PHOTOCATALYTIC DECOMPOSITION OF DINITROGEN OXIDE ON CU-CONTAINING ZSM-5 CATALYST

Photodecomposition of dinitrogen oxide (N2O) into N-2 and O-2, on Cu-e xchanged ZSM-5 zeolite (ion-exchange degree, 145%), degassed at 723 K, proceeds catalytically at 278 K. The dependence of the decomposition rate on the wavelength of the irradiated light reveals the importance of the excitation of monovalent Cu ions (<300 nm) in the photocatalyti c decomposition of N2O. The rate of decomposition can be expressed by the rate equation : [GRAPHICS] where a and b are constants, and a is p roportional to the light intensity. The desorption of O-2 from the sur face is not a rate-determining step in the photodecomposition or the t hermal decomposition of N2O on the zeolite which occurs with an appare nt activation energy of 37 +/- 3 kJ mol(-1).