METHOD OF CLEANING GAS FROM SULFUR DIOXIDE Russian patent published in 1997 - IPC

FIELD: gas purification. SUBSTANCE: sulfur dioxide-containing gas and reducing gas such as carbon monoxide, hydrogen, hydrogen sulfide, carbon oxysulfide taken either separately or as a mixture are passed through contact mass bed containing FeS or Cu₂S on carrier at 180-420 C and pressure 100-800 mm Hg. During this operation, sulfur dioxide is reduced to vaporous sulfur that is selectively and irreversibly combined with FeS or Cu₂S to form FeS₂ or CuS. Reduction terminated, contact mass is heated to 450-700 C to remove free sulfur by way of aspiration or blowing with inert gas such as nitrogen at pressure 100-800 mm Hg. Removed sulfur is cooled and delivered to consumers, whereas contact mass containing FeS or Cu₂S is reutilized for reduction of sulfur dioxide. All operations are accomplished in alternate mode in the same reaction space.. EFFECT: enhanced efficiency of gas purification process. 2 cl