization. We studied the homogenization time of the room
temperature and gel filtration just before the crystallization step performed out in an oven,
thus obtaining a more uniform zeolite film. The powder synthesized zeolite (structure
type MFI, Silicalite) was characterized by several complementary techniques such as Xray
diffraction (XRD), scanning electron microscopy (SEM), thermal analysis,
temperature programmed desorption (TPD), Fourier Transform infrared spectroscopy
(FTIR) and textural analysis by nitrogen adsorption (specific surface area). For the
purpose of evaluating the quality of the layer supported on the ceramic support, N2
permeation tests were carried starting from room temperature to 600 ?C, where values
were observed values more appropriate permeation from 200 ?C. With the data obtained,
it was made into a graph of temperature versus permeation function, the curve of surface
diffusion was found. For scanning electron microscopy, we observed the formation of
homogeneous crystals and the zeolite film showed no fissures or cracks, indicating that
the process of synthesis and subsequent treatments not damaged the zeolite layer on the
support. Carried permeation studies were found values ranging from 3.64x10-6 to
3.78x10-6, 4.71x10-6 to 5.02x10-6, to pressures 20 and 25 psi, respectively. And the
mixture xylenes/N2 values were between 5.39x10-6 to 5.67x10-6 and 8.13x10-6 to
8.36x10-6, also for pressures of 20 and 25 psi. The values found for the separation factor
were 15.22 at 400 ?C in the first experiment and 1.64 for the second experiment at a
temperature of 150 ?C. It is concluded that the Silicalite membrane was successfully
synthesized and that it is effective in the separation of binary mixtures of xylenes / A s?ntese de membranas zeol?ticas do tipo MFI foi realizada pelo processo de cristaliza??o
in situ ou hidrot?rmica. Foi estudado o tempo de homogeneiza??o do gel em temperatura
ambiente e filtra??o do mesmo antes da etapa de cristaliza??o efetuada em estufa,
obtendo-se um filme zeol?tico uniforme. O p? da ze?lita sintetizada (estrutura tipo MFI,
Silicalita) foi caracterizado por diversas t?cnicas complementares, como: difra??o de
raios X (DRX), microscopia eletr?nica de varredura (MEV), an?lise t?rmica, dessor??o a
temperatura programada (TPD), infravermelho por transformada de Fourier (FTIR) e
an?lise textural por adsor??o de nitrog?nio (?rea espec?fica). Com a finalidade de avaliar
a qualidade da camada suportada sobre o suporte cer?mico, testes de permea??o com N2
foram efetuados partindo da temperatura ambiente at? 600 ?C, onde foram observados
valores mais adequados de permea??o a partir dos 200 ?C. Com os dados obtidos
confeccionou-se um gr?fico em fun??o da temperatura versus a permea??o, a curva
encontrada foi de difus?o superficial. Por microscopia eletr?nica de varredura, observouse
a forma??o de cristais homog?neos e que o filme zeol?tico n?o apresentava fissuras ou
rachaduras, indicando que o processo de s?ntese e tratamentos posteriores n?o danificaram
a camada de ze?lita sobre o suporte. Realizando estudos de permea??o foram verificados
valores que variam entre 3,64x10-6 a 3,78x10-6 e 4,71x10-6 a 5,02x10-6, para press?es de
20 e 25 psi, respectivamente. Para a mistura xilenos/N2 os valores foram de 5,39x10-6 a
5,67x10-6 e 8,13x10-6 a 8,36x10-6, tamb?m para press?es de 20 e 25 psi. Os valores
encontrados para o fator de separa??o foram de 15,22 em 400 ?C no primeiro experimento
e 1, 64 para o segundo experimento em uma temperatura de 150 ?C. Conclui-se que a
membrana Silicalita foi sintetizada com sucesso e que a mesma ? efetiva na separa??o de
misturas bin?rias de xilenos
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17704 |
| Date | 22 July 2013 |
| Creators | Rigo, Reus Tiago |
| Contributors | CPF:50942611004, http://lattes.cnpq.br/5249001430287414, Vitor Sobrinho, Eledir, CPF:64656969915, http://lattes.cnpq.br/8488499388852606, Gusm?o, Katia Bernardo, CPF:51985764091, http://lattes.cnpq.br/8664708384378316, Pergher, Sibele Berenice Castella |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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