PROPRIEDADES E AVALIAÇÃO CATALÍTICA DA ZEÓLITA X NANOMÉTRICA CONTENDO CÁTIONS METILAMÔNIO

• Autor(a) principal: Vicente,João G. P.
• Data de Publicação: 2016
• Outros Autores: Lima,Patrícia M., Cardoso,Dilson
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Química Nova (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422016000600655
• topic: X Zeolite; nanoparticles; ion exchange; base catalysis; Knoevenagel condensation

The reduction of zeolite particle is one of the main features currently searched; it is due to the catalytic gains that these materials come in some reactions. In this work two faujasite zeolites of type X were evaluated, a micrometer and nanometric. Zeolites in sodium form were exchanged ionically with methylammonium cations. These materials were evaluated as catalysts in the Knoevenagel condensation reaction. Steric impediments restricted the ion exchange in the micrometer zeolite and have become more predominant due to the increase in the volume of cations. In nanometric sample such impediments were less evident due to the reduction of the particles provide greater accessibility to exchangers cations to inaccessible sodium in micrometer zeolite. The best catalytic performances were achieved with zeolites containing the monomethylammonium cation. The increased of the accessibility and diffusion of the reactants and products through the pores of the nanometric zeolite provided the best butyraldehyde conversions independent the exchanger cation