【摘要】 采用浸渍-化学还原法制备了Ru/ZrO₂催化剂,并采用Pd或Pt对其进行了修饰.采用N₂物理吸附、H₂化学吸附、粉末X射线衍射（XRD）、紫外-可见漫反射光谱（UV-DRS）、透射电子显微镜（TEM）、X射线吸收光谱（XAS）和差示扫描量热（DSC）等手段对催化剂进行了系统的表征.研究表明,Pd、Pt均与Ru在催化剂表面形成了合金,从而提高了Ru的配位数.在苯部分加氢反应中,Pd、Pt的引入使催化剂上苯的转换频率（TOF）有所降低,但能提高环己烯的初始选择性（S₀）.在最优的Ru-Pd/ZrO₂-0.2和Ru-Pt/ZrO₂-0.15催化剂（Pd、Pt与Ru的摩尔比分别为0.2和0.15）上,S₀及环己烯得率接近,分别可达近77%和44%.结合催化剂的表征和加氢结果,探讨了Pd、Pt影响Ru/ZrO₂催化剂苯部分加氢活性和选择性的原因.更多还原

【Abstract】 We report the modification effects of Pd and Pt on the partial hydrogenation of benzene to cyclohexene over the Ru/ZrO₂ catalyst. The Ru/ZrO₂, Ru-Pd/ZrO₂ and Ru-Pt/ZrO₂ catalysts were prepared by the wetness impregnationchemical reduction method at room temperature. The catalysts were characterized by N₂ physisorption, H₂ chemisorption, powder X-ray diffraction（XRD）, ultraviolet-visible diffuse reflectance spectroscopy（UV-DRS）,transmission electron microscopy（TEM）, X-ray absorption spectroscopy（XAS）, and differential scanning calorimetry（DSC）. It was identified that the Ru-Pd and Ru-Pt alloys were formed on the Ru-Pd/ZrO₂ and Ru-Pt/ZrO₂ catalysts,which improved the coordination number of Ru. In the partial hydrogenation of benzene to cyclohexene, while the modification of the Ru/ZrO₂ catalyst with Pd or Pt decreased the turnover frequency（TOF） of benzene, the initial selectivity（S₀） to cyclohexene was improved. The Ru-Pd/ZrO₂-0.2 and Ru-Pt/ZrO₂-0.15 catalysts with the optimal Pd/Ru and Pt/Ru molar ratios of 0.2 and 0.15 exhibited similar S₀ and the yield of cyclohexene of about 77% and 44%,respectively. On the basis of the characterization results, the modification effects of Pd and Pt on the activity and selectivity of the Ru/ZrO₂ catalyst were discussed.更多还原