THE DESORPTION OF O-2 DURING NO AND N2O DECOMPOSITION ON CU-ZEOLITES AND FE-ZEOLITES

The decomposition of NO and of N2O over a CuZSM-5 zeolite and a Fe-mor denite, respectively, has been studied using tracer techniques. The re sults demonstrate the high mobility of the lattice oxygen ions in self -diffusion. They afford a possible explanation for the problem of how two extralattice oxygens located at positions remote from each other m ay combine to form the O-2 molecules which are spontaneously desorbed in these redox reactions. They show that a portion of the lattice oxyg en mixes into the O-2 released on decomposition. The data also show th at (NO)-O-18 and (N2O)-O-18 undergo exchange with the catalyst oxygen under reaction conditions.