Nickel-based catalysts supported onγ-A12O3 or SiO2 from Ni(NO3)2,NiCl2 or NiSO4 as precursors were prepared with incipient technique and further reduced by H2at high temperature. Influence of nickel precursors,catalyst supports,nickel loadings and reaction conditions on the catalytic performance of phenol hydrogenation was investigated. Among three nickel precursors studied,Ni(NO3)2was the most easily reduced by H2 and the catalyst prepared displayed the best catalytic performance. It was shown that the nickel catalyst on SiO2exhibited higher performance than that onγ-Al2O3. The reasonable nickel loading was helpful to active component dispersion and good catalytic performance. The main product on the nickel supported catalysts was not the cyclohexanone but the cyclohexanol,and yet,the selectivity of cyclohexanone could be increased under the modest reaction conditions. The reaction rate or the cyclohexanone selectivity could be improved in nonpolar solvents like heptane or cyclohexane compared to that in polar solvents,like alcohol or H2O.%通过等体积浸渍法分别将Ni(NO3)2、NiCl2、NiSO43种镍前体浸渍于A12O3或SiO2载体上，然后通过H2高温还原法制备了负载型镍基催化剂，考察了镍前体、载体种类、镍负载量、反应条件等对镍基催化剂苯酚加氢性能的影响。结果表明，对比3种镍前体，在H2高温还原体系中Ni(NO3)2最容易被还原，制备的镍基催化剂苯酚加氢活性最高。SiO2负载的镍基催化剂活性远高于γ-Al2O3催化剂。适宜的 Ni 负载量有助于活性组分的分散和催化活性的提高。镍基催化剂的苯酚加氢产物以环己醇为主，相对缓和的反应条件更容易生成环己酮。在非极性溶剂正庚烷或环己烷存在下，苯酚加氢反应速率远远高于极性溶剂水或乙醇存在下的结果，而且环己酮的选择性更高。
展开▼
