Method of recovering thiourea dioxide

摘要

According to this invention there is provided a method of recovering thiourea dioxide characterized in that in the production of thiourea dioxide by the reaction of thiourea and hydrogen peroxide in an aqueous solvent, the waste liquor after separation of the crystals of thiourea dioxide after reaction is treated with an ion-exchange resin to remove side reaction products and impurities contained therein, and is then concentrated with a reverse-osmotic membrane to crystallize the thiourea dioxide dissolved therein.