Preparation of silica gels
Abstract
Abstract SILICA XEROGELS HAVING A NARROW PORE DIAMETER DISTRIBUTION IN THE RANGE OF 300-600 A., AND SURFACE AREAS IN THE RANGE OF FROM 200-500 M.2/G., PORE VOLUMES IN THE RANGE OF 2.0-3.5 CM.3/G. AND THE PROCESS OF PREPARING SUCH XEROGELS COMPRISING CRITICALLY CONTROLLED STEPS OF PRECITATION OF THE SILICA GEL, AGING THE PRECIPITATED SILICA HYDROGEL SLURRY, CONTROLLING THE LEVEL OF ALKALINE MATERIAL IN THE PRECIPITATED HYDROGEL SLURRY BY WASHING THE AGED PRODUCT AND DRYING THE GEL BY AZEOTROPIC DISTILLATION WITH A SOLVENT WHICH IS NON-MISCIBLE WITH WATER. ALSO, A PROCESS FOR PREPARING SUCH XEROGELS WHEREIN THE NON-WATER MISCIBLE SOLVENT IS CONTINUOUSLY RECYCLED SO THAT A MINIMUM AMOUNT OF SOLVENT NEED BE USED.
Inventors
- 👤 H Aboutboul
- 👤 J Krekeler
- 👤 W Kirch
Bibliographic Details
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