载体表面钛改性对负载活性组分还原性能的影响

INFLUENCE OF TITANIUM MODIFICATION ON REDUCTION TEMPERATURE OF SUPPORTED ACTIVE COMPONENTS

通过等体积浸渍法用不同含量的钛对Al2O3和SiO2载体进行改性,在改性Al2O3载体上分别负载Mo,Ni,NiP,在改性SiO2载体上负载NiP,制备了一系列加氢脱硫催化剂,研究了载体进行钛改性后,不同载体上不同活性组分的还原温度变化规律。用程序升温还原法对催化剂的还原性能进行表征。结果表明:钛改性氧化铝载体和钛改性二氧化硅载体均可以降低活性组分的还原温度;与氧化铝载体相比,NiP在氧化硅载体上的还原温度明显提高;与未改性的催化剂相比,钛改性改变了活性组分与载体之间的相互作用,降低了活性组分的还原温度。

A series of HDS catalysts were prepared using titanium modified cylindrical Al2O3 and SiO2 supports. The active components of Mo, Ni and NiP were loaded on Al2O3 and Ti modified Al2O3 supports. NiP was supported onto the SiO2 and Ti modified SiOz supports. The influence of titanium modification was investigated on the reduction temperature of the supported active components by temperature programmed reduction （TPR） method. The results show that the titanium modification can lower the reduction temperature of the active components on all catalyst tested. The reduction temperature of NiP on the silica carrier increases significantly compared with that on the alumina carrier. The reason for the lower reduction temperature of active components on the modified catalyst is due to the changes of interaction between active component and carrier by modification of titanium.