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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
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17609 |
| Date | 22 December 2008 |
| Creators | Costa, Maria Jos? Fonseca |
| Contributors | CPF:35530502415, http://lattes.cnpq.br/9770622597949866, Fernandes J?nior, Valter Jos?, CPF:42314070453, http://lattes.cnpq.br/1595902438130772, Silva, Antonio Osimar Sousa da, CPF:96668253415, http://lattes.cnpq.br/5289388662589522, Pacheco Filho, Jos? Geraldo de Andrade, Ara?jo, Ant?nio Souza de |
| 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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