NOUFERROUS METALLURGICAL EQUIPMENT

To efficiently recover selenium (Se) and tellurium (Te) from the copper leaching solution generated by sulfation roasting of copper anode slime, this study aimed to shorten the Te extraction process, enhance Te recovery efficiency, and achieve one-step separation of Se and Te from the slime. A combined process integrating concentration enrichment, sodium sulfite reduction, and hydrochloric acid-catalyzed Te reduction was proposed for Se and Te recovery from the target leaching solution. Experimental results indicated that when the copper leaching solution was concentrated by 3 times, the direct recovery rate of copper reached 67.5%. For Se recovery, a high direct recovery rate of 97.45% was achieved under the optimal conditions: stirring speed of 150r/min, reduction temperature of 80℃, sodium sulfite addition multiple of 2.5, and reduction time of 2h. Regarding Te recovery, the optimal parameters were determined as stirring speed of 150r/min, reduction temperature of 90℃, hydrochloric acid addition multiple of 1.0, sodium sulfite addition multiple of 3, and reduction time of 2h, resulting in a direct recovery rate of 92.62%. In the scale-up experiment, the direct recovery rates of Se and Te were further improved to 98.86% and 93.72%, respectively. By leveraging the stepwise reduction strategy, this process enabled efficient and selective recovery of Se and Te from the copper leaching solution, providing technical support for the resource utilization of copper anode slime with remarkable economic and environmental benefits. Moreover, it offered an innovative approach for the one-step recovery of Se and Te from copper anode slime.