NOVEL METHOD OF PRODUCING PRECIPITATED SILICON DIOXIDE Russian patent published in 2016 - IPC C01B33/193 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing precipitated silicon dioxide. Method involves reaction of silicate with acid to produce a suspension of silicon dioxide, further separation and drying of the suspension. Note here that during reaction of silicate with acid there is initially formed a starting material containing water with pH from 2 to 5. Then into the starting material there is simultaneously added silicate and acid so that to maintain pH equal to 2-5. Silicate is added to obtain pH from 7 to 10. Simultaneously silicate and acid is added so that pH of the reaction medium is from 7 to 10. Then acid is added to obtain pH from 2.5 to 5.3. After that, the reaction medium is brought into contact with acid and silicate to obtain pH from 2.5 to 5.3. At that, the acid used during at least one of the steps, is a concentrated acid.

EFFECT: there is ensured higher productivity of the method, as well as reduction of the amount of consumed power and/or water.

12 cl