Since the 1970s, the production of automotive exhaust purification catalysts has become a major user of platinum group metals (PJMs). In 2008, the world consumed 118.3 tons of Pt, 136.2 tons of Pd, and 23.6 tons of Rh in this field, accounting for 63.7%, 60%, and 110% of the mineral production that year, respectively. From 1975 to 2008, over a period of 33 years, the world cumulatively used 1836.3 tons of Pt, 1918 tons of Pd, and 365 tons of Rh in automotive exhaust purification catalysts, totaling 4119 tons, approximately 10 times the 2008 mineral production.
China’s consumption in this field has exceeded 100 tons, which is 50 to 60 times the annual production of Chinese mines. Based on a failure cycle of 5 to 7 years or 50 to 70 km of driving, the world needs to replace 100 to 200 million sets of failed catalysts annually, requiring the recycling of approximately 200 tons of PJMs, about half of the mineral resource production in 2010. It is estimated that in 4-5 years, China will need to replace approximately one-tenth of the world’s annual number of expired catalysts (0.1-0.2 billion sets), requiring the recycling of over 20 tons of platinum group metals.
Exhaust automotive exhaust catalysts are often referred to as “flowing platinum group metals,” and the recycling of platinum group metals from them will form a large-scale secondary resource recycling industry both domestically and internationally. This has become a global challenge for the technological and industrial development of this sector, attracting widespread and positive attention from the academic community.
