Reductive removal of arsenic from waste acid containing high-acidity and arsenic levels through iodide and copper powder synergy

Large amounts of waste acids with high acidity and arsenic levels are produced during pyrometallurgy of nonferrous metal sulfide ores, in which the treatment of arsenic remains a problem. In this study, copper powder was used as a reducing agent and synergized with iodine ions to effectively remove arsenic from waste acids. The influences of stirring speed, copper powder particle size, sodium iodide/copper powder dosages, and reaction temperature on the removal efficiency of arsenic were investigated. The results showed almost complete removal of arsenic under the optimal conditions: 600 rpm stirring speed, copper powder particle size