【摘要】 以β分子筛为载体,采用浸渍法制备不同V负载量的V/β系列催化剂,利用XRD,UV-Vis,BET,H₂-TPR,NH₃-TPD等手段对催化剂进行表征,考察了V/β催化剂丙烷氧化脱氢制丙烯的性能。表征结果显示,V/β催化剂的孔道均匀,孔分布窄,有利于丙烷进入催化剂孔道与活性组分发生作用;负载较低V时催化剂中V物种主要以高度分散的孤立四配位V⁵⁺形态存在,随负载V含量的增加,二维链状聚集态V物种增加,负载V过多时易形成晶相V₂O₅;负载的V覆盖了部分B分子筛自身的酸性位,并在β分子筛表面产生弱酸性位,使丙烯的脱附变易,提高了丙烷转化率和丙烯选择性。实验结果表明,负载量8%（w）的V/β催化剂在V（C₃H₈）:V（O₂）:V（N₂）=2:1:4、气态空速8 400 h^-1、500℃时,丙烯选择性达63.2%。更多还原

【Abstract】 A series of β zeolite supported vanadium catalysts（V/β） with different V content were prepared through impregnation,and characterized by means of BET,XRD,UV-Vis,H₂-TPR and NH₃-TPD.Their performances in the oxydehydrogenation of propane to propene were studied.The results indicated that the V/β catalysts with narrow pore size distribution and uniform pore size were beneficial to propane entering the channels in the catalysts and acting with active sites.The V species with low loading mainly existed in the form of four coordinated V⁵⁺ with high dispersity.With the V loading increasing,2 dimension linear aggregative V species formed,and when the V species overloading the V₂O₅ crystal phase would appear.Part of the acid sites on the β zeolite was covered by supported V and new weak acid sites formed on the catalyst surface,which improved the propane conversion and propene selectivity.Under the conditions of F（C₃H₈）:V（O₂）:V（N₂） 2:1:4,500℃,GHSV 8 400 h^-1 and V content in the catalyst 8%（w）,the selectivity to propene reached 63.2%.更多还原