Oxidation of CO and hydrocarbons over perovskite-type complex oxides

The catalytic activity of perovskites (MMO3)-M-I-O-II(MI = La; M-II = Co, M n, Cr, Al, Ni, and V) and (MCoO3)-Co-I (M = Y, Nd, Sm, and Er) in the oxida tion of CO, propylene, and ethylbenzene was investigated. The highest activ ity was observed for the (MCoO3)-Co-I catalysts with perfect perovskite str ucture. The nature of the rare-earth element has no influence on the cataly tic activity. Deformation of the octahedral coordination of the metal was f ound for the less active catalysts. The interaction of gases (CO, CO+air) w ith the catalyst surface was investigated. The more active catalysts adsorb a greater amount of O-2, and the adsorption occurs in the temperature regi on of the oxidation reaction. The activities of the perovskite- and spinel- type catalysts were compared under similar conditions.