DSA类电极催化降解硝基苯动力学及机理的研究

用新兴的电化学催化系统,以特殊工艺自制的DSA类电极作阳极,对模拟硝基苯废水进行了降解处理,得出了该试验范围内的最佳条件,降解过程符合一级反应模型.根据分析,推测硝基苯分子主要先被阴极产生的H还原为亚硝基苯、苯胺等,然后再扩散到阳极附近被HO*氧化为偶氮苯、氧化偶氮苯等,最后进一步氧化开环,生成苯基丁二酸等酸类物质以至二氧化碳,同时硝基苯分子也可以直接在阳极附近得到氧化生成2-硝基苯酚.最后,对硝基苯的降解途径进行了描述. 

Study on Catalytic Degradation Kinetics and Mechanism of Nitrobenzene Wastewater Using DSA-Type Anodes

Dimensionally stable anodes (DSA)-type anodes,made by the authors themselves with special technology, have been employed in electrochemical catalytic system,one of the newly developed advanced oxidation technologies/processes(AOT/P),to treat the nitrobenzene wastewater.The optimal condition has been obtained in this study range.The analysis shows that the reaction can be described by first-order kinetics.It is inferred that nitrobenzene molecules will be mainly reduced by H· produced on the cathodes firstly to form nitrosobenzene and aniline,etc.,which diffuse to the anodes to be oxidized by HO· absorbed on the anodes surface to give azobenzene and azoxybenzene,etc.and at last the benzene rings will be opened to produce acid and carbon dioxide.The analyses also imply that nitrobenzene molecules can be oxidized around the anodes directly to form 2-nitrophenol.Finlly,the degradationpathways of nitrobenzene have been illustrated.