【摘要】 采用等体积浸渍法制备了负载型铁基催化剂,并利用N₂吸附-脱附、XRD、H₂-TPR等方法对催化剂进行表征。考察了不同载体和K助剂对负载型铁基催化剂上合成气制低碳烯烃反应的影响及工艺条件对10Fe-2K/Na Y催化剂反应性能的影响。实验结果表明,相比其他三种分子筛载体,八面沸石分子筛Na Y因具有较大的比表面积且负载的铁基催化剂在反应中活性组分得到有效的还原而获得最高的反应活性;在纯铁催化剂中加入助剂K可以促进CO在活性金属铁上的解离吸附并抑制H₂的吸附,从而大幅提高CO转化率和低碳烯烃选择性;在反应温度为320℃、反应压力为2.0 MPa、反应重时空速为2 000 h^-1的条件下,10Fe-2K/Na Y催化剂CO转化率达到78.3%,低碳烯烃选择性达到61.8%,烯烷摩尔比为8.26。更多还原

【Abstract】 The supported Fe-based catalysts were prepared by an incipient wetness impregnation method and further characterized with the introduction of N₂ adsorption-desorption,XRD,and H₂-TPR techniques.The influence of different supporters and K promoter on the reaction of syngas to olefin over supported Fe-based catalysts was investigated.The reaction condition on the catalytic performance of 10Fe-2K/Na Y was also illustrated.The results show that FAU type Na Y supported Fe-based catalyst exhibits the highest reaction activity in that Na Y has a comparatively larger specific surface area compared with other three types of zeolites as supports and the active component of catalyst can be effective reduced during the reaction.The desorption of CO on the active metal Fe is promoted and the adsorption of H₂ is inhibited with the addition of K promoter to Fe-based catalyst,which leads to dramatically increasing in the conversion rate of CO and selectivity of light olefins.Under the condition of reaction temperature 320℃,pressure at 2.0 MPa and WHSV 2 000 h^-1,the conversion rate of CO,selectivity of light olefin and the ratio of olefins to paraffins is 78.3%,61.8%and 8.26,respectively,while using 10Fe-2K/Na Y as catalyst.更多还原