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Previous issue date: 2011-11-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The mesoporous molecular sieves of the MCM-41 and FeMCM-41 type are considered
promissory as support for metals used as catalysts in oil-based materials refine processes and
as adsorbents for environmental protection proposes. In this work MCM-41 and FeMCM41
were synthesized using rice husk ash - RHA as alternative to the conventional silica source.
Hydrothermal synthesis was the method chosen to prepare the materials. Pre-defined
synthesis parameters were 100?C for 168 hours, later the precursor was calcinated at 550?C
for 2 hours under nitrogen and air flow. The sieves containing different proportions of iron
were produced by two routes: introduction of iron salt direct synthesis; and a modification
post synthesis consisting in iron salt 1 % and 5% impregnation in the material followed by
thermal decomposition. The molecular sieves were characterized by X ray diffraction XRD,
Fourier transform infrared spectroscopy FT-IR, X ray fluorescence spectroscopy XFR,
scanning electronic microscopy SEM, specific surface area using the BET method,
Termogravimetry TG. The kinetic model of Flynn Wall was used with the aim of
determining the apparent activation energy of the surfactant remove (CTMABr) in the MCM-
41 porous. The analysis made possible the morphology characterization, identifying the
presence of hexagonal structure typical for mesoporous materials, as well as observation of
the MCM41 and iron of characteristic bands. / As peneiras moleculares mesoporosas do tipo MCM-41 e FeMCM-41, s?o
consideradas promissoras como suporte para metais, usadas como catalisadores em processos
de refino de materiais a base de petr?leo e como adsorventes com o prop?sito de prote??o
ambiental. Neste trabalho MCM-41 e FeMCM-41 foram sintetizadas utilizando a cinza da
casca de arroz CCA, como alternativa para a fonte de s?lica. O m?todo escolhido foi a
s?ntese hidrotermal para o preparo dos materiais, a temperatura de 100 ?C por 168 horas em
estufa, posteriormente foi calcinado a 550 ?C por 2 horas sob fluxo de nitrog?nio e ar. As
peneiras moleculares contendo diferentes propor??es de ferro foram produzidas por duas
rotas: introdu??o do sal de ferro no gel de s?ntese e impregna??o de 1% e 5% de ferro no
MCM-41 sintetizado. As peneiras moleculares foram caracterizadas por difra??o de raios X
DRX, espectroscopia no infravermelho por transformada de Fourier (Fourier transform
infrared spectroscopy FT-IR), espectroscopia de fluoresc?ncia de raios X FRX,
microscopia eletr?nica de varredura MEV, ?rea superficial espec?fica atrav?s do m?todo
BET e Termogravimetria TG. O modelo cin?tico de Flynn Wall foi utilizado com o objetivo
de determinar a energia de ativa??o aparente da remo??o do surfactante (CTMABr) nos poros
do MCM-41. As an?lises possibilitaram a caracteriza??o morfol?gica, identificando a
presen?a da estrutura hexagonal t?pica dos materiais mesoporosos, assim como das bandas
caracter?sticas do MCM41 e do ferro.
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/12727 |
| Date | 28 November 2011 |
| Creators | Miranda, Auristela Carla de |
| Contributors | CPF:04514998320, http://lattes.cnpq.br/5840621182000517, Melo, Dulce Maria de Ara?jo, CPF:06117988320, http://lattes.cnpq.br/3318871716111536, Santos, I?da Maria Garcia dos, CPF:50548220115, http://lattes.cnpq.br/7060067415685353, Andrade, Jo?o Marconi de, CPF:42965462449, Melo, Marcus Ant?nio de Freitas |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ci?ncia e Engenharia de Materiais, UFRN, BR, Processamento de Materiais a partir do P?; Pol?meros e Comp?sitos; Processamento de Materiais a part |
| 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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