Catalytic performance of Ag(x)/ZSM-5 catalysts for selective catalytic reduction of nitric oxide by methane

Ag(x)/ZSM-5 (x=3, 6, 9) catalysts for selective catalytic reduction of nitric oxide by methane (CH₄-SCR) were prepared by impregnation method. The physicochemical properties of the catalysts were characterized by XRD, SEM, NH₃-TPD, Py-FTIR, XPS and NO-TPD. The catalytic performance for selective catalytic reduction of nitric oxide by methane was evaluated in a fixed-bed micro-reactor under atmospheric pressure and the influence of Ag loading were investigated.The results show that the impregnation of Ag has changed the acidity and amount of acid of the catalyst and improved the adsorption and desorption performance of NO on ZSM-5 molecular sieve. With the increase of Ag loading, Ag particle size increases and results in higher methane activation as well as the denitration activity of CH₄-SCR over Ag(x)/ZSM-5 catalyst. Ag(9)/ZSM-5 has better denitration activity and the NO conversion is 41.87% at 350℃.