摘要
采用干混法、湿混法和浸渍法制备了CoMo/Al2O3加氢脱硫催化剂.物理性质分析、X射线光电子能谱、X射线能量色散谱和程序升温硫化表征结果表明,干混法和湿混法催化剂的孔容和比表面积相当,均大于浸渍法催化剂.浸渍法催化剂的表面粒子明显大于两种混捏法.两种混捏法催化剂可以在低温区硫化,浸渍法催化剂的硫化可分别在低温区和高温区进行.干混法催化剂中Co和Mo在微区内分布不均匀,浸渍法催化剂中Co和Mo在催化剂表面的分散量明显高于催化剂内部,湿混法催化剂中Co和Mo在微区内呈均匀分布.湿混法催化剂的Co和Mo在催化剂表面的分散状态好于干混法和浸渍法,制备方法对催化剂中Co和Mo的存在环境及价态没有影响.石脑油加氢脱硫反应评价结果表明,湿混法催化剂的加氢脱硫活性高于浸渍法和干混法催化剂.
The CoMo/Al2O3 catalysts were prepared by impregnation （IM）, dry mixing （DM） and wet mixing （WM） methods, and characterized by X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy and temperature-programmed sulfiding. The specific surface area and pore volume of CoMo/Al2O3 （DM） and CoMo/Al2O3（WM） are equivalent and obviously larger than those of CoMo/Al2O3 （IM）, but the crushing strength is in the order CoMo/Al2O3 （IM） 〉 CoMo/Al2O3 （WM） 〉 CoMo/Al2O3 （DM）. The main binding energy of Co 2p and Mo 3d of the three catalysts is equal, and the preparation methods have no effect on the valence of Co and Mo in the catalysts. The apparent particle size of CoMo/Al2O3 （IM） is obviously larger than that of the other two catalysts. The sulfiding of CoMo/Al2O3（IM） takes place both at low temperatures （55-250℃ ） and high temperatures （250-560℃ ）, and there are MoS2, Co9S8 and Co4S3 crystallines on the catalyst surface after sulfiding. The other two catalysts can be sulfided at low temperatures （54-285℃ ）, and the sulfides of Co and Mo exist in amorphous phase. The distribution of Co and Mo is uniform in CoMo/Al2O3 （WM） from the surface to the interior, and it is not so uniform in CoMo/Al2O3（DM）. The Co and Mo concentration at the surface of CoMo/Al2O3（IM） is higher than that in its interior. The ammonia dissolving test results show that the dissolving ratio of MoO3 of CoMo/Al2O3 （DM） is basically equivalent to that of COMo/Al2O3 （WM）, but smaller than that of CoMo/Al2O3（IM）. The results of naphtha hydrodesulfurization show that CoMo/Al2O3（WM） has higher activity than the other two catalysts.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2005年第8期639-644,共6页
关键词
钴
钼
氧化铝
负载型催化剂
湿混法
石脑油
加氢脱硫
cobalt, molybdenum, alumina, supported catalyst, wet mixing, naphtha, hydrodesulfurization
