How catalytic converters clean exhaust
Transcript
Inside the converter, exhaust is guided through a ceramic or metal honeycomb, which gives the gases a huge surface area to touch without creating much resistance.<sup class="text_citation" source_id="8"></sup><sup class="text_citation" source_id="18"></sup>
That honeycomb is coated with precious-metal catalysts such as platinum, palladium, and rhodium, which speed up reactions without being used up.<sup class="text_citation" source_id="7"></sup><sup class="text_citation" source_id="24"></sup><sup class="text_citation" source_id="34"></sup>
On those surfaces, carbon monoxide becomes carbon dioxide, nitrogen oxides are reduced to nitrogen and oxygen, and hydrocarbons are oxidized into carbon dioxide and water vapor.<sup class="text_citation" source_id="20"></sup><sup class="text_citation" source_id="33"></sup><sup class="text_citation" source_id="46"></sup>
But the converter works best when hot, usually around 400 to 800 degrees Celsius, because the reactions are too slow when it is cold, especially just after start-up.<sup class="text_citation" source_id="11"></sup><sup class="text_citation" source_id="12"></sup><sup class="text_citation" source_id="45"></sup>
Sources
- Reactions and catalysts - Chemical reactions - 3rd level Science Revision
- How do catalytic converters work?
- Why Does a Catalytic Converter Need to Reach a High Temperature to Function Effectively? → Learn
- Why Is the Operating Temperature of a Catalytic Converter Critical for Its Efficiency? → Learn
- Catalytic converters like it hot
- Catalytic Converter Honeycomb Structure Purpose | Mid-West
- 7.1: Catalytic Converters
- Catalytic Converter ensuring 90% Carbon Emissions’ Reduction
- What Is a Catalytic Converter and What Does It Do? | UTI
- Catalytic Converter: Emissions and Efficiency
- Structure of s
Let's look at alternatives:
- Modify the query.
- Start a new thread.
- Remove sources (if manually added).