What catalytic material is typically incorporated inside automobile catalytic converters to facilitate the complete oxidation of carbon monoxide, unburned hydrocarbons, and nitrogen oxides__________________?
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Answer: B. Platinum
Explanation
Automobile catalytic converters incorporate platinum to catalyze complete exhaust gas oxidation. Precious metal catalysts accelerate reactions that convert carbon monoxide into carbon dioxide. Platinum helps eliminate harmful unburned hydrocarbons and nitrogen oxides from vehicle emissions. Platinum, palladium, and rhodium serve as the active catalytic metals in modern converters. Ceramic honeycomb structures coated with washcoat maximize the surface area for gas contact. High exhaust temperatures activate the catalyst to promote rapid chemical pollutant conversion.
Environmental regulations mandate catalytic converters on internal combustion vehicles worldwide. Automotive engineering designs ensure exhaust temperatures reach light off levels quickly. Proper catalyst maintenance prevents excessive smog formation and urban air pollution. Alumina acts as a porous support material rather than the primary active catalytic metal. Vanadium pentoxide is used in stationary industrial selective catalytic reduction units instead. Iron oxide serves as a catalyst in different industrial processes like ammonia production.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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