与已经工业化的丙烷直接脱氢制丙烯技术相比,丙烷氧化脱氢制丙烯因其放热反应的特点,可以在较低的温度下完成反应从而降低了能耗,且氧气的存在抑制了催化剂的积炭等优点而备受关注.然而,在过去三十年的研究历程里,丙烯的低选择性和低收率始终是该技术工业化面临的主要问题.本文从钒基催化剂上丙烷氧化脱氢的反应机理入手,对比了有氧和无氧条件下的丙烷氧化脱氢反应,分析了氧气的存在对丙烯选择性造成的不利影响,介绍了近几年所采用的提高丙烯选择性和收率的新的工艺方法,简述了颇具工业化前景的流化床反应器和膜反应器在丙烷氧化脱氢反应中的应用.氧气的存在是造成丙烯选择性低的重要原因,实现无氧条件下的丙烷氧化脱氢反应过程和催化剂的循环再生过程同时进行有望成为新的研究趋势.%Oxidative dehydrogenation(ODH)of propane has become an attractive way to produce propene because of the low energy requirements for an exothermic and low temperature process,and little coke formation in the presence of oxygen. However,the low selectivity and yield toward propene are two main issues in propane ODH process over the past three decades which hinders its industrial application. In this paper,the possible mechanisms of ODH of propane over vanadia-based catalyst have been introduced in detail. The detrimental impact of O2 on the propene selectivity has been analyzed and the comparison of propane ODH with and without O2 has been carried out. New processes to improve propene selectivity and yield have been introduced. The applications of fluidized bed reactor and membrane reactor are discussed which might be a promising alternative for propene production in the future. The existence of O2 decreases the propene selectivity,and therefore,to realize ODH of propane in the absence of O2 and the catalyst regeneration at the same time will be a promising research direction.
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