Effectiveness of microwave-assisted thermal treatment in the extraction of gold in cyanide tailings.

A new technology for treating cyanide tailings (CT) by microwave chlorination roasting was first proposed in this study. A green process with prospective environmental and economic significance was experimentally and theoretically established for the sustainable extraction of gold from CT. The microwave roasting behavior and trajectory of gold in different gold-bearing bodies under microwave-enhanced roasting and conventional roasting conditions were explored and compared by introducing the concept of thermal and non-thermal effects provided by the microwave field. At the same time, the superiority of microwave chlorination roasting was verified by a series of experiments. Under the same conditions of the roasting experiments, the energy consumption of conventional calcination was more than double greater than that of microwave roasting. Finally, the essence of microwave chlorination roasting in the treatment of CT was summarized as a non-polluting process.