METHOD OF PRODUCING CHLORINE BY CATALYTIC OXIDATION OF HYDROGEN CHLORIDE AND METHOD OF PRODUCING ISOCYANATES Russian patent published in 2013 - IPC C01B7/04 C07C263/10 

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. When producing chlorine by catalytic oxidation of hydrogen chloride, the hydrogen chloride stream used has content of elementary sulphur of less than 100 ppm, preferably less than 50 ppm, more preferably less than 5 ppm and even more preferably less than 1 ppm with respect to the mass of the hydrogen chloride stream. To obtain isocyanates by phosgenation of corresponding amines, a) carbon oxide is reacted with chlorine to obtain phosgene, b) the amines are reacted with phosgene to obtain isocyanates, c) the crude mixture of isocyanates is purified by distillation, d) the mixture of isocyanates and unevaporated residue obtained at step (c) is fed for isocyanate regeneration by evaporation or amine is regenerated by hydrolysis of the residue, and the regenerated isocyanate or regenerated amine is at least partially returned for reaction to step (b), e) chlorine is obtained by catalytic oxidation from the gas stream obtained at step (b), which contains hydrogen chloride, f) chlorine obtained at step (e) is at least partially returned to step (a) to obtain phosgene.

EFFECT: invention increases chlorine purity by reducing content of sulphur in hydrogen chloride used for production thereof.

10 cl, 1 dwg, 1 tbl, 3 ex