We buy all types of catalytic converters including ceramic catalytic converters, diesel and DPF units, O2 sensors, loose catalyst and foils. The value in catalytic converters come from the rhodium, palladium and platinum that are found inside each catalytic converter, collectively referred to as the Platinum-Metals Group (PMGs). These precious metals convert harmful exhaust gasses such as carbon monoxide and nitrous oxide into water, nitrogen gas, and carbon dioxide.