微波诱导催化反应在环境净化中的应用研究进展

Applying Microwave-induced Catalytic Reaction to Environmental Purification:a Review

催化净化法是环境污染物的主要净化技术之一,而微波场具有波动性、高频性、热特性和非热特性四大基本特征,因此微波诱导催化反应在改善环境质量方面具有至关重要的作用。随着科研人员对微波技术以及催化技术不断深入的研究,开发具有优异吸波性能与催化活性的多功能材料成为研究的重点。根据吸波材料转化微波的形式可以将吸波材料分为介电损耗型、电阻损耗型和磁损耗型。吸波材料的吸波性能受到材料组成、表面构型、孔径结构等多种因素的影响。近年来,研究者们从材料的匹配特性与衰减特性出发,不断改进吸波材料合成方法,并取得了丰硕的成果,在不断改善材料吸波性能的同时,充分发挥其在微波诱导催化反应中的作用,提高了能源利用率以及环境污染物的降解速率。吸波材料在微波的作用下会产生热点效应以及放电效应。微波诱导催化反应将常规热场改为微波热场,可以在较低的宏观温度下实现材料的迅速升温,达到优异的催化效果。金属材料在微波场中会诱发微波放电,放电过程会产生热点效应、等离子体效应以及光催化效应,对污染物的去除具有重要作用。但由于微波诱导催化的反应过程较为复杂,当前的研究难点为区分热点效应与放电效应的影响、明确微波诱导催化反应的反应路径。近年来研究者们开发了一系列具有优异吸波性能以及催化效能的催化剂,将微波诱导催化反应应用于废水废气的净化处理技术,具有反应速率快、处理效率高等优点。本文主要介绍了材料的吸波原理,阐述了材料吸波性能的改进、微波热点效应和微波放电效应在污染物去除方面的应用,并对微波诱导催化反应今后的发展方向进行了讨论。

Catalytic purification has been developed to be a main technology involving with the removal of environmental pollutants.Microwave(MW)radiation with excellent performances of volatility,high frequency,thermal and non-thermal characteristics has caused widely attention.Therefore,MW-induced catalytic reactions play a vital role in improving environmental quality.With the continuous in-depth research of MW radiation and catalytic technology,the development of multifunctional materials with excellent MW absorbing performance and catalytic activity has become the focus of studies.According to the way of transforming the MW,wave-absorbing materials can be divided into three types,including dielectric loss,resistance loss and magnetic loss.The absorbing performance of the wave-absorbing materials is affected by various factors such as element composition,surface configuration and pore structure.In recent years,researchers have been improving the synthetic methods of wave-absorbing materials from the matching and attenuation characteristics,and have achieved substantial progress in enhancing the MW absorbing properties of mate-rials,and making full use of MW-induced catalytic reactions to improve the energy utilization rate as well as the degradation rate of environmental pollutants.Wave-absorbing materials will produce hot spot effect and discharge effect in the MW field.The MW-induced catalytic reaction changes the conventional thermal field to MW heating,which can realize the rapid temperature rise of the material at a lower environment temperature and achieve excellent catalytic performance.Metal materials can induce MW discharge in the MW field,and the discharge process will produce thermal effect,plasma effect and photocatalytic effect,which plays a crucial role in pollutant removal.However,since the reaction process of MW-induced cata-lysis is complicated,current studies have focused on distinguishing the influence of heat spot effect and discharge effect and clarifying the reaction pathway of MW-induced catalysis.Over the past years,a variety of catalysis with outstanding wave-absorbing and catalytic performances has been developed,and applied the MW-induced catalytic reaction to the purification treatment technology of waste water and exhaust gas,which has the advantages of fast reaction rate and high treatment efficiency.This paper mainly introduces the principle of MW absorption of materials,expounds the improvement of MW absorption properties of materials and the application of MW hot spot effect and discharge effect in pollutant removal,and discusses the future development direction of MW-induced catalytic reactions.