SODIUM HYDROSULFIDE PRODUCTION PROCESS Russian patent published in 2006 - IPC C01B17/32 

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention is directed to production of sodium hydrosulfide, which is widely used as reducing agent in chemical processes, as corrosion inhibitor in production of soda ash and sodium bicarbonate, for production of polysulfide plastics, in paper-and-pulp industry, mining, and leather industry. Process comprises reaction of sodium hydroxide with hydrogen sulfide, wherein hydrogen sulfide source is gas obtained during decomposition of barium sulfide by treating barium sulfide pulp containing 30% BaS with sulfuric acid atBaS/H₂SO₄ ratio 1.0:(1.0-1.2). Thus obtained barium sulfate is separated from liquid phase by filtration, whereupon barium sulfate is subjected to reductive firing at 900-1200°C to produce barium sulfide melt, which is leached with water to produce barium sulfide pulp. The latter is returned into sulfuric acid treatment stage.

EFFECT: reduced expenses on raw material, lowered explosion risk, and avoided use of expensive catalysts.

5 cl, 2 tbl, 4 ex