MnO_x催化氧化甲苯的构-效关系  

Structure-activity relationship for catalytic oxidation of toluene on MnO_x catalysts

作　　者：毛益萍 潘华 王晟康[1] 杨仲余 张鼎盛 施耀 MAO Yi-ping;PAN Hua;WANG Sheng-kang;YANG Zhong-yu;ZHANG Ding-sheng;SHI Yao(College of Biology and Environmental Engineering,Zhejiang Shuren University,Hangzhou 310015,China;College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]树人大学生物与环境工程学院,浙江杭州310015 [2]浙江大学化学工程与生物工程学院,浙江杭州310027

出　　处：《高校化学工程学报》2019年第6期1432-1436,共5页Journal of Chemical Engineering of Chinese Universities

基　　金：浙江省自然科学基金(LY19E080023);浙江树人大学中青年学术团队项目(XKJ0516205);浙江树人大学科研启动基金(KXJ0517102);国家级大学生创新创业训练计划项目(201811842020)

摘　　要：以甲苯为研究对象,通过水热合成法制备了一系列MnOx催化剂,结合催化活性评价和催化表征手段,考察了MnOx催化氧化甲苯的构-效关系。研究表明:在不同制备温度的MnOx催化剂中,催化活性的顺序为MnOx-70>MnOx-90> MnOx-120,MnOx-70催化剂具有最低的起燃温度(T50=196℃),其在256℃下甲苯的转化效率可稳定在90%。催化剂的活性与比表面积、孔体积、Mn3+/Mn4+和Olatt/Osurf的比值有关。催化剂的比表面积和孔体积大小为MnOx-70>MnOx-90>MnOx-120。催化剂中锰以Mn4+和Mn3+的形式存在,3种催化剂表面Mn3+/Mn4+的比值依次为MnOx-120>MnOx-90>MnOx-70。3种催化剂表面Olatt/Osurf的比值依次为MnOx-70> MnOx-90> MnOx-120。说明催化剂表面Mn4+和晶格氧含量越多,催化剂活性越好。Toluene was used as the model pollutant and various MnOx catalysts were prepared by hydrothermal synthesis. Structure-activity relationship for toluene oxidation catalyzed by MnOx was investigated via activity tests and catalyst characterization. The results show that MnOx-70 displays the highest activity with the lowest light-off temperature(T50 = 196 ℃) and toluene conversion of 90% at 256 ℃. Catalytic activity decreased in the order of MnOx-70 > MnOx-90 > MnOx-120. The catalytic activity was related to the specific surface area, pore volume, the ratio of Mn3+/Mn4+ and Olatt/Osurf. The specific surface area and pore volume of MnOx catalysts decreased as follows: MnOx-70 > MnOx-90 > MnOx-120. The active components of MnOx catalysts were Mn4+ and Mn3+. The ratio of Mn3+/Mn4+ on the surface of MnOx catalysts decreased in the order of MnOx-120 >MnOx-90 >MnOx-70. The Olatt/Osurf ratios on the surface of MnOx catalysts decreased as: MnOx-70 > MnOx-90 > MnOx-120. This study shows that Mn4+ and Olatt contents can promote the catalytic activity of MnOx catalysts.

关 键 词：催化氧化 锰氧化物 甲苯 构-效关系 

分 类 号：X511[环境科学与工程—环境工程]