载体效应对Ru催化剂F-T反应性能的影响

摘要

Series of Ru-based F-T synthesis catalysts,respectively with different supports of SiO2,Al2O3 and Beta zeolite,were prepared by impregnation method.Characterization techniques such as N2-adsorption,XRD,NH3-TPD,H2-TPR,H2-TPD,XPS and CO-DRIFTS were used to study the textural structure,phase,acidity,reduction behavior,chemical adsorption and electron properties of the catalysts.F-T synthesis performances of the catalysts were investigated as well.The results indicated that the supports imposed obvious effects on the reduction and dispersion of Ru,therefore led to the differences in acidity and surface properties of the catalysts.F-T reaction performance showed that the relatively stable Ru/SiO2 catalyst exhibited high selectivity to heavy hydrocarbons,ascribing to its less acidity,weaker metal-support interaction,and better Ru particle dispersion.%采用浸渍法将Ru负载于SiO2、Al2O3和Beta分子筛制备了不同载体的Ru基F-T合成催化剂.通过N2-物理吸附、XRD、NH3-TPD、H2-TPR、H2-TPD、XPS和CO-DRIFTS等表征方法对不同催化剂的织构、物相、酸性、还原性质、吸附性能和电子状态信息进行了考察,并对不同载体催化剂的F-T反应性能及产物分布进行了研究.结果表明,不同载体Ru基催化剂在金属分散度、还原性质、对氢气吸附性能和电子状态等方面均存在较大差异.其中,酸性较弱的Ru/SiO2催化剂具有较弱的金属载体相互作用、较小的颗粒粒径和较高的电子密度,同时该催化剂的Ru金属平台位点较多,导致其在F-T反应过程中表现较好的反应稳定性,其产物以重质烃为主,CH4和轻质烃选择性较低.