INIQUI 05448
INSTITUTO DE INVESTIGACIONES PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Effect of hydrothermal treatment on Cr/SiO2 mesoporous materials
Autor/es:
PABLO M. CUESTA ZAPATA; MARCELO NAZZARRO; MÓNICA L. PARENTIS; ELIO E. GONZO; NORBERTO A. BONINI
Revista:
CHEMICAL ENGINEERING SCIENCE
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2013 vol. 101 p. 374 - 381
ISSN:
0009-2509
Resumen:
Cr/SiO2 (MCM-41) materials were prepared by the sol-gel method by hydrolysis of tetraethylortosilicate (TEOS) using cetyltrimethylammoniumbromide(CTAB) as a template. The effect of hydrothermal treatment between120-220 ºC on the structural properties was studied. Well ordered Cr/MCM-41with a very narrow pore size distribution was obtained after hydrothermal treatment from RT to 150 ºC.Materials synthesized at higher temperatures (200 or 220 ºC) showed the collapse of the ordered mesoestructure to give mesoporous Cr/SiO2 with anopensurface. Superficial Cr3+/Cr6+ ratio was determined by XPS over materials hydrothermically synthesized at different temperatures, and calcined in air at 300 ºC. The hydrothermal treatment improved the chromium to silica interaction, promoting a higher resistance to form Chromium(VI) sites.The chromium (III) ions incorporated to the silica structure developed acid sites responsible for the 2-PrOH dehydration.
