A review on management of waste three-way catalysts and strategies for recovery of platinum group metals from them

Platinum group metals (PGMs), especially platinum (Pt), palladium (Pd), and rhodium (Rh), are widely used in automotive three-way catalysts (TWCs). PGM resources are scarce and unevenly distributed, with global reserves of 69,000 t in 2020, of which more than 99% are concentrated in South Africa, Russia, Zambia, and the United States. However, the demand for PGMs worldwide is growing continually, especially in China. The recovery of PGMs from spent TWCs not only can alleviate the contradiction between supply and demand but also have good economic and environmental benefits. This paper briefly analyzes the market demand for Pt, Pd, and Rh in the global automotive industry in recent years, emphasizing the importance of waste TWC recycling. It also presents the current status of waste TWC management in some countries, especially China, and critically reviews the main recycling strategies for waste TWCs. On this basis, suggestions for strengthening the management of waste TWCs in China are put forward, and the future development trend of recycling technology is foreseen. The purpose of this paper is to provide some valuable references for the decision-makers of waste TWC management, and hopefully to provide inspiration for related scholars on the future research direction of waste TWC recycling technology.