HYDROGEN-DEUTERIUM EXCHANGE CATALYZED BY CHROMIA-ALUMINA SOLID-SOLUTIONS

Alpha alumina, alpha chromia as well as ten corundum-phase chromia-alumina solid solutions have been studied as catalysts for hydrogen-deuterium exchange over the temperature range from 100 to 700 K. The adsorption of hydrogen has also been investigated. A general analysis of the coordinative unsaturation to be expected on the principal surface planes of the corundum structure is presented and local charge variations at multiplet sites are identified. The implications of introducing transition metal ions are then indicated. The catalytic results are shown to be consistent with this model and with the electronic interactions known to occur between chromium ions in chromia-alumina.