Ni/sepiolite催化剂的改性研究Ⅱ.载体的改性

Studies on the modification for Ni/sepiolite catalyst II. Modified on support

以羟基铝改性sepiolite为载体制备了一系列Ni基催化剂。采用苯加氢为探针反应及二硫化碳中毒法系统地考察了载体改性对Ni/sepiolite催化剂活性及抗毒性能的影响。结果表明 ,载体的改性增加了催化剂的活性中心数 ,提高了Ni原子分散度 ,降低了加氢反应的活化能。动力学研究亦表明 ,羟基铝的引入既有电子效应又有几何效应 。

A series of nickel catalysts were prepared by impregnation with sepiolite modified by hydroxyl aluminum as the support. The influences of Al on Ni/sepiolite catalyst were investigated by benzene hydrogenation and CS 2 poisoning, respectively. The result indicates that the modification of support can increase the number of active centers and dispersion of Ni atoms over support, and decrease the activation energy of hydrogenation reaction. Besides, the studies of kinetics also reveal that the effects of Al on Ni/sepiolite include not only the steric effect but also electronic effect, furthermore the electronic effect seems to be principal.