Mo、W对Ni/γ-Al2O3催化剂烯烃加氢性能的影响

采用浸渍法制备了一系列NiM/γ-Al2O3（M＝Mo、W）催化剂。通过馏分油（沸点70℃～350℃）烯烃的加氢饱和，考察了Mo、W对Ni基催化剂加氢性能的影响，并采用TPR、XRD、XPS对催化剂进行表征。TPR结果表明，添加助剂Mo（W）降低了低温还原峰温度，但还原度有所降低，而且NiMo催化剂还原度的降低幅度比NiW催化剂更大；XRD结果表明，Mo（W）的添加提高了活性组分Ni的分散度，并且Mo的助分散作用优于W；XPS结果表明，Mo（W）的引入提高了催化剂体系“表面NiAl2O4”的比例，Ni2p3/2谱峰的化学位移说明助剂的添加增强了Ni与载体γ-Al2O3之间的相互作用。

Effect of Mo and W addition on performance of Ni/γ-Al2O3 catalyst for olefins hydrogenation

A series of alumina supported Ni, Mo-Ni and W-Ni catalysts were prepared by co-impregnation and the structure and nickel species were characterized by XRD, TPR and XPS. The effect of additive Mo(W) on catalyst activity for the hydrogenation of olefins in the fraction (boiling spread: 70℃～350℃) was studied. TPR characterization reveals the addition of additives shifts the high-temperature reduced peak to higher temperature but the low-temperature reduced peak to lower one. For the decrease of deoxidizing temperature, the effect of Mo is better than that of W. XRD measurements show that Mo and W increase the dispersion of NiO on the supports in the order of Mo>W. XPS analyse reveals the ratio of surface NiAl2O4 increases due to the presence of Mo and W. The shift of Ni2p3/2 peak indicates a stronger interaction between the NiO and γ-Al2O3 support.