New preparation method for mesoporous γ-alumina by selective leaching of calcined kaolin minerals
Authors:
- Kiyoshi OkadaKOKiyoshi Okada
- Hiroshi KawashimaHKHiroshi Kawashima
- Yoshitoshi SaitoYSYoshitoshi Saito
- Shigeo HayashiSHShigeo Hayashi
- Atsuo YasumoriAYAtsuo Yasumori
- 1 January 1995
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of Materials Chemistry
- Vol. 5 (8) , 1241-1244
Abstract
Mesoporous γ-alumina with uniform pore size has been prepared by selective leaching of silica from calcined kaolin minerals, 2SiO2·Al2O3·nH2O. A microtexture of very fine spine)-phase grains, consisting of γ-alumina containing several wt.% of silica, precipitating within an amorphous silica matrix, was obtained by calcining kaolin minerals at around 950 °C. Porous γ-alumina was prepared by selectively dissolving the amorphous silica in KOH solution at temperatures of 25–90 °C. The γ-alumina obtained from kaolinite showed a very narrow unimodal pore size distribution at a radius of around 2-3 nm. The specific surface area was around 270 m2 g–1 and the total pore volume was 0.84 ml g–1. On the other hand, the γ-alumina obtained from tubular halloysite showed a bimodal pore size distribution at radii of around 2–3 nm and 10–20 nm. The specific surface area was ca. 320 m2 g–1 and the total pore volume was 0.69 ml g–1Keywords
This publication has 9 references indexed in Scilit:
- Effect of seeding during precursor preparation on the pore structure of alumina catalyst supportsMicroporous Materials, 1993
- Factors for maintenance of a high surface area of silica-coated α-alumina after heating >1573 KJournal of Materials Chemistry, 1993
- Mesoporous Materials Produced from Novel Trioctahedral Ni-SmectiteJournal of the Ceramic Society of Japan, 1992
- Preparation of alumina aerogel and application to support of combustion catalyst1992
- The control of pore size in alumina catalyst supports: A reviewApplied Catalysis, 1986
- Growth Conditions and Genesis of Spherical and Platy KaoliniteClays and Clay Minerals, 1985
- The preparation of controlled pore aluminaApplied Catalysis, 1984
- Thermal stabilization of an active alumina and effect of dopants on the surface areaJournal of Materials Science, 1976
- The Determination of Pore Volume and Area Distributions in Porous Substances. I. Computations from Nitrogen IsothermsJournal of the American Chemical Society, 1951