Oxygen isotope exchange on palladium catalysts

Oxygen heteromolecular isotope exchange on unreduced palladium catalysts, distingushing by metal content is studied. Content of 18O in gaseous phase is eoual to 46%. Calculations of heteroexchange rates are conducted with decrease of the 18O in the gaseous phase over solid sample. Method of oxygen thermodesorption has been used to establish that palladium, deposited on γ-Al2O3 during exchange process is in oxidized state; in this case strength of Pd-O bond is determined by content dispersity) of the metal. It is shown that significant increase of exchange rate on the samples with Pd >> 0.5 mass.% content can be induced as by side decomposition reaction of its oxide and corresponding dilution of gaseous mixture by ''light'' oxygen so by possibility of exchange with oxygen of PdO phase