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将Al和/或Ce的硝酸盐与NH_4HCO_3球磨混合,采用机械化学法制备了Al_2O_3-CeO_2载体(其中Ce含量为1-10 wt%),再以杂多钼酸盐(NH_4)_4NiMo_6O_(24)为活性金属Ni和Mo的前驱体,通过浸渍法制备NiMo_6/Al_2O_3-CeO_2催化剂,并将其用于1-苯并噻吩(BT)的加氢脱硫(HDS)反应中.运用化学分析、X射线衍射、N_2吸附-脱附法、H_2程序升温还原、NH_3程序升温脱附和X射线光电子能谱对催化剂的物化性质进行了表征.结果表明,催化剂的酸性随着载体中Ce含量的增加而下降.Ce修饰的Al_2O_3载体表面的NiS/MoS原子比下降了2倍.NiMo_6/Al_2O_3催化剂表现出最高的HDS活性(以单位重量催化剂计),其酸性和表面MoO_xS_y物种的浓度(Mo~(5+)浓度)也最高;当催化剂中Ce含量逐渐增加到10 wt%以上时,其活性逐渐将为0.与浸渍法制得的参比催化剂相比,前驱体和催化剂组成相同的情况下,采用机械化学法制得的所有催化剂活性明显提高.
The Al_2O_3-CeO_2O_3 support (Ce content is 1-10 wt%) was prepared by ball milling of Al and / or Ce nitrate and NH_4HCO_3, and the heteropolymolybdate (NH_4) _4NiMo_6O_ (24) NiMo_6 / Al_2O_3-CeO_2 catalysts were prepared by impregnation method and used in the HDS reaction of 1-benzothiophene (BT) as precursors of active metals Ni and Mo. The chemical analysis, X-ray X-ray photoelectron spectroscopy (XRD), X-ray photoelectron spectroscopy (XRD) and X-ray photoelectron spectroscopy (XRD) were used to characterize the catalysts. Ce on the surface of Al 2 O 3 Ce-doped NiS / MoS atomic ratio decreased by 2 times.NiMo 6 / Al 2 O 3 catalyst showed the highest HDS activity (unit weight of catalyst), the acidity and surface MoO_xS_y species concentration (Mo ~ (5+) Concentration) is also the highest; when the Ce content of the catalyst is gradually increased to above 10 wt%, its activity gradually will be 0. Compared with the reference catalyst prepared by impregnation method, the precursor and the catalyst composition of the same case, the use of mechanochemical All of the catalyst activity of the legal system was significantly raised .