Continuous silica production process and silica product prepared from same

摘要

Disclosed herein is a continuous process for preparing a silica product, comprising: (a) continuously feeding an acidulating agent and an alkali metal silicate into a loop reaction zone comprising a stream of liquid medium; wherein at least a portion of the acidulating agent and the alkali metal silicate react to form a silica product in the liquid medium of the loop reaction zone; (b) continuously recirculating the liquid medium through the loop reaction zone; and (c) continuously discharging from the loop reaction zone a portion of the liquid medium comprising the silica product. Silica products and dentifrice compositions comprising the silica products are also disclosed. A continuous loop reactor is also disclosed.

主权项

1. A continuous process for preparing a silica product, comprising: (a) continuously feeding an acidulating agent and an alkali metal silicate into a loop reaction zone comprising a stream of liquid medium; wherein at least a portion of the acidulating agent and the alkali metal silicate react to form a silica product in the liquid medium of the loop reaction zone; (b) continuously recirculating the liquid medium through the loop reaction zone; and (c) continuously discharging from the loop reaction zone a portion of the liquid medium comprising the silica product, wherein the silica product comprises silica particles having an oil absorption value of up to 100 cc/100 g; wherein at least 80% of the silica particles are rounded to well rounded; and wherein the silica particles have a sphericity (S80) factor of greater than 0.9 and a Brass Einlehner Abrasion value of less than 8 mg lost/100,000 revolutions.