CoMoP-EG/ Al2O3催化剂的表征及其柴油加氢精制催化性能

在CoMoP共浸渍液中加入乙二醇(EG)制备CoMoP-EG/γ-Al2O3系列催化剂。采用UV-Vis、TG/DTG、FT-IR、低温N2吸附、H2-TPR、HRTEM等手段对其进行表征，并以直馏柴油为原料，采用高压微反装置评价催化剂的加氢脱硫和加氢脱氮活性。结果表明，浸渍液中的乙二醇未与活性金属离子形成新的配合物。乙二醇与载体发生相互作用形成Al-O-C键，减弱了活性组分与载体的相互作用，提高了活性组分的分散性。与未加乙二醇制备的硫化态CoMoP/γ-Al2O3相比，硫化态CoMoP-EG/γ-Al2O3催化剂中MoS2晶粒的堆垛层数增加，片层长度减少，有利于Ⅱ型Co-Mo-S活性相的形成。在反应温度350℃、氢分压6.0 MPa、空速1.5h-1、氢/油体积比400条件下，采用最佳乙二醇加入量制备的CoMoP-EG/γ-Al2O3催化剂，可使直馏柴油的硫质量分数由13298μg/g降至6μg/g，氮质量分数由169.7μg/g降至0.4μg/g。

Characterization of CoMoP-EG/Al2 O3 Catalyst and Its Catalytic Performance for Diesel Hydrogenation

CoMoP-EG/γ-Al2O3 catalysts were prepared by adding ethylene glycol (EG) to the CoMoP co-impregnation solutions and characterized by means of UV-Vis, TG/DTG, FT-IR, BET, H2-TPR, HRTEM. The HDS and HDN performances of prepared CoMoP-EG/γ-Al2O3 were evaluated in a high pressure microreactor with straight-run diesel as feed. The results indicated that there was no any new Co or Mo complex formed in co-impregnation solution when ethylene glycol was added. Ethylene glycol could interact with γ-Al2O3 to form Al-O-C bond, weakening the interaction between metals and supports and promoting the dispersion of metals on the surface of supports. Compared to sulfide CoMoP/γ-Al2O3, the stacking number of MoS2 particles in sulfide CoMoP-EG/γ-Al2O3 increased and the MoS2 slab length decreased, facilitating the formation of Co-Mo-S active phases of type Ⅱ. At the reaction conditions of θ=350℃, p(H2)=6.0MPa, V(H2)/V(Oil)=400, LHSV=1.5h-1 and with the CoMoP-EG/γ-Al2O3 of optimum ethylene glycol amount as catalyst, the sulfur and nitrogen mass fractions of straight-run diesel feedstock could be reduced from 13298 to 6μg/g and from 169.7 to 0.4μg/g, respectively.