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Previous issue date: 2013-06-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The processing of heavy oil produced in Brazil is an emergency action and a strategic
plan to obtain self-sufficiency and economic surpluses. Seen in these terms, it is indispensable
to invest in research to obtain new catalysts for obtaining light fraction of hydrocarbons from
heavy fractions of petroleum. This dissertation for the degree of Doctor of Philosophy reports
the materials preparation that combine the high catalytic activity of zeolites with the greater
accessibility of the mesoporosity, more particularly the HZSM-5/MCM-41 hybrid, done by
synthesis processes with less environmental impact than conventional ones. Innovative
methodologies were developed for the synthesis of micro-mesoporous hybrid material by dual
templating mechanism and from crystalline zeolitic aluminosilicate in the absence of organic
template. The synthesis of hybrid with pore bimodal distribution took place from one-single
organic directing agent aimed to eliminate the use of organic templates, acids of any kind or
organic solvents like templating agent of crystalline zeolitic aluminosilicate together with
temperature-programmed microwave-assisted, making the experimental procedures of
preparation most practical and easy, with good reproducibility and low cost. The study about
crystalline zeolitic aluminosilicate in the absence of organic template, especially MFI type, is
based on use of H2O and Na+ cation playing a structural directing role in place of an organic
template. Advanced characterization techniques such as X-Ray Diffraction (XRD), Fourier
Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Highresolution
Transmission Electron Microscopy (HRTEM), Adsorption of N2 and CO2, kinetic
studies by Thermogravimetric Analysis (TGA) and Pyrolysis coupled to Gas
Chromatography/Mass Spectrometry (Pyrolysis-GC/MS) were employed in order to evaluate
the synthesized materials. Achieve the proposed objectives, has made available a set of new
methodologies for the synthesis of zeolite and hybrid micro-mesoporous material, these
suitable for catalytic pyrolysis of heavy oils aimed at producing light fraction / O processamento do petr?leo pesado produzido no Pa?s ? uma a??o emergencial e
estrat?gica para obter a auto-sufici?ncia e super?vits econ?micos. Neste sentido, ?
indispens?vel o investimento em pesquisas de novos catalisadores para obten??o de derivados
leves a partir de fra??es pesadas do petr?leo. O trabalho de doutorado aqui reportado dedicouse
? prepara??o de materiais que combinem, numa ?nica estrutura, a elevada atividade
catal?tica de ze?litas, com melhor acessibilidade de materiais mesoporosos, como a estrutura
h?brida HZSM-5/MCM-41, utilizando processos de s?ntese com menor impacto ambiental que
os convencionais. Metodologias inovadoras foram desenvolvidas para a s?ntese do catalisador
h?brido micro-mesoporoso ou ze?lito-mesoporoso por mecanismo de direcionamento
estrutural via duplo agente diretor org?nico e tamb?m a partir de estrutura zeol?tica sintetizada
na aus?ncia total de direcionador org?nico. Esse ?ltimo, tamb?m chamado de s?ntese do
h?brido com distribui??o bimodal de poros a partir de um ?nico agente diretor org?nico, visou
eliminar o uso dos direcionadores org?nicos, ?cidos de qualquer natureza ou solventes
org?nicos como molde estrutural da estrutura zeol?tica em conjunto com o m?todo
hidrot?rmico assistido por irradia??o via micro-ondas, tornando o procedimento experimental
de prepara??o pr?tico e simples, com boa reprodutibilidade e menor custo. A metodologia de
prepara??o da ze?lita MFI do tipo ZSM-5 utiliza H2O e c?tions Na+ no papel de
direcionamento estrutural e compensa??o de cargas na estrutura. T?cnicas relevantes de
caracteriza??o, como Difra??o de Raios-X (XRD), Espectroscopia no Infravermelho com
Transformada de Fourier (FTIR), Microscopia Eletr?nica de Varredura (SEM), Microscopia
Eletr?nica de Transmiss?o de Alta Resolu??o (HRTEM), Adsor??o de N2 e CO2, estudos
cin?ticos via An?lises Termogravim?tricas (TGA) e Pir?lise acoplada ? Cromatografia
Gasosa/Espectrometria de Massas (Pyrolysis-GC/MS), foram empregadas no intuito de
avaliar os materiais sintetizados. Alcan?ados os objetivos propostos, disponibilizou-se um
conjunto de novas metodologias para s?ntese de catalisadores zeol?ticos e h?bridos micromesoporosos,
estes adequados para pir?lise catal?tica de ?leos pesados visando ? produ??o de
derivados leves
Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17786 |
Date | 03 June 2013 |
Creators | Costa, Maria Jos? Fonseca |
Contributors | CPF:35530502415, http://lattes.cnpq.br/9770622597949866, Guedes, Ana Paula de Melo Alves, CPF:03330987499, http://lattes.cnpq.br/5738717177200782, Barros, Joana Maria de Farias, CPF:85239658404, http://lattes.cnpq.br/1016070459137884, Fonseca, Jos? Luis Cardozo, CPF:90623207753, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788562T6, Pontes, Luiz Antonio Magalh?es, CPF:65440587772, http://lattes.cnpq.br/2865282329757428, 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/doctoralThesis |
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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