The Preparation Of Silica Gel With Big Pore Volume And High Surface Area

Silica gel is a3d space mesh structure of the porous solid material, poredistribution range, with a great surface area, the surface covered with a lot of silanealcohol gene, that has some of the activity. Silica gel can absorb many material, thatmake it become good desiccant, absorbent, catalyst and catalyst carrier and so on,widely used in industrial and agricultural production. The adsorption performance ofsilica gel with rich porous and large specific surface area is inseparable connection, soin order to improve the adsorption performance of silica gel, research and develop alarge pore volume and high surface area silica gel is not allow to ignore.In this paper, reserch the big pore volume and high surface area silica gel, whichis prepared by microwave, specific conclusions are as follows:Adopt thin sulfuric acid and thin sodium silicate as raw materials, using sol-gelmethod, with no water ethanol as a replacement agent replacement, through themicrowave drying prepare the big pore volume and high surface area silica gel.This paper studies the raw material concentration, ageing temperature, ageingtime, alcohol bubble bath ratio, alcohol bubble time, microwave drying strength,microwave drying temperature and activation time of silica gel pore size, volume andspecific surface area of influence.Summarizes the large volume of silica gel preparation high surface area ofprocess conditions for preferential: rare sodium silicate content of silica in control at20%, and the concentration of sulfuric acid was30%, ageing temperature60℃,ageing time30h, acid bubble concentration0.02%, acid bubble time4h, alcoholbubble bath2.5:1.0, alcohol bubble time30h, microwave intensity for550w,microwave drying time of20min, activation temperature of600℃. Thepore volumeof silica is1.5mL/g-2.2mL/g, specific surface area is500m2/g-650m2/g.This process are feasible, simple operation easy to master, the product quality isstable, large pore volume, high specific surface area, low cost. Using the process of theproduction of the silica gel with large pore volume and high specific surface area, canbe used in paper making, wave-ray agents and catalyst etc, and has a broad prospect ofpromotion and significant social benefits and economic benefits.