菲在不同加氢催化剂上的转化

Hydrogenation of Phenanthrene Over Different Catalysts

采用孔饱和共浸渍法制备了CoMo/Al2O3、NiMo/Al2O3和NiW/Al2O3加氢催化剂。采用H2-TPR表征了其还原性能,并与Co/Al2O3、Ni/Al2O3、Mo/Al2O3和W/Al2O3进行对比。在连续流动固定床加氢微反装置上,考察了菲在不同催化剂上加氢反应的转化率和选择性。结果表明,CoMo/Al2O3、NiMo/Al2O3和NiW/Al2O33个催化剂中,NiMo/Al2O3比CoMo/Al2O3容易还原,NiW/Al2O3最难以还原。其原因主要是由于Mo与Al2O3相互作用比W弱,相对更容易还原;以及Ni比Co对促进Mo(W)还原的效果更显著。在相同的加氢反应条件下,NiMo/Al2O3和NiW/Al2O3均比CoMo/Al2O3表现出更好的菲加氢饱和性能,NiMo/Al2O3比NiW/Al2O3具有更高的低温加氢活性。在菲转化率相当时,NiMo/Al2O3和NiW/Al2O3表现出更高的八氢菲和全氢菲选择性,而CoMo/Al2O3则表现出较高的二氢菲选择性,这主要是由于Ni和Co助剂对Mo(W)作用效果不同。

Three hydrogenation catalysts（CoMo/Al2O3,NiMo/Al2O3 and NiW/Al2O3） were prepared by pore volume co-impregnation method.Their reducibility was characterized by H2-TPR and compared with Co/Al2O3,Ni/Al2O3,Mo/Al2O3 and W/Al2O3.The evaluation of the hydrogenation of phenanthrene over these catalysts was carried out in a continuous flow fixed-bed micro-reactor.The results showed that among the oxidized catalysts of CoMo/Al2O3,NiMo/Al2O3 and NiW/Al2O3,NiMo/Al2O3 is reduced more easily than CoMo/Al2O3,but NiW/Al2O3 is the most difficult reduced one,which can be ascribed to that on one hand,Mo is easier to reduce than W because the former has less strong metal-support interaction than the latter;on the other hand,Ni is better than Co in promoting the reduction of Mo（W）.Compared with CoMo/Al2O3 at the same hydrogenation conditions,NiMo/Al2O3 and NiW/Al2O3 exhibit higher activity in phenanthrene hydrogenation,and the hydrogenation activity of NiMo/Al2O3 is better than that of NiW/Al2O3 at relatively lower reaction temperatures.At equivalent phenanthrene conversion,higher selectivity of octahydrophenanthrene and perhydrophenanthrene are found over NiMo/Al2O3 and NiW/Al2O3,but CoMo/Al2O3 shows better selectivity in dihydrophenanthrene,due to the difference of the promoting effect of Ni and Co on Mo（W）.