重量法研究非离子表面活性剂对典型挥发性有机污染物的增溶作用

WEIGHT METHOD FOR THE DETERMINATION OF SOLUBILIZATION OF TOLUENE BY NONIONIC SURFACTANTS

采用重量法研究了典型非离子表面活性剂(Tween-20、Tween-40、Tween-60、Tween-80)对以甲苯为代表的挥发性有机污染物(VOCs)的增溶作用.通过计算甲苯在初始和平衡状态的质量变化,确定甲苯在表面活性剂中的增溶量,比较了重量法与传统紫外分光光度法的测定结果,并计算分析4种表面活性剂增溶作用下甲苯表观亨利系数随浓度的变化.结果表明,重量法所测表面活性剂对甲苯的溶解量在临界胶束浓度(CMC)附近出现明显变化,且与传统表观溶解度测定结果的线性相关系数达到0.99以上.重量法测定过程简单,避免了紫外分光光度法分析过程中由于某些表面活性剂的颜色过深或浓度太大对分析造成严重干扰.因此,重量法测定表面活性剂对VOCs的增溶作用是可行的.

In the process of determining the solubilization ability of surfactants by conventional ultraviolet spectrophotometry,the interference can be caused by the surfactants with deep color,and the steps are always complicated.In this paper,the solubilization action of a typical volatile organic compound toluene by nonionic surfactants Tween-20,Tween-40,Tween-60 and Tween-80 through weight method was studied.The solubilization capacity was calculated based on the changes of quality of target compounds,and then the results were compared with those of the traditional method with spectrophotometer.The impact on Apparent Henry coefficient of toluene by the surfactant concentrations were also analysed.The results showed that surfactant solutions had remarkable solubilization ability when the concentrations of surfactants were above the critical micelle concentration（CMC）,the data of these two methods were nearly identical and all the correlation coefficients were above 0.99.The weight method is convenient,and it avoids the interference of the deep color of some surfactants in the analysis of solubilization ability by the conventional approach.So this method could be one of the simple and feasible solutions to determination of solubilization.