Perovskite-type chloro-oxide SrCoO_3-δCl_σ: A novel and durable catalyst for the selective oxidation of ethane to ethene

The catalytic performances and characterization of SrCoO_{3-0. 401} and SrCoO_{3-0. 450}Cl_{0. 126} catalysts have been investigated for the oxidative dehydrogenation of ethane (ODE) to ethene. XRD results indicated that both catalysts were of cubic perovskite-type structures. The incorporation of chloride ions in the SrCoO_3-δ lattice can significantly enhance C₂H₆ conversion and C₂H₄ selectivity. The catalyst showed 89. 6% C₂H₆ conversion, 67. 1% C₂H₄ selectivity, and 60. 1% C₂H₄ yield under the reaction conditions of C₂H₆/O₂/N₂ = 2/1/3. 7, temperature = 660°C, and space velocity = 6000 mL h^-1 g^-1. Over SrCoO_{3-0. 450}Cl_{0. 126}, with the rise in space velocity, C₂H₆ conversion decreased, whereas C₂H₆ selectivity increased. Life studies showed that SrCoO_{3-0. 450}Cl_{0. 126} was durable. The results of XPS and pulsing studies indicated that the inclusion of chloride ions in the SrCoO_3-δ lattice could promote lattice oxygen mobility. Based on the results of O₂-TPD and TPR studies, we suggest that the oxygen species desorbed at ca 695°C were active for the selective oxidation of ethane. By regulating the oxygen vacancy density and Co⁴⁺/Co ratio in the perovskite-type chloro-oxide catalyst, one can generate a durable catalyst with excellent performance for the ODE reaction.