SEPARATING AND REUSING METHOD FOR CR(VI) ION IN ELECTROLYTIC SOLUTION FOR MANUFACTURING CHLORATE

摘要

PURPOSE:To recover and reuse Cr+6 ion by feeding an electrolytic soln. having a predetermined pH value for manufacturing chlorate to a tower packed with an anion exchange resin to obtain a chlorate soln. freed of Cr+6 ion and eluting Cr+6 ion with an aqueous soln. of alkali metallic hydroxide as a regenerating agent. CONSTITUTION:An electrolytic soln. contg. alkali metallic chlorate, alkali metallic chloride and Cr+6 ion for manufacturing chlorate is adjusted to 1-5pH and fed to a tower packed with an anion exchange resin to obtain a chlorate soln. freed of Cr+6 ion. A 0.05-1.0mol/l aqueous soln. of alkali metallic hydroxide contg. 1.0- 5.0mol/l alkali metallic chloride and 0.1-5.0mol/l alkali metallic chlorate is then fed to the tower to elute Cr+6 ion from the Cr+6 adsorbed anion exchange resin, and resulting aqueous soln. of alkali metallic hydroxide contg. Cr+6 ion is neutralized and reused in an electrolytic process for manufacturing chlorate. Since no Cr+6 ion is discharged from the system, environmental pollution can be prevented.