Catalytic Converter
An emissions-control device fitted to a vehicle's exhaust system. Platinum and palladium oxidize leftover hydrocarbons and carbon monoxide inside it, while rhodium reduces nitrogen oxides, before the cleaned exhaust reaches the tailpipe.
Covered in 4 MetalsCost.com News Intelligence articles, most recently on September 14, 2026.
Overview
A catalytic converter is a stainless-steel canister bolted into a vehicle's exhaust system, packed with a ceramic honeycomb substrate coated in a porous alumina washcoat that carries a thin dispersion of platinum-group metals. As hot exhaust gas passes through the honeycomb's thousands of narrow channels, the PGM coating catalyzes three reactions simultaneously — hence "three-way catalyst" — oxidizing carbon monoxide and unburned hydrocarbons into CO2 and water, while reducing nitrogen oxides back into harmless nitrogen and oxygen.
How It Works
Platinum and palladium do most of the oxidation work, converting CO and hydrocarbons; rhodium is the metal best suited to the reduction side, breaking down NOx — which is why rhodium, despite being used in the smallest quantity, is typically the most valuable metal in the unit. A gasoline converter carries roughly 10-15 grams of PGMs in total, split unevenly across the three metals; loadings have generally risen over time as regulations like Euro 6/7 and Bharat Stage VI tightened allowable tailpipe emissions.
Sources
- PGM loading and role of each metal in a catalytic converter — Understanding Precious Metals in Catalytic Converters (2026)
Coverage
BMI Cuts Platinum and Palladium Price Forecasts as Car Sales Slow and South African Mines Recover
BMI cut its 2026 platinum forecast to $1,900/oz from $2,000 and palladium to $1,400 from $1,500, citing shrinking car sales and faster South African mine recovery, though it still expects both metals in deficit.
Palladium Price Jumps Nearly 5% as Montana Miners Strike Over Health Benefits
Palladium jumped nearly 5% to $1,441 an ounce on September 3, 2026, after 420 United Steelworkers struck Sibanye-Stillwater's Stillwater East mine and Columbus refinery in Montana over a stalled health-benefits contract.
Impala Platinum's Annual Profit Surges More Than 30-Fold as Platinum and Palladium Prices Rally
Impala Platinum's FY2026 headline earnings rose more than 30-fold to R22.9 billion as platinum, palladium and rhodium prices surged, funding an elevenfold jump in shareholder dividends.
What Platinum, Palladium and Rhodium Are Actually Used For, Beyond Jewellery
Platinum, palladium and rhodium belong to a six-metal family prized for corrosion resistance and catalytic power. Here is what each is actually used for, from catalytic converters to dental alloys and industrial nitric acid production.
