Rapid Treatment and Reaction Mechanism of Complexation Plating Effluents by Molybdenum Disulfide/Copper Sulfide+Peroxosulfate Process

Abstract The removal of complexed heavy metals in complexation plating effluents is always a problem. Here molybdenum disulfide/copper sulfide (MoS 2 /CuS) composite was synthesized to activate peroxosulfate (PMS) to treat complexation nickel simulated plating effluents. MoS 2 /CuS showed excellent PMS activation effect. The removal efficiency of 50 ppm Ni‐EDTA by MoS 2 /CuS+PMS process and Ni‐citrate by MoS 2 /CuS process reached 99.7 % and 100 % for 20 min treatment, respectively. The excellent performance of MoS 2 /CuS+PMS process for heavy metal complexes removal is attributed to two ways: oxidative degradation and catalytic decomplexation. Oxidative degradation is to degrade complexing agent into small molecules through . SO 4 − produced by PMS activated directly by the synergy between MoS 2 , CuS and Ni‐EDTA. Catalytic decomplexation is to replace Ni 2+ in Ni‐EDTA by the metal active sites of MoS 2 /CuS to release Ni 2+ and remove it. These two degradation pathways make the MoS 2 /CuS+PMS process has excellent removal efficiency. In addition, the MoS 2 /CuS+PMS process eliminates the dependence of the Fenton reaction on iron‐based reagents and avoids the production of iron sludge precipitation. These findings provide new insights for the development of metal sulfide activating PMS to treat complexation plating effluents.