不同晶型MnO_(2)的制备及其催化甲苯燃烧性能研究  

Preparation of MnO_(2) with different crystal phases and catalytic performance in toluene combustion

作　　者：李醒龙 宋微娜 李硕 温治斌 LI Xinglong;SONG Weina;LI Shuo;WEN Zhibin(School of Environmental and Chemical Engineering,Heilongjiang University of Science and Technology,Harbin 150022,China)

机构地区：[1]黑龙江科技大学环境与化工学院,哈尔滨150022

出　　处：《黑龙江大学工程学报(中英俄文)》2024年第4期21-29,共9页Journal of Engineering of Heilongjiang University

基　　金：黑龙江省自然科学基金项目(LH2022F051);国家自然科学基金项目(51974113)

摘　　要：通过醇还原和水热法制备了4种晶型的MnO_(2)催化剂,并考察MnO_(2)晶型结构调控对催化剂催化氧化甲苯性能的影响。利用XRD、SEM、N2吸附-脱附、TPR、TPD等技术手段对MnO_(2)催化剂进行结构表征与分析,并通过催化氧化甲苯的转化率评估材料对甲苯的催化性能的影响。结果表明具有α、β、γ和δ晶型结构的MnO_(2)催化剂表现出差异较大的形貌特征和表面性质。乙二醇还原法制备的α-MnO_(2)具有更多表面缺陷活性位点,平衡了活化表面晶格氧和Mn4+离子的协同比例,有利于催化氧化甲苯反应。甲苯转化率达50%和90%时,α-MnO_(2)催化剂的催化氧化温度降低至210℃和219℃。可为过渡金属Mn系催化剂的制备及高效绿色应用提供参考。Four kinds of crystalline MnO_(2) catalysts were prepared by alcohol reduction and hydrothermal method,and the effect of MnO_(2) crystal structure regulation on the catalytic oxidation of toluene was investigated.The structure of MnO_(2) catalyst was characterized and analyzed by XRD,SEM,N2 adsorption⁃desorption,TPR,TPD and other technical means,and the catalytic performance of the material to toluene was evaluated by the conversion rate of toluene catalytic oxidation.The results show that MnO_(2) catalysts withα,β,γandδcrystal structures show different morphological characteristics and surface properties.Theα⁃MnO_(2) prepared by ethylene glycol reduction method has more surface defect active sites,which balances the synergistic ratio of activated surface lattice oxygen and Mn4+ions,and is beneficial to the catalytic oxidation of toluene.When the toluene conversion reached 50%and 90%,the catalytic oxidation temperature ofα⁃MnO_(2) catalyst increased to 210℃and 219℃.The result can provide a reference for the preparation and efficient green application of transition metal Mn⁃based catalysts.

关 键 词：醇还原 晶型 催化氧化甲苯 锰氧化物 

分 类 号：TQ426.61[化学工程]