负载型三维电极处理甲基橙废水的动力学和降解机理研究  

Investigation on Kinetics and Degradation Mechanism of Methyl Orange Wastewater Treatment Using a Supported Three-Dimensional Electrode

作　　者：徐孟晓 胡俊生[1] XU Mengxiao;HU Junsheng(School of Municipal and Environmental Engineering,Shenyang Jianzhu University,Shenyang Liaoning 110168,China)

机构地区：[1]沈阳建筑大学市政与环境工程学院,辽宁沈阳110168

出　　处：《辽宁化工》2024年第8期1173-1180,共8页Liaoning Chemical Industry

摘　　要：采用化学共沉淀法制备负载型Fe_(3)O_(4)-MnO_(2)/GAC粒子电极,通过三维电极系统处理甲基橙废水,探讨甲基橙和COD降解的反应动力学,并运用紫外-可见光光谱分析甲基橙的降解机理。结果表明:降解甲基橙和COD反应均为一级反应,粒子投加量为50 g·L^(-1),溶液p H为7,溶液温度为45℃时反应速率常数最大,降解甲基橙和COD的反应活化能分别为3.4442×10^(4)J·mol^(-1)和1.5299×10^(4)J·mol^(-1)。此外,根据紫外-可见光光谱推测甲基橙降解机理为偶氮式降解,强氧化物与甲基橙接触首先破坏发色基团,并且破坏偶氮键分解为多种芳香类物质;接着·OH进一步攻击苯环大π键,生成苯酚、对苯二酚等中间产物,最终被矿化为CO_(2)和H_(2)O。The Fe_(3)O_(4)-MnO_(2)/GAC particle electrode was prepared by chemical coprecipitation method.The reaction kinetics of methyl orange and COD degradation was studied by using three-dimensional electrode system.The degradation mechanism of methyl orange was analyzed by UV-visible spectrum.The results showed that both the degradations of methyl orange and COD were first-order reactions,and the reaction rate constant was maximum when the particle dosage was 50 g·L^(-1),the solution pH was 7 and the solution temperature was 45.The activation energies of the degradation of methyl orange and COD were 3.4442×10^(4)J·mol^(-1)and 1.5299×10^(4)J·mol^(-1),respectively.In addition,according to UV-visible spectrum,the degradation mechanism of methyl orange was estimated to be azo degradation.The contact between strong oxides and methyl orange first broke the cyclic chromophore group and broke the azo bond to decompose into various aromatic substances.Then·OH further attacked the largeπbond of the benzene ring,forming intermediates such as phenol and hydroquinone,which were finally mineralized into CO_(2)and H_(2)O.

关 键 词：三维电极 甲基橙 COD 动力学 

分 类 号：X791[环境科学与工程—环境工程] TQ613.1[化学工程—精细化工]