Patent ID: 6585950
Filing Date: 2003-07-01
Classification: C01B

Abstract:
A process of producing chlorine dioxide comprising the steps of reducing chlorate ions in an acid reaction medium maintained in a reaction zone of a chlorine dioxide generator, which reaction medium contains alkali metal ions and sulfate ions, thereby forming chlorine dioxide and a solid salt of acidic alkali metal sulfate, separating said solid acidic alkali metal sulfate from the reaction medium, contacting said solid acidic alkali metal sulfate with an aqueous medium in a mixing tank to effect at least partial conversion to neutral solid alkali metal sulfate, separating the at least partially neutralized solid alkali metal sulfate from the aqueous medium on a rotary drum filter operating with vacuum inside and with part of the drum submerged in a slurry of the at least partially neutralized solid alkali metal sulfate and the aqueous medium, forming an acid filtrate and feeding at least a portion of the acid filtrate to the mixing tank.