改性WO_3/ZrO_2催化剂上偏三甲苯异构化  

Isomerization of 1,2,4-trimethylbenzen over modified WO_3/ZrO_2 catalysts

作　　者：周婷[1] 陈晓蓉[1] 陈长林[1] 

机构地区：[1]南京工业大学化学化工学院材料化学工程国家重点实验室,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2008年第3期21-25,共5页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(20476047)

摘　　要：通过浸渍法制备了系列负载Ni以及掺杂碱土金属(Mg、Ca、Sr、Ba)改性的WO3/ZrO2催化剂,采用XRD和NH3-TPD方法表征了催化剂表面物相结构及酸性,考察了负载Ni以及掺杂碱土金属对偏三甲苯异构化反应的催化性能的影响.结果表明,WO3/ZrO2中引入Ni,使催化剂由单一的酸中心催化变成由酸中心与金属中心共同催化;碱土金属的添加增强了WO3与ZrO2之间的相互作用,适量地降低了催化剂的酸性位,有效抑制了主要副反应歧化反应的发生.A series of WO3/ZFO2 catalysts modified by Ni and alkaline-earth metals, such as Mg, Ca, Sr or Ba were prepared by the impregnation method. The structure and surface acidity of the catalysts were characterized by X-ray powder diffraction （XRD） and NH3temperature-programmed desorption （NH3-TPD）. The catalytic performance of the samples for 1,2,4-trimethylbenzen isomerization was also studied. As Ni addition to alkaline-earth metals modified WO3/ZrO2 catalyst, NiMWZ catalysts exhibited the properties of metal-acidic bifunction. The addition of alka- line-earth metal can promote the interaction between tungsten oxide and zirconia and also decrease the acid sites of the catalyst, and the trimetylbenzene disproportionation was restrained.

关 键 词：氧化钨 氧化锆 镍 碱土金属 偏三甲苯 

分 类 号：TQ426[化学工程]