Artículos de revistas
Porous silica matrix obtained from pyrex class by hydrothermal treatment: Characterization and nature of the porosity
Fecha
2003-07-01Registro en:
Journal of the American Ceramic Society, v. 86, n. 7, p. 1196-1201, 2003.
0002-7820
10.1111/j.1151-2916.2003.tb03447.x
WOS:000184281300022
2-s2.0-0041842604
4284809342546287
7182671143702858
Autor
Universidade Estadual Paulista (Unesp)
Universidade Federal de São Carlos (UFSCar)
Institución
Resumen
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.