硫化温度对MoCo/Al_2O_3催化剂选择性加氢脱硫的影响

EFFECT OF PRESULFURIZATION TEMPERATURE ON THE SELECTIVE HYDRODESULFURIZATION OF MoCo/Al_2O_3 CATALYST

以FCC汽油为原料，在中型试验装置上考察230～400℃范围内硫化温度对MoCo／Al2O3催化剂加氢脱硫率及烯烃加氢饱和率、产品辛烷值损失的影响。结果表明：在反应温度260℃下，随着硫化温度的提高，加氢脱硫率由84．4％逐步提高到91.1％；在反应温度280℃下，加氢脱硫率均可维持在96．0％以上，受硫化温度的影响较小。在上述两种情况下，250℃硫化时催化剂的烯烃加氢饱和率最低，辛烷值损失最小。表明250℃硫化时催化剂的加氢脱硫选择性最好。MoCo／Al2O3催化剂在250℃下硫化充分且碳含量较少是其FCC汽油加氢脱硫选择性最好的原因。

The effect of presulfurization temperature （230--400℃） of MoCo/Al2O3 catalyst on its selective hydrodesulfurization （HDS） performance, such as HDS rate, hydro-saturation （HYD） rate and gasoline octane （RON） loss,was studied on a pilot plant unit using full range FCC gasoline as feed. The test results indicated that under reaction temperature of 260℃, with the increase of presulfurization temperature,the HDS rates of these catalysts increased from 84.4% to 91. 1%; under reaction tempera- ture of 280℃ ,the HDS rates of these catalysts were all over 96.0%,presulfurization temperature had less influence. However,in these two eases,MoCo/Al2O3 catalyst sulfurized at 250℃ exhibited the minimum HYD rate and gasoline RON loss, which indicated said catalyst possessed the best HDS selectivity. It was found that MoCo/Al2O3 eatalyst could be well sulfurized at 250℃ and with less coke deposit, which would be favorable to provide good HDS selectivity when treating FCC gasoline.