Patent ID: 9096761
Filing Date: 2015-08-04
Classification: C01P,C02F,C08K,C09C,C09D,D21H

Abstract:
1. A process for preparing a surface-reacted calcium carbonate in an aqueous environment comprising the following steps: a) providing at least one ground natural calcium carbonate (GNCC); b) providing at least one water-soluble acid in the form of an aqueous solution having an acid concentration, determined as the equivalent weight of pure acid on the weight of the total solution, corresponding to from 25 to 75%; c) providing gaseous CO d) contacting the GNCC of step a) with the acid of step b) and with the CO (i) the at least one acid of step b) has a pK (ii) following contacting the at least one acid with the GNCC, at least one water-soluble salt is additionally added, wherein the water-soluble salt is a hydrogen-containing salt having a pK