摘要:本文采用循环伏安法(CV)研究了不同孔隙率的聚对苯二甲酸乙二醇酯(PET)空白膜支撑的液/液界面上的离子转移行为,包括简单离子转移(TEA+ 和ClO4-)和加速离子转移(DB18C6加速K+)。实验结果表明:由于孔隙率较小的空白PET膜支撑的水/1,2-二氯乙烷(W/DCE)界面具有不对称扩散场的特点,而孔隙率较大的空白PET膜支撑的W/DCE界面具有对称扩散场的特点,因此,在不同孔隙率的PET空白膜支撑的W/DCE界面上,同一离子的转移行为呈现出不同的CV曲线形状,即对称和不对称。
根据Amatore 和Dryfe提出的计算扩散场重叠系数的经验公式: ,计算了不同孔隙率PET膜支撑W/DCE扩散场的Kλ1/2值,并将计算值与实验得到的CV曲线形状进行比较,发现两者基本一致,即:当Kλ1/2大于10时,出现的CV曲线为对称的峰形曲线;当Kλ1/2小于10时,出现的CV曲线为稳态。7861
上述实验结果表明:离子在PET膜所支撑的液/液界面上的转移行为受膜孔隙率的影响。本工作有望根据大量的实验数据,通过构建物理和数学模型,数值拟合出不同孔隙率PET空白膜支撑的液/液界面上离子转移反应的CV曲线。
关键词: PET膜;液/液界面;离子转移;循环伏安法;孔隙率
Studies on the Ion Transfer across the Liquid/Liquid Interface Supported by PET Membrane
Abstract:In this paper, the ion transfer behaviors including simple ion transfer and facilitated ion transfer across the liquid/liquid interface supported by PET membranes with different porosity(γ) were studied by cyclic voltammetry. The experimental results show that the ion transfer behavors across the liquid/liquid interface supported by the bare PET membrane with different porosity present different CV curves, namely asymmetry and symmetry. All above results demonstrate that the liquid/liquid (W/DCE) interface supported by bare PET with low porosity has an asymmetric diffusion field. However, the liquid/liquid (W/DCE) interface supported by the bare PET with large porosity has a symmetric diffusion field.
According to the normalized geometric parameter Kλ1/2 proposed by Amatore and Dryfe, the different value of Kλ1/2 for the ion transfer across the liquid/liquid interface supported by the bare PET membrane with different porosity are calculated. The results completely agree to the theory proposed by Amatore and Dryfe, namely, a symmetrically peak-shaped (a single liner diffusion field) CV curve is obtained if Kλ1/2>10. A sigmoidal (non-interacting radial diffusion fields) voltammogram is observed when Kλ1/2﹤10.
All above results demonstrate that ion transfer and facilitated ion transfer behaviors across the oil/water interface supported by the bare PET are closely related with the porosity of the PET membrane.This work is helpful to build a mathematical model based on a large number of experimental data and simulate CV curve of ion transfer and facilitated ion transfer across the oil/water interface supported the bare PET membrane with different porosity.
KeyWords: PET membrane; Liquid/liquid Interface; Ion transfer; Porosity; Cyclic voltammetry
目录
1引言 1
1.1 课题目的 1
1.2 选题研究现状及发展趋势 2
1.2.1 不同种类的液/液界面的介绍 2
1.2.2 液/液界面电化学的最新进展 4
1.2.3有机多孔膜支撑的膜液∕液界面 4
1.2.4 理论基础 6
2实验部分 7
2.1 仪器与试剂 7
2.1.1 仪器 7
2.1.2试剂 8
2.1.3 试剂的配制 8
2.2 实验内容 9
2.2.1以膜所支撑的液/液界面的制备以及电化学检测 9 PET空白膜支撑的液液界面上的离子转移反应的研究:http://www.youerw.com/huaxue/lunwen_5976.html