成型Ti-MWW分子筛催化环己酮液-液-固三相氨肟化反应及失活原因  

Catalytic Performance and Deactivation of the Shaped Ti-MWW Zeolite for Ammoximation of Cyclohexanone in Liquid-Liquid-Solid Three Phase System

作　　者：王妙 宋仕芋 袁霞[1] 吴剑[1] WANG Miao;SONG Shiyu;YUAN Xia;WU Jian(School of Chemical Enginering, Xiangtan University, Xiangtan 411105, China)

机构地区：[1]湘潭大学化工学院,湖南湘潭411105

出　　处：《石油学报（石油加工）》2017年第6期1183-1191,共9页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(21376201);湖南省高校2011协同创新中心资助项目资助

摘　　要：采用连续淤浆床反应装置,对比研究了环己烷为溶剂的液-液-固三相体系中成型Ti-MWW分子筛与TS-1分子筛催化环己酮氨肟化反应的性能。结果表明,成型Ti-MWW分子筛催化环己酮氨肟化的性能明显优于TS-1分子筛。催化剂寿命评价以及反应副产物的定性分析结果表明,在催速失活工艺条件下,成型Ti-MWW分子筛在环己烷为溶剂的液-液-固三相体系中稳定运行28.1h,环己酮肟选择性大于99%,反应副产物主要为高沸点极性有机物。通过对新鲜、失活及再生催化剂进行SEM、XRD、N_2物理吸附、UV-Vis和FT-IR等表征,表明成型Ti-MWW分子筛单程失活未见明显骨架硅流失,拓扑结构没有被破坏,失活主要是由反应副产物堵孔造成的。A continuous slurry reactor was used to study the catalytic performance of shapedTi-MWWand TS1zeolites in the liquidliquidsolid threephase ammoximation,with cyclohexane as the solvent.The results show that the shaped Ti-MWW had better performance than TS1for ammoximation of cyclohexanone.Deactivation behavior of the catalyst was studied and qualitative analysis of the reaction byproducts was carried out.Under the accelerated deactivation condition,the life time of shaped Ti-MWW zeolite reached281hin liquidliquidsolid threephase ammoximation and the selectivity of cyclohexanone oxime was above99%.Byproducts of the reaction were mainly high boiling point polar organic compounds.The fresh,deactivated and regenerated catalysts were characterized by various approaches,including SEM,XRD,N2physisorption,UVVis and FT-IR.The results showed that the dissolution erosion of silicon from the zeolite was negligible and the MWW framework structure did not change obviously.The byproducts blocking of the molecular sieve channels is the primary factor leading to the deactivation of shaped TiMWW zeolite in a single cycle.

关 键 词：成型T-MWW分子筛 氨肟化 环己酮肟 液-液-固三相反应 失活 

分 类 号：O643.36[理学—物理化学]