A Novel Process for the Treatment of Copper-Smelting Waste Acid with a High Arsenic Concentration

Abstract

A novel process was proposed for the separation of Cu and As from Cu-smelting waste acid (CSWA). This process includes three steps, namely, the oxidization of As via the addition of H2O2, the selective separation of Cu through the use of Na2S, and the removal of As via the synthesis of scorodite. The CSWA was initially oxidized using H2O2 where the As(III) transformed into As(V). The oxidization of As(III) is believed to be the decisive step with regard to the selective separation of Cu and As via the sulfide precipitation process. The results showed that 99.4% of the Cu and 1.8% of the As were precipitated via the sulfidization process and that 98.8% of the As in the Cu-removed CSWA was removed in the form of scorodite (FeAsO4·2H2O). This novel process exhibits promising application prospects for the treatment of CSWA.