中文摘要：

研究了二氧化碳气氛下NiO/Al2O3催化剂上异丁烷脱氢制异丁烯的反应性能,考察了助剂K2O对NiO/Al2O3催化性能的影响。结果表明,与在惰性气氛下的反应相比,在二氧化碳气氛下异丁烷脱氢与逆水煤气变换反应耦合,促进了异丁烷脱氢反应,异丁烯的收率得到提高。助剂K2O的加入,能降低催化剂的酸性,减缓反应过程中催化活性物种NiO的过度还原,并抑制异丁烷裂解及积炭生成等副反应,从而提高了异丁烯的收率以及催化剂的稳定性。

英文摘要：

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.