Combinatorial computational chemistry approach to the design of catalysts

Combinatorial chemistry is an efficient technique for the synthesis and screening of a large number of compounds. Recently, we introduced the combinatorial approach to computational chemistry for a catalyst design and proposed a new method called "a combinatorial computational chemistry" [K. Yajima et al., Appl. Catal. A, in press.]. In the present study, we have applied this "combinatorial computational chemistry approach" to the design of deNO(X) catalysts. Various ion-exchanged ZSM-5 are good candidates as catalysts for removal of nitrogen oxides (NOX) from the exhaust gases in the presence of excess oxygen. Here we described the screening of the exchange cations in ion-exchanged ZSM-5 which are strong against poisons. In the deNOx reaction NO2 molecules play an important role in the formation of reaction intermediates with reductants. Here, we estimated adsorption energies of NO2 on various ion-exchanged ZSM-5 catalysts. The difference in the adsorption energies of NO2 and poisons such as water and SOX molecules has been compared. Cu+, Ag+, Au+, Fe2+, Co2+ and Cr3+-ZSM-5 were found to have a high resistance to water and SOX molecules during the deNO(X) reaction.