METHOD FOR REMOVING HEAVY METAL IONS FROM CONCENTRATED PROCESS SOLUTIONS AND WASTE WATER Russian patent published in 1997 - IPC

FIELD: waste water purification. SUBSTANCE: invention relates to purifying industrial waste water from heavy metal ions and galvanic production waste water. Predetermined volume of process solution or waste water with known concentration of heavy metal ions is treated with excess of ferric sulfate, then alkalized to pH 9-10 and, and into thus formed suspension, ferritization catalyst is introduced. Suspension is heated to 60-90 C and maintained at that temperature with simultaneous bubbling with compressed air to completion of ferritization process. Suspension is finally cooled and separated into liquid and solid phases by a known technique. As ferritization catalyst, alkali metal persulfates, permanganates or perchlorates are used, their quantity being 0.001- 0.002% based on ferric sulfate weight. Completion of ferritization process is judged of by minimum solubility of solid phase in excess of 0.0001 N sulfuric or hydrochloric acid. EFFECT: enhanced efficiency of process. 3 cl, 2 tbl