LDPE膜被动采样技术预测模型的建立及其应用

选用3种厚度的低密度聚乙烯(LDPE)膜(76,56和25μm)作为研究对象,对辛醇-水分配系数的对数(logKow)>2的有机污染物采用被动采样技术进行膜-水分配系数(Kpew)实测实验和动力学实验,首次建立考虑时间(t),膜厚度(d)和动力学3个因素的LDPE膜 Kpew预测模型.实验结果表明,预测模型得到的Kpew与实测Kpew的相对误差为±0.03,证明了预测模型的准确性和可靠性.Kpew预测模型的建立避免了实验监测Kpew的繁琐实验过程,从而极大地提高了有机污染物的监测效率.将预测模型Kpew值应用于浑河与东洲河有机污染物质的监测,监测结果进一步表明了预测模型的准确性和实用性.此外本文首次提出了苯系物的Kpew值,对LDPE膜被动采样技术应用的延伸属于突破性进展.

The establishment and application of predict model for passive sampling technique with LDPE membranes

To obtain membrane water partition coefficient , Kpew, practical tests and kinetic experiments were conducted using passive sampling technique with three different thickness (76μm,56μm and 25μm) of low-density polyethylene (LDPE) membranes. For organic pollutants with logarithmic of octanol-water partition coefficient, logKow, greater than 2, the prediction model for Kpew has been established considering three key factors of time (t), thickness of film (d) and kinetics. The results shown that the relative error between Kpew from practical tests and prediction model is ±0.03, which proved the precise and reliable of this prediction model. The establishment of prediction model for Kpew could avoid the complicated processes of Kpew practical monitoring, hence the monitoring efficiency of organic pollutants would be improved significantly. Furthermore, the prediction model was applied to monitoring the organic pollutants in river Hun and Dongzhou, of which the results proved the precise and practicability of this prediction model in further. Besides, Kpew of benzene series are firstly proposed, which is considered as a breakthrough for the extension of passive technique with LDPE membranes.