掺杂方法对Cu-OMS-2催化氧化甲苯性能的影响  

Effect of doping methods of Cu-OMS-2 on catalytic oxidation of toluene

作　　者：陆义媛 孙敬雅 宁欣 万海勤[1] 许昭怡[1] 郑寿荣[1] 

机构地区：[1]南京大学环境学院污染物控制与资源化研究国家重点实验室,江苏省机动车尾气污染控制重点实验室,南京210023

出　　处：《环境化学》2017年第12期2627-2633,共7页Environmental Chemistry

基　　金：江苏省自然科学基金(BK20151381);国家重点研发计划(2016YFC0204301)资助~~

摘　　要：分别采用前掺杂法(PI)、离子交换法(IE)和浸渍法(IM)合成了过渡金属Cu掺杂的催化剂Cu-OMS-2,通过XRD、BET、XPS、H_2-TPR等手段对催化剂的结构进行表征,并测试催化剂对甲苯的催化燃烧性能.XRD结果显示,全部掺Cu样品与单纯OMS-2晶相峰相同;XPS结果表明,Cu掺杂有效调控了Mn^(3+)/Mn^(4+)的比例,催化剂表面形成不同数量氧空位,其中前掺杂法和离子交换法制备的催化剂表面生成了更多的氧空位;H_2-TPR结果显示Cu掺杂降低了催化剂还原温度,且前掺杂法和离子交换法制备的催化剂的还原温度低于浸渍法合成的样品.因此,前掺杂法和离子交换法合成的催化剂在甲苯催化氧化中显示出较高的催化活性.Cu-OMS-2 catalysts were synthesized by the methods of pre-incorporation（PI）,ion exchange（IE） and impregnation（IM）,respectively.The structures of the catalysts were characterized by X-ray diffraction（XRD）,N_2 adsorption/desorption（BET）,X-ray photoelectron spectroscopy（XPS） and H_2 temperature program reduction（H_2-TPR）.The catalytic performance of the catalysts for toluene combustion was investigated.The XRD results showed that all the Cu doped samples were identical to the pure OMS-2 crystal phase.The XPS results suggested that the ratio of Mn^（3＋）/Mn^（4＋） and the amounts of oxygen vacancies of the catalyst were adjusted by Cu doping.The amounts of oxygen vacancies in the Cu-OMS-2-PI and Cu-OMS-2-IE were higher than that of Cu-OMS-2-IM.H_2-TPR results indicated that the reduction temperature of OMS-2 decreased by Cu doping,and the catalyst prepared by PI and IE method showed a lower reduction temperature than the catalyst prepared by IM method.Therefore,the catalysts prepared by PI and IE method showed higher catalytic activities for toluene combustion than the catalyst prepared by IM method.

关 键 词：Cu-OMS-2 甲苯 催化氧化 掺杂法 离子交换法 浸渍法 

分 类 号：O643.32[理学—物理化学] X701[理学—化学]