Even if cars are very convenient and necessary for everyday life, the total rates of air pollution they emit make it very disadvantageous for the environment. Thanks to devices known as catalytic converters, car emissions are controlled and the amount of chemicals released is reduced.
1. In internal combustion engines, a mixture of air and fuel. When the spark plug fires, the mixture produces combustion and is used to power the vehicle. The remains of the process exit through the valves and the process continues thousands of times. Some of the unused fuel in the form of hydrocarbons and carbon monoxide, as well as nitrogen oxide, will leak out of the car and pollute the air.
2. The catalytic converter’s job is to clean up engine emissions and make them safer and less dangerous to people and the environment. Through a chemical reaction, and a certain amount of energy, the catalyst transforms some of these gases and the results are much more favorable.
3. Catalytic converters need to change the harmful by-products of combustion through the oxidation process. The introduction of oxygen into the heated gases will cause the HC and CO to convert to water and carbon dioxide, which are in a sense less harmful. The catalyst has a thin layer of platinum and the coating is applied onto a substrate material such as a ceramic or metal honeycomb. The tiny platinum atoms hold the molecules together briefly. Oxygen is introduced and the catalyst works.
4. There are several types of catalytic converters. One of them is the bidirectional converter that performs the above process. This has been in cars since 1975. To address the third by-product, which is NOx, three-way converters are developed with an additional step known as turndown. This will split the NOx into nitrogen and oxygen. This is a challenge, but it has been solved by introducing the oxygen between the reduction and oxidation stage to make it more efficient.
5. A drawback of catalytic converters is that they require a certain temperature to meet the demands of the chemical reaction. This means that it will not work in the first few minutes after power on. If there is overheating, it will not work either. Other issues would be road temperatures and debris that could damage the converters.