新型混捏法Co-Mo/γ-Al_2O_3加氢脱硫催化剂  

Co-Mo/γ-Al_2O_3 HDS CATALYSTS REPARED BY WET-MIXING-KNEADING METHOD

作　　者：张孔远[1] 刘爱华[1] 燕京[1] 张宏宇 刘晨光[2] 

机构地区：[1]中国石油化工股份有限公司齐鲁分公司研究院,山东淄博255400 [2]石油大学,山东东营257061

出　　处：《石油学报（石油加工）》2005年第1期6-11,共6页Acta Petrolei Sinica(Petroleum Processing Section)

摘　　要：以有机酸作为 Co、Mo 的络合剂和催化剂成型胶溶剂, 采用湿混捏法制备出了系列 Co Mo/γ Al2O3 加氢脱硫催化剂。分光光度法分析和 XPS 表征结果表明, 在 MoO3 质量分数低于 12%, CoO 质量分数低于3.4%时, Co、Mo 优先在该类催化剂的表层分散, 其表层的 Co、Mo 相对含量高于化学组成相对含量, 当Co、Mo 含量增加到在催化剂表层分散完全后, 其表层 Co、Mo 相对含量低于化学组成相对含量, 即进入体相中的 Co、Mo 的量高于表层。采用湿混捏法制备的 Co Mo/γ Al2O3 催化剂中, MoO3 在γ Al2O3 上的单分子层阈值为 7.1μmol/m2,与干混法相当,但远大于浸渍法催化剂;CoO在γ Al2O3 上的单分子层分散阈值为2.5μmol/m2, 且 CoO 的存在并未影响 MoO3 的单层分散阈值。石脑油加氢脱硫活性评价结果表明, 湿混捏法制备的 Co Mo/γ Al2O3 催化剂, 当表层的 Co、Mo 相对含量高于化学组成相对含量时, 随着活性组分含量的增加, 催化剂的脱硫活性增加, 当化学组成相对含量高于表层 Co、Mo 相对含量后, 催化剂的加氢脱硫活性增加幅度减小, 当超过其单层分散阈值以后, 随着活性组分含量的增加, 其加氢脱硫活性反而降低。A kind of Co and Mo complex compound solution was prepared with Co and Mo salt and an organic acid. A series of Co-Mo/γ-Al2O3 hydrodesulfurization catalysts were prepared with this kind of complex compound solution and pseudobohmite by wet-mixing-kneading method. Results of spectrophotometry and XPS analysis showed that when the mass fraction of MoO3 was lower than 12% and the mass fraction of CoO lower than 3.4%, Co and Mo took precedence to disperse on the surface of this kind of catalyst, and n(Mo3d)/n(Al2p) (surface composition) was bigger than n(Mo)/n(Al) (chemical composition), n(Co2p)/n(Al2p) (surface composition) was bigger than n(Co)/n(Al) (chemical composition); when the mass fractions of Co and Mo increased to a degree that Co and Mo completely dispersed on catalyst surface, the mass fractions of Co and Mo in catalyst bulk were greater than that of dispersed on catalyst surface. The MoO3 monolayer dispersion threshold of wet-mixing-kneading catalyst was determined to be 7.1 μmol/m2, which was much bigger than that of the impregnation catalyst and equivalent to that of dry-mixing kneading catalyst. The CoO monolayer dispersion threshold of wet-mixing-kneading catalyst was determined to be 2.5 μmol/m2. The presence of CoO in Co-Mo/γ-Al2O3 catalyst presented no effect on MoO3 monolayer dispersion threshold. The naphtha HDS activity evaluation showed that HDS activity increased with the increase of MoO3 and CoO mass fractions when n(Mo3d)/n(Al2p) was bigger than n(Mo)/n(Al), n(Co2p)/n(Al2p) was bigger than w(Co)/n(Al); the increase rate slowed down when n(Mo)/n(Al) was bigger than n(Mo3d)/n(Al2p), n(Co)/n(Al) was bigger than n(Co2p)/n(Al2p)yet lower than the threshold; and that the HDS activity decreased on the contrary, with the increase of MoO3 and CoO mass fractions when it was higher than the threshold.

关 键 词：催化剂 制备方法 单层分散 加氢脱硫 

分 类 号：TE624.93[石油与天然气工程—油气加工工程]