METHOD OF PREPARING SILICON DIOXIDE Russian patent published in 2002 - IPC

FIELD: manufacture of highly dispersed silicon dioxide, polymers and mineralfillers in chemical industries. SUBSTANCE: prior to treating original silica-containing solution, silica primer is suspended in mineral acid, and solution is treated by making batches into the resulting suspension under agitation conditions at rate of 0.1- 2.0 l/h per 1 l of suspension, temperature of the resulting pulp being maintained at not lower than 50 C. Silica primer is suspended in mineral acid having concentration of not lower than 15%, and amount of varies from 20 to 200 % of weight of silica contained in original silica-containing solution. The result attained comprises increasing filtration characteristics of silicon dioxide deposit and also reducing consumption of water for washing deposit to remove soluble impurities. Method makes it possible to increase significantly efficiency of equipment, to minimize production flowsheets and diminish energy consumption at silicon dioxide deposit drying stage. EFFECT: more efficient preparation method. 3 cl, 12 ex