Three-way catalysts are devices that clean gasoline emissions by a process of deoxidizing and oxidizing gasoline automotive emission gas. They are installed in a car's exhaust system and break down toxic components contained in automobile exhaust into water, carbon dioxide and nitrogen using a platinum-based catalytic converter.
Automotive catalyst uses elements of the platinum group as active agents.
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Platinum group catalysts tend to be stable in environments where there is a rapid transition from low to very high temperatures approaching 1000 degrees |
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These catalysts perform their functions and hold up in extreme environments such as those present in the internal combustion engine. |
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They are generally physiologically and biologically benign. |
- Rh shows high activity in purification of above three components even in small amounts.
- Pd has superior purification characteristics compared to Pt, although Pt has been traditionally used more commonly than Pd.
Subcatalysts have enhance effectiveness, durability and other properties when they are added to the main component of a catalyst even in small amounts.
- OSC absorbs more oxygen at high levels of oxygen.
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oxygen in automotive emission gas
- OSC absorbs more oxygen at low levels of oxygen
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oxygen in automotive emission gas
