焦化粗苯两段加氢精制Ni-Mo/TiO_2-Al_2O_3和Co-Mo-P/TiO_2-Al_2O_3催化剂

采用分步浸渍法制备了系列Ni-Mo/TiO_2-Al_2O_3和Co-Mo-P/TiO_2-Al_2O_3催化剂,在固定床微型反应装置上考察了n(Ni):n(Ni+Mo)、n(Co):n(Co+Mo)、P的添加量对催化剂预加氢和主加氢反应性能的影响;对粗苯两段加氢精制的工艺条件进行了研究。实验结果表明,2Ni-8Mo/TiO_2-Al_2O_3预加氢催化剂(NiO和MoO_3质量分数分别为2%和8%)和2Co-8Mo-1P/TiO_2-Al_2O_3主加氢催化剂(CoO,MoO_3,P_2O_5质量分数分别为2%,8%,1%)对粗苯加氢反应效果最好;粗苯两段加氢精制最优工艺条件为:预加氢反应温度190～230℃、主加氢反应温度310～360℃、反应压力2.0～3.5MPa、液态空速2.0～3.5h~(-1)、氢油体积比350～800,在此条件下加氢液体产物中噻吩硫含量为零,苯、甲苯和二甲苯总收率保持在99%以上;催化剂在160h的稳定性实验中表现出良好的稳定性。

Ni-Mo/TiO2-Al2O3 and Co-Mo-P/TiO2-Al2O3 Catalysts for Hydrorefining of Coking Crude Benzol

Ni-Mo/TiO_2-Al_2O_3 and Co-Mo-P/TiO_2-Al_2O_3 catalysts were prepared through a multi- step impregnation method.Effects of Ni(Co)/Mo mole ratio and phosphorus content on performances of these catalysts in two-stage hydrorefining of coking crude benzol were evaluated in a fixed-bed microreactor.Reaction conditions for the two-stage hydrorefining of coking crude benzol were investigated.2Ni-8Mo/TiO_2-Al_2O_3 and 2Co-8Mo-IP/TiO_2-Al_2O_3 were found the two best catalysts for pre-hydrogenation and main hydrogenation of coking crude benzol respectively,in which mole ratio of Ni to(Ni+Mo)and Co to(Co+Mo)were 0.325 and 0.324,and mass fractions of NiO,CoO, MoO3 and P_2O_5 were 2%,2%,8% and 1%,respectively.Thiophenic sulfnr content in the liquid products was zero and total recovery of benzene,toluene and xylene reached more than 99% under the optimized reaction conditions:pre-hydrogenation temperature 190-230℃,main hydrogenation temperature 310-360℃,pressure 2.0-3.5 MPa,LHSV 2.0-3.5h~(-1)and volume ratio of H_2 to oil 350-800.All the two catalysts exhibited good stability in a 160 h life test.