Donut Media’s video “Catalytic Converter: How It Works | Science Garage” covers catalytic converters using narration, simulations, and cutting a catalytic converter in half. Bart explains that catalytic converters are part of engine exhaust systems designed to reduce harmful emissions. They are needed because engines do not burn gasoline perfectly, resulting in harmful molecules leaving the engine, including carbon monoxide, hydrocarbons, and various nitrogen compounds.
Catalytic converters help with all three because they contain “catalysts” that “convert” harmful emissions into safer molecules or compounds. Catalytic converters include ceramic components that get hot and help rare metals such as platinum, palladium, and rhodium react with the emissions. In the reduction catalyst stage, platinum and rhodium pull oxygen off the nitrogen atoms, so the nitrogen leaves the exhaust as N2, which is found naturally in the atmosphere.
The oxidation stage sees platinum and palladium use oxygen to bind to carbon to generate carbon dioxide and oxidize unburnt hydrocarbons. He also makes the point that today’s vehicles are finely tuned and need catalytic converters to operate correctly. Bart also answers whether catalytic converters reduce engine horsepower and notes that some even increase horsepower. He also cuts open a catalytic converter to show its honeycomb chambers that help cut automotive emissions by more than 70%, dramatically reducing smog since adding these systems to motor vehicles.