The influence of swelling agents molecular dimensions on lamellar morphology of MWW-type zeolites active for fructose conversion

• Autor(a) principal: Pergher, Sibele Berenice Castellã
• Data de Publicação: 2017
• Outros Autores: Schwanke, Anderson Joel, Díaz, Urbano, Corma, Avelino
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/jspui/handle/123456789/29599
• topic: MWW zeolites; Swelling; Pillaring; Hierarchical materials; Fructose dehydration

A new route to obtain pillared, disordered or desilicated MWW-type zeolites was developed assisted by quaternary ammonium surfactants with different hydrocarbon tail size acting as swelling agents (C12TAþ, C16TAþ, C18TAþ) and TPAþ both exchanged to their hydroxide forms instead of only one swelling agent (CnTAþ or TPAþ) in hydroxide form. Effect of surfactant concentration and swelling conditions were determinant to obtain MWW-type zeolites with different lamellar organization and spatial distribution of individual zeolitic layers. Specifically, soft swelling at 25 C with C12TAþ preserved layer structure reaching a final disordered/pillared structure while pillared structures are obtained in the case of materials swollen with C16TAþ and C18TAþ. Aggressive swelling processes at 80 C favored desilication, damaging the layers structure in case of C12TAþ while pillared materials are obtained after swollen with C16TAþ and C18TAþ surfactants. It was proved that both swelling agents in hydroxide forms combining with swelling and pillaring procedure influenced on physico-chemical and morphological nature of MWW-type materials due to the particular conditions used. The obtained derivative MWW zeolites with different morphology, order and accessibility levels were firstly evaluated by catalytic dehydration of fructose to 5-hydroxymethylfurfural (5-HMF) showing superior activity compared to beta zeolites reported in literature