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How do catalytic converters convert harmful exhaust gases into less harmful substances?
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air pollution control
Even something as simple as breathing can get complicated.
In the context of air pollution control, a catalytic converter functions by using a catalyst—often composed of platinum, palladium, or rhodium—to promote chemical reactions that transform noxious exhaust gases into less harmful substances.123
The device consists of an insulated chamber containing a honeycomb structure or pellets coated with these catalysts, through which engine exhaust passes. The conversion process involves two primary chemical actions:13
- Oxidation: Hydrocarbons and carbon monoxide are oxidized to form water vapour and carbon dioxide.13
- Reduction: Nitrogen oxides are reduced to nitrogen and oxygen.13
By facilitating these reactions, the catalytic converter significantly limits the discharge of pollutants from internal-combustion engines into the atmosphere.12