Abstract: To facilitate the resource utilization and safe disposal of arsenic-bearing solid waste,this study investigates the
removal of arsenic from tin tailings using a synergistic process combining ball milling and hydrometallurgy. A thermodynamic equilibrium analysis was conducted on the SiO₂-As₂S₃-CaCO₃-FeS₂-H⁺ / OH^- -H₂O system to elucidate the leaching mechanism
and dissolution equilibrium of arsenic. The effects of key process parameters,including material-to-ball ratio,material-to-water ratio,milling time,and pH value,on arsenic leaching efficiency were systematically examined,and the experimental conditions were optimized. The results show that decreasing the material-to-ball ratio and material-to-water ratio,as well as extending the milling time,enhance arsenic leaching. pH value significantly influences arsenic dissolution behavior,with the leaching rate reaching 84. 6% under strong alkaline conditions (pH=11. 0). Phase and microstructural analyses reveal that ball milling introduces structural defects on particle surfaces,reducing the average particle size and increasing the specific surface area of the tailings,thereby significantly promoting interfacial mass transfer and arsenic leaching. This study provides a technically feasible and readily industrializable approach for the green separation of arsenic from typical arsenic-bearing tin tailings.