超声波与氯胺联用工艺去除水中三氯生的研究

Degradation of triclosan in aqueous solution by using ultrasound combined with chloramine

采用超声与氯胺联用工艺对水中三氯生(TCS)的去除进行了研究,考察了超声功率、氯胺投加量、TCS初始浓度、p H值和自由基捕获剂等因素对TCS去除的影响,鉴定识别了降解产物并探讨联用工艺降解TCS的机理.结果表明,超声和氯胺联用去除TCS具有协同效应,可以有效地去除TCS.超声波功率为600W,TCS浓度为200μg/L,氯胺浓度为5mg/L时,120min后TCS去除率可达90.8%.联用工艺中增加超声功率可以提高TCS的去除,TCS的去除率随氯胺浓度升高呈现出先升高后降低的趋势,随着初始浓度的升高而下降,碱性环境有利于TCS的去除,p H值为10.7时,TCS的去除可达100%,自由基捕获剂叔丁醇TBA对TCS的去除有抑制作用.GC/MS扫描分析表明2,4-二氯苯酚(2,4-DCP)为TCS的降解产物.

Ultrasound and chloramine combined process was employed in this paper to remove triclosan （TCS） in aqueous solution. The effects of several factors such as ultrasonic power, chloramine dosage, TCS initial concentration, pH and radical scavenger on TCS degradation were studied. Furthermore, the degradation products were identified and the degradation mechanism of TCS by combined process was discussed. The results indicated that the combination of ultrasound and chloramine can remove TCS effectively and possess significant synergetic effect on the degradation. The degradation rate of TCS could reach 90.8% within 120min under the conditions of ultrasonic power 600W, TCS initial concentration of 200μg/L, and chloramine dosage of 5mg/L. TCS degradation efficiency decreased with the raise of initial concentration of TCS, and tended to increase firstly and then decrease with the increase of chloramine concentration. Alkaline environment was conducive to the TCS removal, and the degration efficiency of TCS could reach 100% when pH value was 10.7. The presence of free radical scavenger TBA had an inhibitory effect on TCS degradation. The identification and recognition of degradation products by GC/MS indicated 2,4-dichlorophenol （2,4-DCP） was the main degradation products of TCS during the combined process.