高铁酸钾氧化去除水中三氯生的研究

Study on the degradation of triclosan in aqueous by potassium ferrate

采用高铁酸钾对水中三氯生(TCS)的去除进行了研究,探讨了TCS的降解机理,考察了高铁酸钾投加量、pH值、天然有机物(NOM)和双氧水等因素对TCS去除和中间产物2,4-二氯苯酚(2,4-DCP)生成的影响.结果表明:TCS通过醚键断裂降解生成2,4-DCP,TCS浓度为550μg/L,高铁酸钾浓度为15mg/L时,600s后TCS去除率可达96.48%.增加高铁酸钾投加量可以提高TCS的去除,TCS的去除率随pH值升高呈现出降低的趋势,酸性环境有利于TCS的去除,pH值为4时,TCS的去除达100%,腐殖酸和双氧水对TCS的去除有抑制作用.高铁酸钾可以有效降解TCS并降低溶液的急毒性,降低水质健康风险.

The degradation of triclosan (TCS) in aqueous by potassium ferrate was investigated, and the degradationmechanism of TCS was researched. Besides, the effects of different factors, such as potassium ferrate dosage, TCS initialconcentration, pH, natural organic matter (NOM) and hydrogen peroxide on TCS degradation and the 2,4-DCP formationduring potassium ferrate oxidation was specifically discussed. The results indicated that TCS was degraded into 2,4-DCPvia cleavage of the ether bond. The degradation rate of TCS could reach 96.48% within 600s under TCS initialconcentration of 550μg/L, and potassium ferrate dosage of 15mg/L. The oxidation of TCS was not a simultaneousdetoxification process. The degradation of TCS was showed positive correlation with the increase of potassium ferratedosage, but decreased with the increase of pH. Acid environment was conducive to the TCS removal, and the removal ofTCS reached 100% when pH value was 10.7. However, TCS removal was inhibited by the presence of NOM andhydrogen peroxide. Potassium ferrate can effectively degrade TCS, lower acute toxicity of reaction solution, and therefore,reduce health risk of water quality.