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S?ntese e caracteriza??o de materiais mesoporosos inorg?nico-org?nicos para aplica??o na adsor??o de g?s carb?nicoDantas, Taisa Cristine de Moura 26 July 2016 (has links)
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Previous issue date: 2016-07-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A necessidade de encontrar novas tecnologias para a minimiza??o da emiss?o crescente de gases poluentes no planeta se torna cada vez mais urgente. Dos processos estudados atualmente a t?cnica de adsor??o utilizando materiais mesoporosos v?m tendo bastante enfoque. A fam?lia do SBA est? dentro desses materiais, onde pode ser destacado o SBA-15 e SBA-16 como estruturas com propriedades texturais interessantes. O presente trabalho realizou a s?ntese destes materiais de acordo com a metodologia descrita na literatura. Ap?s estas etapas, as estruturas de sil?cio foram funcionalizados atrav?s das t?cnicas de impregna??o com um pol?mero Polietilenimina ramificada com etilendiamina (PEI) em meio metan?lico, onde a rea??o das aminas com a estrutura de sil?cio apresenta car?ter i?nico; e a funcionaliza??o por enxerto com organossilanos, empregando o N-[(3-trimetoxissilil)propil] dietilenotriamina (DT-NNN), onde a estrutura ? formada de um grupo de sil?cio e tr?s aminas. A rea??o dessa mol?cula com a superf?cie de sil?cio ? realizada atrav?s de uma liga??o covalente. Tamb?m houve a funcionaliza??o do SBA-16 utilizando a dupla funcionaliza??o combinando as duas t?cnicas para obter uma maior porcentagem aminas. A parte foi proposta a reciclagem do material de sil?cio SBA-15, onde ap?s a funcionaliza??o, foram tratados termicamente a uma temperatura de 550 ?C para a elimina??o dos grupos org?nicos. A cada etapa de funcionaliza??o foi executada na estrutura uma nova etapa de funcionaliza??o, onde estas foram repetidas por 6 vezes. Os materiais foram caracterizados por t?cnicas f?sico-qu?micas no intuito de verificar a forma??o da estrutura e sua organiza??o. O processo de adsor??o de CO2 puro para o material SBA-16 funcionalizado foi executado em um equipamento volum?trico sob press?o de 1 bar a 45 ?C, onde a amostra E-SBA16-10PEI e CC-SBA16-50PEI exibiram quantidades de adsor??o de 47 mg CO2/g ads e 108 mg CO2/g ads, respectivamente. Os ensaios de adsor??o para o SBA-15 foram realizados tamb?m a 1 bar e 45 ?C, e menos quantidades de CO2 adsorvidos foram reportadas para as amostras com DT e isto pode ser relacionada a perda da efici?ncia das aminas. Esse comportamento n?o foi observado nas amostras impregnadas com PEI. / The need to find new technologies to minimize the increasing emission of greenhouse gases on the planet becomes increasingly urgent. Currently processes studied the adsorption technique using mesoporous materials are having enough focus. The family of the SBA is within these materials, which can be highlighted the SBA-15 and SBA-16 as structures with interesting textural properties. In the present work was carried out the synthesis of these materials according to the methodology described in the literature. After these steps, the silicon structures were functionalized by means of impregnation techniques with a branched polyethylenimine polymer etilendiamina (PEI) in the methanolic medium, where the reaction of amines with the silicon structure has ionic character; and graft functionalization with organosilanes, where we used the N [(3-trimetoxissilil) propyl] diethylenetriamine (DT- NNN) where the structure is formed from a group of silicon and three amines. The reaction of this molecule with the silicon surface is performed through a covalent bond. There was also the functionalization of SBA-16 using double functionalization combining the two techniques to get higher percentage amines. The part was proposed recycling of SBA-15 silicon material, which after functionalization, were heat-treated at a temperature of 550 ?C for the removal of organic groups. Each functionalization step was performed a new structure functionalization step, where they were repeated 6 times. The materials were characterized by physico-chemical techniques in order to verify the formation of structure and organization. The process of pure CO2 adsorption on functionalized SBA-16 materials, was performed on a volumetric equipment under 1 bar pressure at 45 ?C where the sample E-SBA16-10PEI and CC-SBA16-50PEI showing adsorption amounts of 47 mg CO2/g ads and 108 mg CO2/g ads, respectively. Adsorption tests for SBA-15 were also performed at 1 bar and 45 ? C, less amounts of CO2 absorbed were reported out for samples with DT and this is related to loss of efficiency of amines. This behavior was not observed in the samples impregnated with PEI.
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