METHOD TO PRODUCE FINE-GRAINED CHEMICALLY SETTLED CALCIUM CARBONATE WITH SPHERICAL FORM OF PARTICLES Russian patent published in 2003 - IPC

FIELD: chemical industry; production of chalk. SUBSTANCE: the invention presents technologies of production of chalk and can be used in chemical industry, production of pigments, varnishes, paints, fillers as well as the method of production of the fine-grained chemically deposited calcium carbonate with a spherical form of particles. The method includes a synthesis a settling with the help of simultaneous feeding into a reacting agitated mixture of the reagent containing ions of calcium, and the carbonating reagent with following separation of the settling from the solution and drying of the product. At the synthesis as the reagent containing ions of calcium, they use an aqueous solution of calcium chloride, and as the carbonating reagent a water solution of sodium carbonate is used. At that during the synthesis the values of calcium chloride and sodium carbonate streams are kept permanent, and surplus of ions of Ca²⁺ is kept permanent and the modifier is introduced. EFFECT: production of the fine-grained calcium carbonate with average particle size of 1.8 -22 micron with spherical form, high purity allowing its use in perfumery. 6 cl, 1 tbl