SiO_2改性AlPO_4—5/Al_2O_3复合载体催化剂的表征及加氢性能

Characterization and hydrogenation performance of SiO_2 modified AlPO_4—5/Al_2O_3 composite carrier catalyst

为了考察SiO_2对W-Ni催化剂加氢脱硫活性的影响,将SiO_2以硅溶胶形式引入AlPO_4—5/Al_2O_3复合载体,制备W-Ni催化剂,对改性的复合载体及催化剂进行BET、NH3-TPD、DRS及LRS方法表征,采用二苯并噻吩的模型化合物对催化剂脱硫活性进行微反评价。结果表明:将SiO_2引入AlPO_4—5/Al_2O_3复合载体,可改善活性金属与载体间的相互作用,提高催化剂的酸强度,促进金属组分的易还原性;SiO_2质量分数为12.0%时,催化剂的加氢活性最高,说明适当加入SiO_2有利于提高催化剂加氢脱硫活性。质量分数为12.0%的SiO_2改性复合载体制备的催化剂Cat-NiW/Si12AP对大庆催化柴油加氢评价结果表明,该催化剂具有良好的加氢脱硫、脱氮及芳烃饱和性能。

In order to investigate the effect of SiO_2 on the hydrodesulfurization activity of W-Ni catalyst,SiO_2 was introduced into AlPO_4—5/Al_2O_3 composite carrier in the form of silica sol,W-Ni catalyst was prepared and the BET,NH3-TPD,DRS and LRS were carried out on the modified composite carrier and catalyst.The model compounds of dibenzothiophene were used to evaluate the desulfurization activity of the catalysts.The results show that the introduction of SiO_2 into AlPO_4—5/Al_2O_3 composite carrier improves the interaction between the active metal and the carrier,improves the acid strength of the catalyst,the metal components can be easily reduced.When SiO_2 mass fraction is 12.0%,the hydrogenation activity of the catalyst is the highest,which indicates that the proper adding of SiO_2 is beneficial to improvement of the hydrodesulfurization activity of the catalyst.The catalyst Cat-NiW/Si12AP,which was prepared by SiO_2 modified composite support with mass fraction of 12.0%,was evaluated by Daqing catalytic diesel.The results show that the catalyst possesses good hydrodesulfurization,denitrogenation and aromatics saturation performance.