Abstract

Large quantities of arsenic-containing toxic emissions are released during the smelting process of non-ferrous minerals. The scrubbing process of flue gases from roasting furnaces, for example, produces a large amount of arsenic-containing acid sewage, and the latter, in turn, produces arsenic sulfide slag during the sulfide precipitation process. The arsenic sulfide slag is highly toxic and cannot be disposed of directly to the environment. It needs to be converted to some environment-friendly forms before disposal. With increasingly stringent requirements on environmental protection, more attention is being paid to the eco-friendly treatment of arsenic waste. The oxidation of arsenic sulfide slag can be the appropriate process. In the present paper, methods for treating arsenic sulfide residue waste are suggested; these include ferric sulfate oxidation leaching, hydrothermal treatment assisted by ferric nitrate, alkali leaching with air oxidation, sodium carbonate alkaline leaching, hydrogen peroxide oxidation leaching, etc. The possibilities of suggested processes in the industrial environment are also discussed.

Keywords: Arsenic sulfide slag; Trivalent arsenic oxidation; Arsenic removal