Trends of Technological Development of Platinum Group Metal Recycling: Solubilization and Physical Concentration Processes

Spent automobile catalysts are the most important secondary resource for platinum group metals (PGMs), and their recycling is essential not only to ensure a steady supply of PGMs but also to preserve the natural environment. However, several factors limit the efficiency of PGM recovery in current recycling processes. Specifically, PGMs represent a small proportion of the entire catalyst and are difficult to dissolve in aqueous solutions for subsequent separation. In recent decades, multiple technologies have been developed to make the recycling of PGMs more efficient and environmentally-friendly. Herein, we introduce the typical industrial processes for recovering PGMs from spent catalysts, along with established and emerging trends in the technological development of PGM recycling. Furthermore, we review novel recycling techniques for converting PGMs in spent catalysts into more soluble states and/or physically concentrating PGMs from spent catalysts.

Automated summary

Spent automobile catalysts, the most important secondary resource for platinum group metals (PGMs), need to be recycled in order to ensure a steady supply of PGMs and protect the environment. However, current recycling processes face challenges in efficient PGM recovery due to the small proportion of PGMs in the catalyst and their difficulty in dissolving in solutions. Various technologies have been developed to improve the efficiency and environmental-friendliness of PGM recycling. This article introduces industrial processes for PGM recovery from spent catalysts and discusses established and emerging trends in PGM recycling technology, including novel techniques for converting PGMs into more soluble states and physically concentrating them from spent catalysts.