Catalytic decomposition of nitrous oxide over Fe-BEA zeolites: Essential components of iron active sites

Abstract

The catalytic decomposition of N2O was investigated over Fe-BEA zeolites treated with various methods such as reduction, steaming and dissolution with potassium nitrate and nitric acid solutions in order to deduce the essen- tial components of the active sites for the decomposition. The iron species were characterized by XPS, XANES, ESR, NO adsorption, and linear sweep voltammetry. The reduction-treated Fe-BEA zeolite with the large amounts of Fe(II) and Fe(III) species showed the highest activity. On the contrary, the dissolution treatment with the potassium nitrate solution seriously deteriorated the catalytic activity of the Fe-BEA zeolite by agglomerating iron oxide clusters and interaction between iron and potassium atoms. The catalytic roles of Fe(II)/Fe(III) species and the negative effect of potassium on the catalytic activity of the Fe-BEA zeolites were discussed.