Insight into Pyrometallurgical Recovery of Platinum Group Metals from Spent Industrial Catalyst: Co-disposal of Industrial Wastes

Considerable amounts of spent catalyst and metallurgical dust are posing a threat to the ecological environment and human health. Herein, sintering tailing dust (STD) has managed to capture platinum group metals (PGMs) from the spent volatile organic compound control catalyst (SVC) to obtain a Fe-PGM alloy in the pyrometallurgical process. More than 99% PGMs and 90% iron were recovered with a PGM enrichment coefficient around 4. A distribution ratio of 922 was achieved under the conditions of waste matrix (40% SVC:60% STD) and fluxing agents (20 wt % CaO, 12 wt % borax) at 1500 °C for 30 min. Combining DFT calculations with experimental results, the inevitable oxygen species showed a negative effect on PGM recovery, and the effect was more pronounced for platinum. Additionally, various crucial materials (>95 wt %) for industrial production could be separated from slag by stepwise treatment, and the cycling utilization of Na2CO3 would be achieved. Appreciable economic benefits might be profited via this proposed method, and no corrosive, volatile, or other additional solid wastes would be produced. This work is a case study for synergistic disposal of multiple solid wastes and upholds the concept of circular economy. It tries our best to pave the way to establishing a zero-waste society.