Promotion of Cu-SSZ-13 on Urea Decomposition

Based on the homemade flow reaction test platform, the thermolysis and hydrolysis process of urea and its byproducts on the Cu-SSZ-13 catalyst was studied, and the formation rule of gas-phase products in the thermolysis and hydrolysis process was systematically studied. The results show that Cu-SSZ-13 and H-SSZ-13 catalysts have a catalytic hydrolysis effect on urea as well as a slight catalytic thermolysis effect. The intermediate product isocyanate acid is mainly adsorbed on Si and Al active sites of Cu-SSZ-13, while the Cu active site does have an effect on the hydrolysis of HNCO. As a result, the overall decomposition of urea is improved by the Cu-SSZ-13 catalyst, especially at low temperature. Therefore, the Si/Al ratio of the Cu-SSZ-13 catalyst should be reasonably planned in order to make urea decompose completely and reduce the risk of urea deposition.

Automated summary

The study found that the Si/Al ratio of the Cu-SSZ-13 catalyst should be reasonably planned to enable complete urea decomposition and reduce the risk of urea deposition.