研究了NH4Cl在以多孔聚丙烯平板膜(Celgard2400)为支撑体、磷酸二(2-乙基己基)酯(D27EHPA)为膜液载体和煤油为膜溶剂的支撑液膜体系中的分离过程,采用交流阻抗法动态监测支撑液膜的膜液流失过程,这种方法的优点是可以连续实时监测支撑液膜的膜液流失.通过IM6电化学工作站测出了不同时间下的膜电阻来监测支撑液膜膜液流失的各个阶段,同时考察了影响膜液流失的一些因素.结果表明,膜电阻能够实时反映出膜液流失情况,原料相初始浓度降低和载体浓度增加均使液膜流失加快.
The separation of NH4Cl from feed solution into strip solution through supported liquid membrane (SLM) using Celgard2400 membranes as supports and D2EHPA dissolved in kerosene as a carrier was studied in this paper. The membrane liquid loss of SLM was dynamic monitored by electrical impedance spectroscopy. The advantages of this technique were non - invasive and capable of providing continuous monitoring of SLM membrane liquid loss. The impedances of SLM were measured along with elapsed time by IM6 electrochemical workstation. The changing rule of membrane impedance and the influence of operation conditions on the membrane liquid loss were also studied. The results showed that, the variation of membrane impedance could represent the behavior of membrane liquid loss in real time; the membrane liquid loss would be accelerated both by the decrease of the initial concentration of feed solution and by in real time the increase of the carrier concentration of membrane liquid.