METHOD FOR PRODUCING CALCIUM SILICATE Russian patent published in 2023 - IPC C01B33/24 

FIELD: chemical industry.

SUBSTANCE: method for producing calcium silicate includes hydrothermal treatment of the initial mixture of phosphorite concentrate (PC) and silicon dioxide at the ratio, wt.%: PC:SiO₂ =(9-11):(7.5-8.5), in the presence of sodium hydroxide. The initial mixture is crushed to a particle size of less than 200 microns, an aqueous solution of sodium hydroxide with a concentration of 120-160 kg/m³ is added until the ratio T:L = 1:(7.3-8.2) is obtained. Hydrothermal treatment is carried out at a temperature of 250-280°C and a pressure of 3.6-5.6 MPa for 1-3 hours with a stirring speed of 300-310 rpm. The pulp is cooled to a temperature of 55-60°C, filter, the resulting precipitate is washed with water and dried at a temperature of 50-60°C.

EFFECT: invention makes it possible to simplify the production of calcium silicate by eliminating the use of organic compounds and high temperatures.

1 cl, 1 dwg, 2 ex