This paper examined the effects of sodium hypochlorite,hydrogen peroxide and sodium persulfate on the pre-oxidation treatment of pyrite.The study analyzed the dissolution characteristics of pyrite,cyanide consumption,thiocyanate ion concentration and the surface composition of oxidized residues resulting from treatment with various oxidants.The results indicate that all three oxidants inhibit cyanide dissolution of pyrite.When the sodium persulfate is used as the oxidant,the cyanide consumption is reduced by 51.72%,the thiocyanate ion generation decreases by 75.97%,and the oxygen environment in the cyanide leaching system is improved.In contrast,using sodium hypochlorite as an oxidant releases chloride ions,which increase cyanide consumption by 10.34%.SEM-EDS and XPS analyses results reveal that the application of oxidants results in the formation of FeO,FeSO4 and Fe2(SO4)3 on the pyrite surface.These compounds are non-reactive with cyanide,thereby inhibiting pyrite cyanidation and improving the leaching environment in the cyanide gold extraction system.
pyritecyanide leachingoxidizing agentsolution chemistryinterface physical and chemical properties