Sustainable and effective extraction of Se and recovery of valuable metals from selenium filter residue by vacuum volatilization

Abstract

Selenium filter residue (SFR) is a high-value secondary resource generated during crude selenium purification. In this study, a new sustainable and efficient SFR treatment process is proposed, which not only enables the recovery of Se with high efficiency and purity but also effectively enriches valuable metals for the overall resource utilization of the entire process. The possibility of Se recovery during SFR was qualitatively analyzed using the saturated vapor pressure. A vacuum volatilization experiment was designed to investigate the recovery of Se and valuable metals at different temperatures (473–573 K) and holding times (30–120 min). The obtained results revealed that the purity of Se in volatiles reached 99.9 % at a temperature of 533 K and holding time of 90 min. The contents of valuable metals such as Te, Cu, Pb, Ag, and Au in the residue reached 4.16 %, 4.06 %, 11.49 %, 1.57 %, and 0.062 %, respectively, indicating their efficient enrichment and recovery. This work demonstrates that it is possible not only efficiently recover Se from the SFR but also maximize the enrichment of valuable metals and significantly increase the resource utilization efficiency, which satisfies the clean production requirements of the metallurgical industry.