核-壳结构多酸/磁性铈铁纳米复合氧化物@SiO 2吸附-氧化脱硫性能  

Adsorption-Oxidative Desulfurization Performance of Core-Shell Polyoxometalate/Magnetic Cerium-Iron Nanocomposite Oxide@SiO2

作　　者：赵柳 宋胜杰 马康富 王宏 付丽华 刘新阳 陈立东[1] 成卫国[2] ZHAO Liu;SONG Shengjie;MA Kangfu;WANG Hong;FU Lihua;LIU Xinyang;CHEN Lidong;CHENG Weiguo(Faculty of Chemistry and Chemical Engineering,Liaoning Normal University,Dalian,Liaoning 110629,China;Beijing Key Laboratory of Ionic Liquids Clean Process,Key Laboratory of Green Process and Engineering,Chinese Academy of Sciences,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 110190,China)

机构地区：[1]辽宁师范大学化学化工学院,辽宁大连116029 [2]中国科学院过程工程研究所,多相复杂系统国家重点实验室,离子液体清洁过程北京市重点实验室,绿色过程与工程重点实验室,北京110090

出　　处：《应用化学》2020年第12期1457-1464,共8页Chinese Journal of Applied Chemistry

基　　金：辽宁省教育厅服务地方项目(LF2019002);辽宁省普通高等教育本科教学改革研究项目(辽教函[2018]471号);辽宁师范大学教师教育中心专项课题(lsjsjyzx201905);中国科学院战略性先导科技专项(XDA21030500)资助。

摘　　要：水热法合成了铈铁纳米复合氧化物,采用化学沉积法在其表面包裹SiO 2制备核-壳结构磁性材料,以其为载体负载H 2 O 2结合Keggin结构磷钼酸(HPMo)制备了HPMo-H 2 O 2/CeFe x O y@SiO 2吸附-氧化脱硫催化剂。采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶红外光谱(FT-IR)、X射线粉末衍射(XRD)、氮气吸附脱附(BET)、31 P魔角核磁共振(MAS-NMR)和X射线光电子能谱(XPS)等对催化剂的结构进行表征。结果表明,SiO 2将CeFe x O y包裹形成核-壳结构纳米复合材料,以其为载体负载HPMo-H 2 O 2后Keggin型多酸的骨架结构保持,并产生少量过氧化磷钼酸盐活性物种。不同催化剂对有机硫化物二苯并噻吩(DBT)的吸附脱硫和氧化脱硫性能,均呈现出HPMo-H 2 O 2/CeFe x O y@SiO 2>CeFe x O y@SiO 2>CeFe x O y的活性顺序,多酸的引入大大提升了其对大分子有机硫化物的吸附和氧化脱除性能,催化氧化脱硫活性的提高源于多酸分子“假液相”反应过程的结果。在反应温度60℃,反应3 h,m(油)∶m(催化剂)=35∶1,n(O)∶n(S)=10∶1的条件下,对DBT氧化脱除率达到99.4%。制备的磁性核-壳结构氧化脱硫剂有理想的氧化脱除DBT的循环使用性能,并且可通过外加磁场进行简单分离,是一类制备方法简单、催化活性高且稳定性好的绿色环保型催化剂。The manganese-cerium mixed iron oxide nanocomposites were synthesized by hydrothermal synthesis method.The surface was wrapped by SiO 2 by chemical vapor deposition to prepare the core-shell magnetic material which was then loaded by H 2 O 2 with Keggin structure phosphomolybdic acid(HPMo)to synthesize the HPMo-H 2 O 2/CeFe x O y@SiO 2 adsorption-oxidative desulfurization catalyst.The catalyst was characterized by SEM,TEM,FT-IR,XRD,31 P MAS-NMR and XPS.The results of SEM,TEM and XPS characterization show that CeFe x O y is wrapped by SiO 2 to form core-shell nanocomposite material.The Keggin-type structure is retained after being loaded by HPMo-H 2 O 2 and a little peroxophosphomolybdate active species are produced in this process.The active order of different catalysts on the adsorption and oxidation desulfurization presents as the following:HPMo-H 2 O 2/CeFe x O y@SiO 2>CeFe x O y@SiO 2>CeFe x O y.The introduction of HPMo greatly improves the adsorption activity of organic sulfides,especially its remarkable performance in oxidative desulfurization.The improvement of the performance in oxidative desulfurization is due to the“pseudo-liquid phase”reaction process of polyoxometalate.The dibenzothiophene(DBT)oxidation removal rate reaches 99.4%under such conditions:m(oil)∶m(catalyst)=35∶1,n(H 2 O 2)∶n(S)=10∶1 at 60℃for 3 h.The prepared magnetic core-shell oxidative-desulfurization catalyst has ideal recycling performance for oxidative removal of DBT.HPMo-H 2 O 2/CeFe x O y@SiO 2 catalyst becomes a kind of environmental-friendly catalysts with simple preparation method,high catalytic activity and good stability.

关 键 词：吸附-氧化脱硫 磷钼酸 铈铁纳米复合氧化物 二苯并噻吩 

分 类 号：O643[理学—物理化学]