作　　者： ; ;

机构地区： 复旦大学化学系

出　　处： 《Chinese Journal of Catalysis》 1995年第3期190-195,共6页

摘　　要： 应用ＸＲＤ，ＸＰＳ，ＩＲ－ＴＰＤ，ＣＯ２和ＮＯ吸附及正庚烷裂解和噻吩加氢脱硫脉冲激反等方法，研究了加氢处理催化剂载体经Ｙ型分子筛改性前后各种性质的变化．结果表明，载体经Ｙ型分子筛改性后，催化剂的Ｂ酸、正庆烷裂解活性和异构选择性明显提高．Ｙ型分子筛以分散的形式分布于ｙ－Ａｌ２Ｏ３表面，减少了载体表面的空位铝．该催化剂中有相当一部分金属组分进入Ｙ型分子筛孔道与其Ｂ酸位作用．与ＮｉＷ／γ－Ａｌ２Ｏ３相比，这种催化剂的表面金属组分浓度减小，但八面体构型的组分却增加，这有利于提高催化剂的加氢脱硫能力． RD, XPS, acidity measurement with IR-TPD, NO and CO2chemisorption were used to study the surface structure and acidic property of NiW/γ-Al2O3, NiW/γ-Al2O3+USY and the supports of γ-Al2O3and γ-Al2O3+USY. The hydrodesulfurization (HDS) of thiophene andhydrocracking of heptane in oxidic state also have been studied. The results clearly showed that when the support γ-Al2O3 was modified byadding Y zeolite, the number of Bronsted acid sites of the catalyst wasincreased, the cracking activity, as well as the selectivity for isomerization was raised. In γ-Al2O3+USY, the USY zeolite scattered over thesurface of γ-Al2O3 and made the free aluminium of γ-Al2O3 decrease.Loaded on the modified support, Ni, W can not only be dispersed overthe surface of γ-Al2O3 but also over the surface of zeolite, and interactedwith the Bronsted acid sites. However, in the modified support, thesurface density of Ni, W decreased and Ni, W preferred to form moreoctahedral coordination. Because NiW/γ-Al2O3+USY catalyst hadmore octahedral coordination of nickel and tungsten than that of NiW/γ-Al2O3, its HDS activity of thiophene was improved.

关 键 词： 催化剂 分子筛 表面性质 加氢裂化

领　　域： [化学工程] [理学] [理学]