DSA电极电催化氧化降解四环素废水工艺优化

以盐酸四环素(TC·HCl)为研究对象,钛基钌铱涂层(IrO2-RuO2/Ti)为阳极,钛板为阴极,电催化氧化降解TC·HCl模拟废水,探讨了初始质量浓度、电流密度、pH、电解质硫酸钠浓度对电催化降解TC·HCl效率的影响。结果表明,电催化氧化可有效降解水中的TC·HCl。提高电流密度,降低TC·HCl初始质量浓度、电解质硫酸钠浓度,可增大TC·HCl去除率。反应的前90 min,pH对去除率无影响,反应90 min后降解效果出现明显差别,pH为3、7和12时,反应300 min去除率分别为92%、100%和72%。降解过程遵循一级反应动力学模型。通过综合各工艺参数下的去除率、能量消耗和电流效率,得出最佳工艺参数为:TC·HCl初始质量浓度300 mg/L、电流密度10 mA/cm2、硫酸钠浓度0.05 mol/L、pH=7,在该条件下反应180 min后TC·HCl去除率达94%。该实验结果为电化学处理制药工业废水提供了基础数据和科学参考。

Optimization of Electro-catalytic Oxidation of Tetracycline Hydrochloride in Aqueous Solution by DSA Electrodes

Tetracycline HCl (TC•HCl) in an artificial wastewater was electrochemically degraded using IrO2-RuO2/Ti as anode and Ti as cathode. The impacts of initial TC concentrations, current density, pH value, electrolyte concentrations on the degradation effect of TC were investigated. The energy consumption and current efficiency were compared according to operating conditions to reveal the optimal condition for electrochemical degradation of TC HCl. Results showed that electro-catalytic oxidation could effectively remove TC in aqueous solutions. Higher current density, lower initial concentrations of TC•HCl and/or lower concentrations of Na2SO4 as electrolyte could enhance the removal rate of TC•HCl. During 0-90 min of the reaction, pH had no effect on the removal rate. After 90 min, acidic and alkaline conditions both partly inhibited the degradation of TC HCl, for example, the removal rates at pH 3, 7 and 12 were 92 %, 100 % and 72 % after 300 min respectively. Degradation procedure was in accordance with the first-order kinetic model. With the analysis of the removal rate, energy consumption and current efficiency under various operating conditions, the optimal condition constitute the initial TC•HCl concentration of 300 mg/L, the current density of 10 mA•cm-2, the Na2SO4 concentration of 0.05 mol•L-1 and the pH value of 7 with a removal rate of TC•HCl 94 % after 180 min. The present study provides so far the primary data for wastewater management against TC HCl.