Mechanism of hydrogen spillover and its role in deuterium exchange on PtY zeolite

Abstract

The exchange of the surface hydroxyl groups of HNaY zeolite with D 2 takes place in the presence of platinum much faster than in the absence of platinum. To cause this effect it is sufficient to arrange the platinum at a distance of a few millimeters from the HNaY zeolite. The transport of the activated deuterium to the OH groups of the HNaY zeolite, i.e., its spillover, does not occur through the gas phase but on the surface of whatever solid is situated between the platinum and the HNaY zeolite. The transport of the activated deuterium takes place on oxide materials at the same rate, independent of their chemical nature, but it occurs only very slowly on the surface of stainless steel. It is proposed that the mechanism of spillover probably involves the participation of lattice oxygen of the solid surface.