Coupling dehydrogenation of isobutane to isobutene in the presence of carbon dioxide over NiO/Al2O3 catalyst

Dehydrogenation of isobutane to isobutene in the presence of carbon dioxide was carried out over NiO/Al2O3 catalyst and the effect of K2O additive on its catalytic behavior was investigated. Compared with the reaction in an inert atmosphere, the dehydrogenation of isobutane is coupled with the reverse water-gas shift by conducting the reaction in carbon dioxide, which can then enhance the isobutene yield. The addition of K2O in the NiO/Al2O3 catalyst can decrease its acidity, alleviate the deep reduction of NiO active species during the reaction and then suppress the side reactions like cracking and coke formation; these are helpful to enhance the isobutene yield and to improve the catalyst stability.