METATHESIS OF ACIDIC BY-PRODUCT OF CHLORINE DIOXIDE GENERATING PROCESS

摘要

Sodium sesquisulfate produced in crystalline form in a high acidity highlyefficient chlorine dioxide generating process(#12) as shown in the figure is converted by metathesis to crystallineanhydrous neutral sodium sulfate (#40) and the acid recoveredas a result is recycled (#44) to the chlorine dioxide generating step. Themetathesis (#32) is effected by contacting the crystallinesodium sesquisulfate with aqueous sodium chlorate solution (34) aqueouschloride solution, aqueous methanol or wateralone: The metathesis is effected in such manner as to minimize the additionalevaporative load imposed on the chlorine dioxidegenerating process by the metathesis medium: