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Estudo cin?tico da degrada??o t?rmica e catal?tica de petr?leo pesado usando Al-MCM-41

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Previous issue date: 2013-08-09 / The mesoporous nanostructured materials have been studied for application in
the oil industry, in particular Al-MCM-41, due to the surface area around 800 to 1.000
m2 g-1 and, pore diameters ranging from 2 to 10 nm, suitable for catalysis to large
molecules such as heavy oil. The MCM-41 has been synthesized by hydrothermal
method, on which aluminum was added, in the ratio Si/Al equal to 50, to increase the
generation of active acid sites in the nanotubes. The catalyst was characterized by X-ray
diffraction (XRD), surface area by the BET method and, the average pore volume BJH
method using the N2 adsorption, absorption spectroscopy in the infrared Fourier
Transform (FT-IR) and determination of surface acidity with application of a probe
molecule - n-butylamine. The catalyst showed well-defined structural properties and
consistent with the literature. The overall objective was to test the Al-MCM-41 as
catalyst and thermogravimetric perform tests, using two samples of heavy oil with API ?
equal to 14.0 and 18.5. Assays were performed using a temperature range of 30-900 ? C
and heating ratios (β) ranging from 5, 10 and 20 ?C min-1.The aim was to verify the
thermogravimetric profiles of these oils when subjected to the action of the catalyst Al-
MCM-41. Therefore, the percentage ranged catalyst applied 1, 3, 5, 10 and 20 wt%, and
from the TG data were applied two different kinetic models: Ozawa-Flynn-Wall (OFW)
and Kissinger-Akahrira-Sunose (KAS).The apparent activation energies found for both
models had similar values and were lower for the second event of mass loss known as
cracking zone, indicating a more effective performance of Al-MCM-41 in that area.
Furthermore, there was a more pronounced reduction in the value of activation energy
for between 10 and 20% by weight of the oil-catalyst mixture. It was concluded that the
Al-MCM-41 catalyst has applicability in heavy oils to reduce the apparent activation
energy of a catalyst-oil system, and the best result with 20% by weight of Al-MCM-41 / Os materiais mesoporosos nanoestruturados vem sendo estudados para aplica??o
na ind?stria do petr?leo, em especial o Al-MCM-41, devido ? ?rea superficial em torno
de 800-1000 m2g-1 e di?metro de poros variando de 2 a 10 nm, adequado para cat?lise
de mol?culas grandes como petr?leos pesados. O MCM-41 foi sintetizado pelo m?todo
hidrot?rmico, o qual foi adicionado Alum?nio numa propor??o Si/Al igual ? 50, a fim de
aumentar a gera??o de s?tios ?cidos ativos nos nanotubos. O catalisador foi
caracterizado por difra??o de Raios-X (DRX), ?rea superficial pelo m?todo BET e
volume m?dio de poros pelo m?todo BJH atrav?s da adsor??o de N2, espectroscopia de
absor??o na regi?o do infravermelho por Transformada de Fourier (FT-IR) e
determina??o da acidez superficial com aplica??o de uma mol?cula sonda nbutilamina.
O catalisador apresentou propriedades estruturais bem definidas e coerentes
com a literatura. O objetivo geral foi testar o Al-MCM-41 como catalisador e realizar
ensaios termogravim?tricos, utilizando duas amostras de petr?leo pesado com ?API
iguais ? 14,0 e 18,5. Os ensaios foram realizados usando uma faixa de temperatura de
30 900?C, e raz?es de aquecimento (β) variando de 5, 10 e 20 ?Cmin-1. O intuito era
verificar os perfis termogravim?tricos destes petr?leos quando submetidos ? a??o do
catalisador Al-MCM-41. Para tanto, variou-se o percentual de catalisador aplicado in
situ: 1, 3, 5, 10 e 20% em massa e, a partir dos dados termogravim?tricos foram
aplicados dois modelos cin?ticos diferentes: Ozawa-Flynn-Wall (OFW) e Kissinger-
Akahrira-Sunose (KAS). As energias de ativa??o aparente encontradas para ambos os
modelos tinham valores semelhantes e eram menores para o segundo evento de perda de
massa conhecido como zona de craqueamento, indicando uma atua??o mais efetiva do
Al-MCM-41 nessa zona. Al?m disso, constatou-se uma diminui??o mais acentuada no
valor das energias de ativa??o para valores entre 10 e 20% em massa da mistura
catalisador-?leo. Concluiu-se que o Al-MCM-41 possui aplicabilidade catal?tica em
petr?leos pesados diminuindo a energia de ativa??o aparente de um sistema catalisador?leo,
sendo o melhor resultado com 20% em massa de Al-MCM-41

Identiferoai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17781
Date09 August 2013
CreatorsOliveira, Aline Ara?jo Alves de
ContributorsCPF:35530502415, http://lattes.cnpq.br/9770622597949866, Fernandes J?nior, Valter Jos?, CPF:42314070453, http://lattes.cnpq.br/1595902438130772, Coriolano, Ana Catarina Fernandes, CPF:83744479404, http://lattes.cnpq.br/5552621403067808, Ara?jo, Sulene Alves de, CPF:51205645420, http://lattes.cnpq.br/1916903519453512, Ara?jo, Ant?nio Souza de
PublisherUniversidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica
Source SetsIBICT Brazilian ETDs
LanguagePortuguese
Detected LanguageEnglish
Typeinfo:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis
Formatapplication/pdf
Sourcereponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN
Rightsinfo:eu-repo/semantics/openAccess

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