Use of rice husk ash as only source of silica in the formation of mesoporous materials

• Autor(a) principal: Schwanke,A. J.
• Data de Publicação: 2013
• Outros Autores: Melo,D. M. A., Silva,A. O., Pergher,S. B. C.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Cerâmica (São Paulo. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0366-69132013000100022
• topic: MCM-41; rice husk ash; mesoporous materials

This paper reports the synthesis of molecular sieves similar to MCM-41 using rice husk ash as only source of silica. For comparison purposes, a standard synthesis was performed using aerosil 200 commercial silica. The rice husk silica was obtained by heating treatment at 600 ºC and leaching for 2 h in reflux with HCl 1mol.L-1 and used in the synthesis. The samples prepared were characterized by N2 adsorption, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and thermogravimetric analysis (TG). By type-IV adsorption isotherms, the formation of mesoporous materials was observed. XRD showed the formation of hexagonal unidirectional pore materials similar to MCM-41. By SEM, it could be observed that the rice husk has fibrous aspect and that synthesis using calcined and leached rice husk did not react entirely because silica was only partially dissolved.