Electrochemical oxidation of sulfide in alkaline solution for odor gas treatment

This research studied the process of sulfide electrochemical oxidation with RuO2/Ti plate anode and single cell reactor.The effects of current density,initial concentration of sulfide,supporting electrolyte and solution pH on the removal rate of sulfide were investigated specifically.The results showed that the removal rate of S2 was over 95% at current density of 25mA/cm2 and initial sulfide concentration of 23 mmol/L.About 95% oxidization product of S2 was SO42,and other products included 2% — 3% sulfur,small amounts of SO32 and S2O32.The removal rate of S2 was mainly affected by the S2 concentration and the removal rate increased with the increase of current density.The pH value of electrolyte affected the reactions of Sx2.Strong base conditions could avoid sulfur deposition on the surface of anode.Adding electrolytes could improve the rate and depth of electrochemical oxidation.Compared with NaCl or other auxiliary electrolytes,NaOH could reduce the process time by 40% when the removal rate of S2 was 90%.