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Previous issue date: 2014-09-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Diversos materiais est?o atualmente em estudo para o processo de captura de CO2, a
exemplo dos ?xidos met?licos e ?xidos met?licos mistos, ze?litas, materiais carbon?ceos,
estruturas metal-org?nicas (MOF?s), organos?lica e superf?cies de s?lica modificadas. Neste
trabalho, analisou-se a capacidade de adsor??o de CO2 em materiais mesoporosos de
diferentes estruturas, como o MCM-48 e SBA-15, sem impregna??o e impregnados com
n?quel nas propor??es 5 %, 10 % e 20 % (m/m), denominados como 5Ni-MCM-48, 10NiMCM-48,
20Ni-MCM-48 e 5Ni-SBA-15, 10Ni-SBA-15, 20Ni-SBA-15. Os materiais foram
caracterizados atrav?s das an?lises de difra??o de raios X (DRX), an?lise t?rmica (TG e
DTG), espectroscopia na regi?o do infravermelho com transformada de Fourier (FT-IR),
adsor??o e dessor??o de N2 (BET) e microscopia eletr?nica de varredura (MEV) com EDS. O
processo de adsor??o foi realizado variando-se a press?o de 100 - 4000 kPa e mantendo-se a
temperatura constante e igual a 298 K. Na press?o de 100 kPa, as maiores concentra??es de
adsor??o ocorreram para os materiais 5Ni-MCM-48 (0,795 mmol g-1
) e SBA-15 (0,914 mmol
g
-1
) n?o impregnado, e, na press?o de 4000 kPa, para os materiais MCM-48 (14,89 mmol g-1
)
e SBA-15 (9,97 mmol g-1
) n?o impregnados. Os resultados mostraram que a capacidade de
adsor??o varia positivamente com a ?rea espec?fica, no entanto, apresenta uma depend?ncia
direta com o tipo e geometria dos canais da estrutura porosa. Os dados obtidos foram
ajustados atrav?s dos modelos de Langmuir e Freundlich e os par?metros termodin?micos
avaliados foram energia livre de Gibbs e entropia do sistema de adsor??o / Several materials are currently under study for the CO2 capture process, like the metal
oxides and mixed metal oxides, zeolites, carbonaceous materials, metal-organic frameworks
(MOF's) organosilica and modified silica surfaces. In this work, evaluated the adsorption
capacity of CO2 in mesoporous materials of different structures, such as MCM-48 and SBA-
15 without impregnating and impregnated with nickel in the proportions 5 %, 10 % and 20 %
(m/m), known as 5Ni-MCM-48, 10Ni-MCM-48, 20Ni-MCM-48 and 5Ni-SBA-15, 10NiSBA-15,
20Ni-SBA-15. The materials were characterized by means of X-ray diffraction
(XRD), thermal analysis (TG and DTG), Fourier transform infrared spectroscopy (FT-IR), N2
adsorption and desorption (BET) and scanning electron microscopy (SEM) with EDS. The
adsorption process was performed varying the pressure of 100 - 4000 kPa and keeping the
temperature constant and equal to 298 K. At a pressure of 100 kPa, higher concentrations of
adsorption occurred for the materials 5Ni-MCM-48 (0.795 mmol g-1
) and SBA-15 (0.914
mmol g-1
) is not impregnated, and at a pressure of 4000 kPa for MCM-48 materials (14.89
mmol g-1) and SBA-15 (9.97 mmol g-1) not impregnated. The results showed that the
adsorption capacity varies positively with the specific area, however, has a direct dependency
on the type and geometry of the porous structure of channels. The data were fitted using the
Langmuir and Freundlich models and were evaluated thermodynamic parameters Gibbs free
energy and entropy of the adsorption system
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/19645 |
| Date | 23 September 2014 |
| Creators | Nascimento, Alexsandra Rodrigues do |
| Contributors | 04514998320, http://lattes.cnpq.br/5840621182000517, Vitor Sobrinho, Eledir, 64656969915, http://lattes.cnpq.br/8488499388852606, Santos, Luciene da Silva, 27832155515, Aquino, Fl?via de Medeiros, 05660333486, http://lattes.cnpq.br/5822416945469021, Barros, Joana Maria de Farias, 85239658404, http://lattes.cnpq.br/1016070459137884, Souza, Marcelo Jos? Barros de, Melo, Marcus Antonio de Freitas |
| Publisher | Universidade Federal do Rio Grande do Norte, P?S-GRADUA??O EM ENGENHARIA QU?MICA, UFRN, Brasil |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| 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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