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Previous issue date: 2013-04-17 / In this work were synthesized and characterized the materials mesoporous SBA-15 and Al-
SBA-15, Si / Al = 25, 50 and 75, discovered by researchers at the University of California-
Santa Barbara, USA, with pore diameters ranging from 2 to 30 nm and wall thickness from
3.1 to 6.4 nm, making these promising materials in the field of catalysis, particularly for
petroleum refining (catalytic cracking), as their mesopores facilitate access of the molecules
constituting the oil to active sites, thereby increasing the production of hydrocarbons in the
range of light and medium. To verify that the materials used as catalysts were successfully
synthesized, they were characterized using techniques of X-ray diffraction (XRD), absorption
spectroscopy in the infrared Fourier transform (FT-IR) and adsorption nitrogen (BET).
Aiming to check the catalytic activity thereof, a sample of atmospheric residue oil (ATR)
from the pole Guamar?-RN was performed the process by means of thermogravimetry and
thermal degradation of catalytic residue. Upon the curves, it was observed a reduction in the
onset temperature of the decomposition process of catalytic ATR. For the kinetic model
proposed by Flynn-Wall yielded some parameters to determine the apparent activation energy
of decomposition, being shown the efficiency of mesoporous materials, since there was a
decrease in the activation energy for the reactions using catalysts. The ATR was also
subjected to pyrolysis process using a pyrolyzer with gas chromatography coupled to a mass
spectrometer. Through the chromatograms obtained, there was an increase in the yield of the
compounds in the range of gasoline and diesel from the catalytic pyrolysis, with emphasis on
Al-SBA-15 (Si / Al = 25), which showed a percentage higher than the other catalysts. These
results are due to the fact that the synthesized materials exhibit specific properties for
application in the process of pyrolysis of complex molecules and high molecular weight as
constituents of the ATR / No presente trabalho foram sintetizados e caracterizados os materiais mesoporosos SBA-15
e Al-SBA-15, Si/Al= 25, 50 e 75, descobertos por pesquisadores da Universidade da
Calif?rnia- Santa B?rbara- EUA, tendo di?metro de poros variando entre 2 a 30 nm e
espessura das paredes de 3,1 - 6,4 nm, tornando estes materiais promissores na ?rea da
cat?lise, especificamente para o refino do petr?leo (craqueamento catal?tico), j? que seus
mesoporos facilitam o acesso das mol?culas constituintes do petr?leo aos s?tios ativos,
aumentando assim a produ??o de produtos na faixa dos hidrocarbonetos leves e m?dios.
Para verificar se os materiais utilizados como catalisadores haviam sido sintetizados com
sucesso, os mesmos foram caracterizados atrav?s das t?cnicas de difra??o de raios-X (DRX),
espectroscopia de absor??o na regi?o do infravermelho com transformada de Fourier (FTIR)
e adsor??o de nitrog?nio (BET). Com o intuito de verificar a atividade catal?tica dos
mesmos, utilizou-se uma amostra de Res?duo Atmosf?rico de petr?leo (RAT), proveniente
do P?lo de Guamar?- RN, realizando-se atrav?s da termogravimetria o processo de
degrada??o t?rmica e catal?tica do res?duo. Mediante as curvas obtidas, observou-se uma
redu??o na temperatura de in?cio do processo de decomposi??o catal?tica do RAT. Pelo
modelo cin?tico proposto por Flynn- Wall obtiveram-se alguns par?metros para
determina??o da energia de ativa??o aparente das decomposi??es, ficando evidenciada a
efici?ncia dos materiais mesoporosos, j? que houve uma diminui??o da energia de ativa??o
para as rea??es utilizando os catalisadores. O RAT tamb?m foi submetido ao processo de
pir?lise utilizando-se um pirolisador com cromatografia gasosa, acoplado a um
espectr?metro de massa. Mediante os cromatogramas obtidos, observou-se um aumento no
rendimento dos compostos na faixa da gasolina e diesel oriundos da pir?lise catal?tica, com
?nfase para o Al-SBA-15 (Si/Al= 25), que apresentou um percentual superior aos demais
catalisadores. Esses resultados se devem ao fato dos materiais sintetizados exibirem
propriedades espec?ficas, para aplica??o no processo de pir?lise de mol?culas complexas e
com alto peso molecular, como os constituintes do RAT
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17783 |
| Date | 17 April 2013 |
| Creators | Castro, Kesia Kelly Vieira de |
| Contributors | CPF:35530502415, http://lattes.cnpq.br/9770622597949866, Coriolano, Ana Catarina Fernandes, CPF:83744479404, http://lattes.cnpq.br/5552621403067808, Guedes, Ana Paula de Melo Alves, CPF:03330987499, http://lattes.cnpq.br/5738717177200782, Ara?jo, Sulene Alves de, CPF:51205645420, http://lattes.cnpq.br/1916903519453512, Bicudo, Tatiana de Campos, CPF:25935096862, http://lattes.cnpq.br/2712586287719863, 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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