新型铁炭微电解法降解EDTA有机废水

Degradation of organic wastewater containing EDTA by Fe-C micro-electrolysis

开发一种基于铁炭微电解处理有机废水的新方法,处理乙二胺四乙酸（EDTA）难降解有机废水。采用活性炭作氧电极载体,铁粉为阳极,在酸性富氧条件下产生的.OH自由基有效降解废水中的EDTA组分,根据微电池原理及Fenton反应导出羟基自由基.OH浓度的热力学关系式,可用于合理解释各种因素对EDTA脱除率的影响。研究pH、通气条件、温度、反应时间及Fe与C的质量比对EDTA脱除效果的影响,得到最佳工艺条件如下：pH为2~4,温度为常温,Fe与C的质量比≥0.01,时间〉30 min,有氧气存在,在该条件下使总有机碳（TOC）质量浓度为200 mg/LEDTA的脱除率达到83.8%。

A novel technique based on Fe-C micro-electrolysis（FAC） to treat the organic wastewater was proposed,which was used to treat EDTA-containing organic wastewater.In this study,activated carbon and iron were taken as the inert electrode and the cathode,respectively.EDTA in the wastewater could be degradated effectively by ·OH gemerated under the acidic and oxygen-rich conditions.The mechanism and influencing parameters of organic wastewater treatment by FAC were investigated.Thermodynamic relationship was deduced,which could be used to interpret all of the parameters effecting EDTA removal rate reasonably.The results show that the residual TOC is affected by pH of influent,dissolved oxygen DO,temperature,contact time and Fe/C mass ratio,and the conditions are as follows： pH is 2-4,room temperature,Fe/C mass ratio is more than 0.01,contact time is more than 30 min,and oxygen exists.Under the optimal conditions the removal rate of EDTA with 200 mg/L concentration can reach 83.8%.