Foamed silica gel - of reduced hygroscopicity

摘要

Particulate silica gel of + 80 mesh size and specific surface is not 500 m2/g is prefired at 500 - 800 degrees C to obtain a product which losses is not >5 wt.% on ignition at 1,000 - 1,450 degrees C to effect foaming. The initial gel is substantially free from adsorbed water. The foamed silica gel which is used as a dessicant and catalyst carrier, has a considerably reduced specific surface, essentially vitreous in nature. This significantly reduces the hygroscopicity of the material, which is crack-free and isoporous.