Mechanism of Propane Adsorption and the Following NO(x) Reduction over an In/BEA Catalyst: A Computational Study

[Image: see text] To expand the knowledge on hydrocarbon selective catalytic reduction (SCR) and follow the research steps of methane-SCR and propane-SCR in our previous work, we studied the characteristics of propane adsorption on In/BEA zeolite, explored the NO and NO(2) activation process on a propane adsorbed catalyst, and calculated the reaction enthalpy of two reaction pathways. Results showed that O site in the L-model (the [InO](+)/BEA structure) was the main active site in the adsorption process, and any of the carbon atoms in the propane molecule could react with it, with a lower adsorption energy than methane (−3.20 vs −2.98 eV). Also, NO or NO(2) could not be directly activated on the propane adsorbed catalyst, indicating that the process may be complicated. In addition, propane reduces the NO or NO(2) molecule with two different pathways and the final products were less stable than those of methane (−5.6 vs −20 eV). These results could explain the fact that propane and methane had different reaction temperatures and would further deepen our understanding of the propane-SCR process.