More Platinum Metals in Catalytic Converters Needed to Meet New Emission Standards

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Catalytic converters must work more efficiently to further limit pollutant emissions from cars. This requires more platinum, palladium and rhodium in the filter.

The EU is preparing to further tighten exhaust emission limits for combustion engines. The new Euro 7 standard, scheduled for introduction in 2025 according to a press release, is intended to further reduce pollutant emissions from passenger cars and light commercial vehicles. In addition to lowering particulate emissions, the focus is also on reducing nitrogen oxide emissions: cars are to emit 35% less of this, while trucks are to see a reduction of 56%.

New Combustion Engine Regulations Worldwide

In other parts of the world, the automotive industry is also facing stricter legislation on exhaust emissions. China, for example, will tighten climate requirements for light vehicles from mid-2023 with the China 6b emissions standard . Also, in 2023, the USA plans to adopt tougher emissions regulations for heavy-duty vehicles with EPA 27 . Brazil will further regulate existing emissions standards from 2025 with PROCONVE L-8 .

Fewer Exhaust Gases through Improved Filtering

Catalytic converters are crucial for filtering exhaust gases. They convert harmful carbon monoxide into carbon dioxide and filter out nitrogen oxides and hydrocarbons. The chemical processes required for this are carried out by the three precious metals platinum, palladium and rhodium, among others. Depending on the catalyst, three to five grams of these are used as a coating in a ceramic filter. The new emission limits require an increase in the precious metal portion. The higher the precious metal content in the filter, the more efficient the exhaust gas purification. Although the increase in precious metals in the catalytic converter will only amount to a few milligrams per unit, it could add up to several tons in the mass of cars produced worldwide.

Rhodium and Palladium as Coveted Raw Materials

The automotive industry already uses 31 metric tons of rhodium per year for exhaust filters, more than is primarily mined. As a by-product of platinum and palladium extraction, mining supplies the market with 25 tons of the metal annually. Another ten tons are added via recycling. In the case of palladium, the automotive industry is also the largest customer. Over 80 percent of the approximately 310 metric tons available each year, comprising 220 metric tons mined and 90 metric tons recycled, are used in the production of catalytic converters. Given the stricter emission limits, the trend is upward. Stronger demand could drive the already high prices even higher.

In the case of the Euro 7 standard, buyers of cars with the new catalytic converters are likely to face additional costs. According to initial estimations, the regulation-related adjustments, which include the increase in the platinum metal content in the catalytic converters, will increase the purchase price by up to 150 euros per car and 2600 euros per truck.