Porous silica matrix obtained from pyrex class by hydrothermal treatment: Characterization and nature of the porosity
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Data
2003-07-01
Autores
Sigoli, Fernando Aparecido [UNESP]
Feliciano, Sérgio [UNESP]
Giotto, Marcus Vinicius
Davolos, Marian Rosaly [UNESP]
Jafelicci Júnior, Miguel [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Amer Ceramic Soc
Resumo
A novel porous silica matrix has been prepared from Pyrex glass, using hydrothermal treatment under saturated-steam condition. This process makes it possible to obtain, in one step, a silica support formed of a homogeneously distributed and interconnected macropore microstructure. The new matrix contains silanol groups that can be used in reactions of surface modification to provide a hybrid material and a selective macrofiltration membrane, and also it can improve chemical inertness. The porous matrix is noncrystalline as obtained and, after thermal treatment at temperatures higher than 950degreesC, exhibits an X-ray pattern characteristic of alpha-cristobalite and low volume contraction. The present samples were characterized by scanning electron microscopy, mercury intrusion porosimetry, nitrogen adsorption-desorption isotherms, infrared spectroscopy, X-ray powder diffractometry, atomic absorption, and high-resolution solid-state nuclear magnetic resonance. The results present a new way of producing a macroporous silica matrix.
Descrição
Palavras-chave
Adsorption isotherms, Desorption, Glass, Heat treatment, Hydrothermal synthesis, Infrared spectroscopy, Microstructure, Nuclear magnetic resonance, Porosity, Porous materials, Scanning electron microscopy, Steam, Surface treatment, X ray powder diffraction, Mercury intrusion porosimetry, Silica
Como citar
Journal of the American Ceramic Society, v. 86, n. 7, p. 1196-1201, 2003.