高分散镍硅催化剂对喹啉催化加氢的性能

The catalytic performance of highly dispersed nickel-silica catalyst in quinoline hydrogenation

摘要:

以硝酸镍和硅溶胶为原料，采用蒸氨水热法，制得了一系列负载量为10%（以镍在催化剂中的质量分数计，下同）的镍硅酸盐衍生的Ni-PS-AEH-x（x代表不同焙烧温度，下同）催化剂，并用于喹啉选择性加氢制取1,2,3,4-四氢喹啉。通过考察不同镍基催化剂的加氢性能，发现Ni-PS-AEH-400催化性能最好。通过考察反应条件的影响，确定最佳反应条件为：底物与金属镍投料比（物质的量之比，下同）为30：1、反应温度100 ℃、氢气压力3 MPa、反应时间120 min，此时喹啉转化率为99.0%，1,2,3,4-四氢喹啉收率为95.4%。采用XRD、TEM、N2吸附-脱附、H2-TPR和XPS表征对催化剂结构、组成、形貌进行了表征，结果表明：镍硅酸盐结构使Ni-PS-AEH-400比表面积大、镍纳米粒子分散均匀，活性中心与载体间的相互作用力强，使其在喹啉加氢反应中具有较浸渍法制备的Ni/SiO2-IMP更优异的催化性能。

Abstract:

A series of nickelphyllosilicate derived Ni-PS-AEH-x (different calcination temperatures, the same below) catalysts with a loading of 10% (mass fraction of ruthenium in a catalyst, the same below) nickel were prepared by ammonia evaporation hydrothermal method using nickel nitrate and silica sol as raw material. Ni-PS-AEH-400 was found to have the best catalytic performance by investigating the hydrogenation performance of different nickel-based catalysts. By investigating the influence of reaction conditions, the optimal reaction conditions were as follows: molar ratio of quinoline : Ni is 30 : 1, reaction temperature was 100 ℃, hydrogen pressure was 3 MPa, reaction time was 120 min, and the quinoline conversion rate was 99.0%, the yield of 1,2,3,4-tetrahydroquinoline was 95.4%.The structure, composition and morphol-ogy of catalysts were characterized by XRD, TEM, N2 adsorption-desorption, H2-TPR, and XPS. The re-sults indicated that Ni-PS-AEH-400 exhibited better catalytic performance, attributed to larger specific surface area, active particle higher dispersion and stronger interaction between the active particles and the support compared with Ni/SiO2-IMP prepared by impregnation method.