Patent ID: 6355223
Filing Date: 2002-03-12
Classification: C01B,Y02P

Abstract:
A continuous process for the production of Cl2 from HCl, said process comprising the steps of:(a) reacting HCl with an aqueous oxidizing mixture comprising nitric acid and sulfuric acid, so as to produce Cl2 in a stream comprising nitrogen-containing species, sulfuric acid and water; (b) oxidizing at least a portion of the nitrogen-contain species so as to form nitric acid in the stream; (c) removing water created in step (a) from said stream, wherein the step of removing water is carried out in a super-azeotropic acid reconcentration system and comprises the steps of: (i) delivering said stream to a distillation column; (ii) introducing sulfuric acid into said column; (iii) drawing off nitric acid from said distillation column; (iv) drawing off a mixture of sulfuric acid and water at the bottom of said distillation column and delivering the mixture to a flash evaporator; and (v) drawing off reconcentrated sulfuric acid from said flash evaporator.