Ti-MWW分子筛催化硫醚氧化反应的机理  

Mechanism of Catalyzed Oxidation of Thioether by Ti-MWW Zeolite

作　　者：卞贺 张健[1] 高志杰 张会明 徐斌 张士国 夏道宏 BIAN He;ZHANG Jian;GAO Zhijie;ZHANG Huiming;XU Bin;ZHANG Shiguo;XIA Daohong(Department of Chemical Engineering and Safety,Binzhou University,Binzhou 256603,China;China State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Qingdao 266580,China)

机构地区：[1]滨州学院化工与安全学院,山东滨州256603 [2]中国石油大学(华东)重质油国家重点实验室,山东青岛266580

出　　处：《石油学报（石油加工）》2019年第5期874-882,共9页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：山东省自然科学基金项目(ZR2015BL012,ZR2018QB007,ZR2016BL09);滨州市科技发展计划项目(2014ZC0321);滨州学院科研基金项目(BZXYG1607)资助

摘　　要：采用密度泛函理论的B3LYP-D3方法,在6-31G(d,p)基组水平上研究了钛硅分子筛(Ti-MWW)/过氧化氢(H 2O 2)体系T3位点活性中心上二甲基硫醚(DMS)氧化反应的微观机理,并考察了不同溶剂分子对Ti-MWW分子筛催化性能的影响。结果表明:不同溶剂分子在活性中心上的吸附能力由强到弱依次为CH 3COCH 3、CH 3OH、H 2O、CH 3CN;钛-氧活性中间体的催化活性由大到小依次为Ti-η^2-OOH-CH 3OH、Ti-η^2-OOH-CH 3COCH 3、Ti-η^2-OOH-H 2O、Ti-η^2-OOH-CH 3CN、Ti-η^2-OOH、Ti-η1-OOH。Ti-MWW分子筛作为催化剂显著降低了二甲基硫醚与过氧化氢氧化反应的能垒,有利于反应的发生。The oxidative reaction mechanism of dimethyl sulfide on the T3 site in titanium silicalite Ti-MWW/H 2O 2 system was studied at the B3LYP-D3/6-31G(d,p)level of theory as well as effects of solvents on the catalytic performance.The results show that the adsorption capacity of solvents on active centers follows the descend order:CH 3COCH 3,CH 3OH,H 2O,CH 3CN,and the catalytic activity follows the descend order:Ti-η^2-OOH-CH 3OH,Ti-η^2-OOH-CH 3COCH 3,Ti-η^2-OOH-H 2O,Ti-η^2-OOH-CH 3CN,Ti-η^2-OOH,Ti-η1-OOH.Moreover,it is found that Ti-MWW zeolite significantly reduces the energy barrier for the reaction between DMS and H 2O 2,which makes the reaction occur more easily.

关 键 词：密度泛函理论 钛硅分子筛(Ti-MWW) 二甲基硫醚 氧化脱硫 

分 类 号：TQ426.94[化学工程]