Effect of tetrachloromethane on redox behaviors of copper(II) oxide in the oxidative dehydrogenation of propane

Abstract

The oxidative dehydrogenation of propane on CuO has been investigated at 723 K in the presence and absence of tetrachloromethane (TCM). Under oxygen-limiting conditions, the conversion of propane and the selectivity to propylene were enhanced by the introduction of TCM. The catalyst converted to metallic Cu during the oxidation in the absence of TCM while no conversion of CuO was observed in the sample used in the presence of TCM. In contrast, the conversion of propane dramatically decreased upon addition of TCM into the feedstream for the oxidation of propane under the oxygen-excess conditions. The catalyst used under the oxygen-excess conditions was not reduced to metallic Cu, regardless of the addition of TCM. It is suggested that an abstraction of lattice oxygen from the catalyst is strongly influenced by the concentration of oxygen in the feed, resulting in the different effect of TCM on the oxidative dehydrogenation of propane.