Processing and characterization of active silica obtained from rice husk ash

The rice husk is a residue of the rice production that has been used more and more as fuel in heat generation for drying rice, due its high calorific value and availability. This combustion produces rice husk ash constituted of amorphous silica as a major component. Rice husk ash is an alternative source for high specific area silica. In this paper processing and characterization of active silica obtained from rice husk ash is presented. The relative amount of silica was increased after burning out the carbonaceous material at different times and temperatures. A 95% silica powder could be produced after heat-treating at 700degreesC for 6 h. The specific surface area of particles was increased after wet milling from 54 to 81 m(2)/g.