Welcome to Chemistry Connections, my name is Matthew Nguyen and I am your host for episode 15 called Fumes to Fresh Air. Today I will be discussing the chemistry of catalytic converters.

General Information on Catalytic Converters

• Used to reduce emissions from car engines
• Used in exhaust systems to remove harmless byproducts from internal combustion engines
• Removes nitrogen oxides, carbon monoxide, and hydrocarbons and turns them into carbon dioxide, water, and nitrogen gas
• Converts 98% of the harmful emissions to less harmful gasses
• Most stolen parts of the car because it has valuable materials like platinum, rhodium, and palladium which can sell for a lot of money
• No more than 4-9 grams of these precious metals are used in a single converter
• Located between the muffler and the engine
• Composed of metal housing with a ceramic honeycomb-like interior with insulating layers

1. To begin, I’ll first dive into what specifically a catalytic converter is and what its function is for those who don’t know
2. A catalytic converter filters out harmful emissions released by a vehicle.
3. It is a metal square box containing a ceramic honeycomb interior, located on the underside of the car between the engine and muffler with insulating layers composed of precious metals like platinum, rhodium, and palladium.
4. Because these metals are extremely valuable, they make the converter one of the most frequently stolen items in a car. Put a pin in that idea, we’ll come back to it later.
5. Due to the elements of palladium, platinum, and rhodium, a single converter can filter 98% of harmful emissions like nitrogen oxide, carbon monoxide, and hydrocarbons into harmless gasses of carbon dioxide and nitrogen.

The Chemistry part of Catalytic Converters

• One reduction and two oxidation reactions occur inside a catalytic converter
• Nitrogen oxide reduces into elemental nitrogen and oxygen
• Carbon monoxide oxidized into carbon dioxide