Evaluation of a green-sustainable industrialized cleaner utilization for refractory cyanide tailings containing sulfur

In order to achieve the clean treatment of refractory cyanide tailings containing sulfur, a novel microwave-assisted chlorination thermal treatment recovery technology was proposed in this paper. On the basis of studying the mineralogy of cyanide tailings, the treatment capacity of common chlorinated agents for refractory cyanide tailings containing sulfur was compared. CaCl2 as the best chlorination agent, gold recovery and chlorine removal rates were 85.2% and 95%, under the optimal conditions. The specific action mechanism of CaCl2 in the process of microwave roasting was studied. Under the action of microwave, CaCl2 accelerated decomposition into chlorine-containing gas and rapidly diffused in cracks caused by thermal stress to ensure gold volatilization and chlorination. Finally, the approach and mechanism of removing residual harmful substances in roasting slag were proposed based on the environmental assessment of roasting slag. Environmental pollution and corrosion of building materials can be effectively avoided in the later transportation and secondary utilization of roasting slag. [Display omitted] •This study proposes a cleaner chlorine for a novel microwave-assisted recycling gold process.•Gold recovery and chlorine removal rates were 85.2% and 95% by using CaCl2.•Microwave roasting slag is obviously harmless and reduce the cost of post-treatment.