二氧化锰基催化剂催化氧化甲苯的进展

Advances in the Catalytic Oxidation of Toluene by MnO_(2)-based Catalysts

随着我国产业升级和能源消费的增加,甲苯污染已成为一个重要的环境问题。现有甲苯处理方法中,催化氧化技术无疑是最为经济且有效的技术手段。而作为催化反应核心的催化剂,其性能尤为重要。贵金属催化剂虽然拥有活性优势,但烧结、毒化带来的活性下降以及高昂的价格阻碍了其在工业领域的广泛应用。过渡金属氧化物催化剂中,二氧化锰(MnO_(2))由于其高催化活性、热稳定性、价格低廉、易于合成以及多种晶体形态可用的特点,近年来在甲苯催化氧化领域备受关注。但单一MnO_(2)的催化活性很难令人满意,对其改性优化就成为当前工作的重点。本文分析了MnO_(2)的晶体结构、表面特性和特定晶面等结构特点对甲苯催化效率的影响,重点探讨了通过掺杂、复合以及负载等改性手段提升MnO_(2)催化氧化甲苯的性能,并阐述了甲苯在MnO_(2)上的催化氧化机理,对制备用于催化甲苯的新型MnO_(2)催化剂的未来研究方向进行了展望。

Owing to industrial development and increasing energy consumption in China,toluene pollution has become a serious environmental concern.Among the existing toluene treatment methods,catalytic oxidation is undoubtedly the most economical and effective technical approach.The performance of the catalyst,which is the core of the catalytic reaction,is particularly essential.Although noble metal catalysts possess excellent catalytic activity,their high cost and the decrease in activity due to sintering and poisoning hinder their widespread application in industry.In recent years,manganese dioxide(MnO_(2))has attracted much attention as a transition metal oxide catalyst for the catalytic oxidation of toluene owing to its high catalytic activity,thermal stability,low cost,and easy synthesis,as well as the availability of various crystal forms.However,the catalytic activity of single MnO_(2)is unsatisfactory,prompting the present study on its modification and optimization.We analyzed the effects of the structural characteristics of MnO_(2),such as the crystal structure,surface properties,and specific crystalline surfaces,on the catalytic efficiency of toluene.Further,we aimed to improve the performance of MnO_(2)for the catalytic oxidation of toluene through modification approaches like doping and composite loading and to elucidate the catalytic oxidation mechanism of toluene on MnO_(2).The direction of future research on the preparation of novel MnO_(2)catalysts for toluene catalysis is outlined herein.