Ni对MoS_(2)基催化剂活性相及加氢脱氮脱硫性能的影响  

Influence of Ni on the active phase and hydrodenitrogenation and hydrodesulfurization activities of MoS_(2)catalysts

作　　者：刘娟[1,2] 李文英[1] 冯杰[1] 高翔[2] LIU Juan;LI Wen-ying;FENG Jie;GAO Xiang(State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan 030024,China;State Key Laboratory of Clean Energy Utilization,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]太原理工大学省部共建煤基清洁能源利用国家重点实验室,山西太原030024 [2]浙江大学能源清洁利用国家重点实验室,浙江杭州310027

出　　处：《燃料化学学报》2021年第10期1513-1521,共9页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(22038008);国家重点研发计划重点专项(2016YFB0600305)资助。

摘　　要：为了获得较多高活性II型MoS_(2)活性相,采用四硫代钼酸铵原位热分解法制备了MoS_(2)基催化剂,对比分析了Ni源引入方式和热分解气氛对MoS_(2)活性相微观结构、表面元素化学状态和加氢脱氮脱硫性能等的影响。结果表明,同时引入Mo源和Ni源原位沉淀生成无定形NiMoS4后,再热分解有利于Ni取代MoS_(2)片晶边缘的Mo原子,被修饰后的MoS_(2)片晶保持较高的分散度、适宜的长度(3−5 nm)和堆叠层数(2−4层),从而在边缘暴露较多具有加氢和氢解活性的rim和corner活性位点。热分解气氛H_(2)比N_(2)更有利于Ni在热分解过程中取代MoS_(2)边缘的Mo原子,形成更多II型Ni-Mo-S活性结构,有利于喹啉和二苯并噻吩的吸附活化和加氢反应。当加氢反应温度340℃、氢压3 MPa、重时空速23.4 h−1、氢油比为600和使用0.1 g NMS-H_(2)催化剂时,喹啉加氢脱氮转化率达23.8%,二苯并噻吩加氢脱硫转化率达93.3%。To obtain type II active phase with higher activity,MoS_(2)-based catalysts were prepared by thermal decomposition of ammonium tetrathiomolybdate.The influence of Ni adding way and decomposition atmosphere on the microstructures of MoS_(2)slabs,chemical state of surface elements,as well as hydrodesulfurization and hydrodenitrogenation activities were investigated.Results indicated that simultaneous impregnation of Mo and Ni precursors caused in situ deposition of amorphous NiMoS4 over the support surface,which subsequently facilitated the substitution of Mo atoms by Ni atoms at MoS_(2)edges.Accordingly,these decorated catalysts exhibited higher dispersion of MoS_(2)slabs with more suitable slab length(3–5 nm)and stacking number(2–4),which attributed to larger numbers of rim and corner active sites exposed at the edges.These active sites were essential in hydrogenation and hydrogenolysis reactions.In comparison with N_(2)atmosphere,thermal decomposition in H_(2)atmosphere was more conducive to the substitution of Mo atoms by Ni atoms at MoS_(2)edges,which provided more active Ni-Mo-S structures for the adsorption,activation and hydrogenolysis of quinoline and dibenzothiophene molecules.The catalyst prepared by thermal decomposition of NiMoS4 in H_(2)atmosphere showed superior activities in the quinoline hydrodenitrogenation with 23.8%conversion and in the dibenzothiophene hydrodesulfurization with 93.3%conversion,under the conditions of 340℃,3 MPa,a weight hourly space velocity of 23.4 h–1,H_(2)/oil volume ratio of 600 and 0.1 g of NMS-H_(2)catalysts.

关 键 词：NiMo硫化物 喹啉 二苯并噻吩 加氢反应 

分 类 号：TQ426[化学工程]