A process for the preparation of finely divided precipitated silica

摘要

The present invention provides a process for the preparation of finely divided precipitated silica. Finely divided precipitated silica is prepared by neutralization of alkali silicate solution, under continuous stirring, at 60 to 9O0 °C in presence of alkali metal salt as coagulating agent, in various neutralization steps during which neutralization is interrupted for specific time. Further acidic silica sol, is added until 60 to 80 % of total alkali is neutralized. The reaction mixture is then aged at least for 3 minute under continuous agitation, followed by circulation through centrifugal pump at an appropriate rate.