The Effect of Exchanged Cocation in Zeolite Cu, Me-ZSM-5

The effect of the second exchanged ions(Meⁿ⁺) in the zeolite catalysts Cu,Me-ZSM-5 has been investigated for the reaction of NO decomposition. The characteristics of the catalysts have been measured by means of XRD,EXAFS,and O₂-TPD-MS techniques.The local structure of copper in zeolite changes evidently because of the presence of cocations.It induces the change of copper reducibility and O₂ desorption property. The cocations such as Mg²⁺,Co³⁺, which enchance catalytiC activity of copper for NO decomposition, increase the coordination numbers and distance of Cu-O, and the ability of O₂ desorption enchances largely. However,the effect of ions such as K⁺, which decrease catalytic activity,is reversed. The extant of effect is consistent with its change of catulytic activity.All the results demonstrate that zeolite catalyst could be adjusted by exchanged cocations.