Development of Control Technology for Acid Mine Drainage by Coating on the Surface of Pyrite using Chemicals

Acid mine drainage occurs when sulfide minerals are exposed to an oxidizing environment. The objective of this study was to inhibit the oxidation of pyrite by applying various coating agent such as KH2PO4, MgO and KMnO4 over its surface as an oxidation inhibitors. Experiments were conducted for 8 days to test the feasibility of oxidation inhibitors. The optimal condition of coating agent for standard pyrite and IK mine was the combination of 0.01M KH2PO4, 0.01M NaOAc and 0.01M NaClO. Otherwise, for YD mine the combination of 0.01M KMnO4, 0.01M NaOAc and 0.01M NaClO. The SO4����� reduction efficiency of pyrite, IK and YD mine samples was 70, 92 and 84%, respectively. For 8 days,no significant increase of SO4����� from pyrite sample coated with inhibitor was observed. The pH of solution remains in between 4 to 6 for the reaction conditions