SOLID-STATE INTERACTION BETWEEN NAY ZEOLITE AND VANADIUM PENTOXIDE, MOLYBDENUM TRIOXIDE, OR TUNGSTEN TRIOXIDE

When mixtures of NaY zeolite with V2O5 or MoO3 are calcined in air at atmospheric pressure within well-defined temperature and composition r anges, the oxides migrate into the pores of the zeolite lattice. In co ntrast to these oxides, WO3 does not diffuse into the pores of NaY aft er treatment under the same conditions. The differences in the behavio r of each of these oxides with NaY are related to their dissimilar phy sical properties (melting point and solubility in hot water). Beyond c ertain temperature and oxide concentrations, the NaY lattice is destro yed and new phases are formed. These interactions and reactions in the solid state have been followed by X-ray diffraction and Si-29 n.m.r. and Xe-129 n.m.r. of adsorbed xenon.