The rare earths used in the exhaust gas purification catalyst are mainly a mixture of cerium oxide, oxidation fault and lanthanum oxide, of which cerium oxide is the key ingredient. Due to the redox characteristics of cerium oxide, the components of the exhaust gas can be better controlled, and oxygen can be supplied in the reducing atmosphere or oxygen consumed in the oxidizing atmosphere. At the same time, the addition of rare earth components to the active components of the catalyst can improve the resistance to lead and sulfur poisoning, the stability of high temperature resistance, and the working characteristics of the air-fuel ratio of the catalyst. Finally, rare earth catalysts have the following characteristics:
1. Improve the thermal stability and mechanical strength of the catalyst
2. Increase the activity and oxygen storage capacity of the catalyst
3. Increase the anti-poisoning ability of the catalyst
4. It has the effect of a three-way catalyst
2. Research and application of rare earth in industrial waste gas and human settlements purification
At present, the use of rare earth catalytic technology to treat industrial waste gas and human settlements is mainly focused on volatile organic waste gas treatment, flue gas desulfurization and denitrification, photocatalytic air purification and coking sewage catalytic purification.
China is rich in rare earth resources, and rare earth materials are cost-effective, reusable, no secondary pollution to the environment, are environmentally friendly materials, and their development and application are of great significance to the sustainable development of the environment and economy. At the same time, as a unique catalytic functional component or an important co-catalyst, rare earth plays an important role in a variety of catalytic materials by virtue of its catalytic performance and good anti-poisoning ability, and also provides conditions for the transformation of various catalysts to industrialization.