What is a catalytic converter and how does it reduce emissions?

A catalytic converter is an emissions control device that uses precious metal catalysts (platinum, palladium, rhodium) to convert harmful exhaust gases into less harmful substances. It performs three main conversions: oxidizing carbon monoxide to carbon dioxide, oxidizing unburned hydrocarbons to water and CO2, and reducing nitrogen oxides to nitrogen gas. Three-way catalysts require operation near stoichiometric air-fuel ratio for optimal efficiency.