填充床电催化氧化工艺处理甲基橙废水实验研究

Electro-oxidation of Wastewater Containing Methyl Orange by Activated Carbon Packed-bed Electrode Reactor

以甲基橙模拟废水为降解对象,研究了填充床电化学反应器对偶氮燃料废水的电催化降解特性;结果表明初始浓度450mg/L,电解质含量为2%的甲基橙废水在30A/m2电流密度下经180min降解出水甲基橙浓度为2.93mg/L,去除率达99.3%,UV分析表明降解过程以键裂解为主,无其他大分子组分生成,其浓度变化符合一级动力学降解模型;在此基础上,采用单因素变量实验方法研究了初始甲基橙浓度、电流密度、电解质含量及进水流速对甲基橙电催化过程中动力学常数k的影响,得到各因素控制下动力学常数的数学表达式。依据一级动力学模型给出填充床电化学反应器处理甲基橙废水的浓度预测方程,以其通过电化学反应操作条件的优化实现甲基橙废水的彻底降解或对出水甲基橙浓度的准确预测。

A bench scale experiment was described,in which a packed-bed electrode reactor filled with granular activated carbon was employed to the purification of wastewater containing methyl orange（MO）,a kind of azo dyes. The experimental results showed that removal rate of MO could reach 99.3% and its degradation in terms of concentration was from 450mg/L down to 2.93mg/L in 180min when electrolyte content and current density were adequately adjusted. UV analysis indicated that bond breakage may take place but no macromolecular organic matters were formed during the electro-catalysis process,also the change of methyl orange concentration followed the first order kinetics model. Accordingly,further study were conducted using a single-factor experimental method to investigate the parameters of initial methyl orange concentration,electrolyte content,current density and flow rate on the effect of kinetic constant（k） during the methyl orange electric-catalytic process. By doing this,expressions that could explain the relationship between the factors above with k was given.Finally,an empirical model for methyl orange degradation by packed-bed electrode reactor was proposed for the purpose of complete breakdown of MO or predicting the MO concentration in the effluent under the optimum operating condition.