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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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