摘要:本课题以阴离子交换膜作为新型的模板支撑液/液界面,并研究该界面上电荷选择性离子转移反应过程。通过扫描电镜对三种阴离子交换膜进行形貌表征,结果表明:聚乙烯异相阴离子交换膜具有最大厚度,约为400um,均相聚四氯乙烯阴离子交换膜的厚度约为200um,聚乙烯接枝聚苯乙烯碱性强碱阴离子交换膜的厚度最小,只有140um。另外,考察不同阴离子交换膜作为模板支撑液/液界面的电化学窗口,实验结果表明:由于聚乙烯异相阴离子交换膜和均相聚四氯乙烯阴离子交换膜的膜厚度太大,难以形成理想的电化学窗口,聚乙烯接枝聚苯乙烯碱性强碱阴离子交换膜可以形成稳定的、超宽的(0.2V-1.8V)电化学窗口。
另外,研究聚乙烯接枝聚苯乙烯碱性强碱阴离子交换膜作为模板支撑的液/液界面上的电荷选择性离子转移反应过程,结果表明:高氯酸根、硫酸根、硝酸根阴离子在在该界面上可以发生转移。高氯酸根出峰位置是在0.30V和0.70V;硫酸根出峰位置是在0.32V和0.75V;硝酸根出峰位置是在0.26V和0.74V,然而,在该界面上无法观察到易于发生离子转移的阳离子TEA+的转移现象。上述结果表明:阴离子交换膜可作为新型的支撑材料修饰液/液界面,该界面具有很宽的电化学窗口和优异的电荷选择性,有望将其应用于离子的电荷选择性膜萃取和分离。9098
关键词: 阴离子交换膜;液/液界面电化学;无机阴离子;电荷选择性;离子转移
Studies on the Charge-Selective Ion Transfer Behaviors at the Liquid /Liquid Interface Supported by Anion-Exchange Membrane
Abstract: In this work, anion-exchange membranes (AEM) were firstly applied to support liquid/liquid (L/L) interface and to study the charge-selective ion transfer. Three different anion exchange membrane were adopted in this study, which were firstly characterized by scanning electron microscope (SEM). SEM results show that the membrane thickness of Polyethylene-heterogeneous anion exchange membrane is about 400um, and the thickness of PCE-homogeneous anion exchange membrane anion exchange membrane is about 200um, while the thickness of phenylethylene-polyethylene anion exchange membrane is minimum among above three membranes, which is about 140um.
In addition, the electrochemical experiment results show that the L/L interfaces supported by phenylethylene-resin-polyethylene or PCE-homogeneous anion exchange membranes can not provide ideal electrochemical window, while the L/L interfaces supported by phenylethylene-polyethylene anion exchange membrane can provide ideal electrochemical window with large range.
Moreover, Charge-selective ion transfer behaviors across the L/L interfaces supported by phenylethylene-polyethylene anion exchange membrane were investigated. The results show that the peak potential for the transfer of perchlorate from aqueous phase to organic phase is also at 0.30V,and its reverse transfer from organic phase to aqueous phase appears at 0.70V. The peak potential for the transfer of sulfate from aqueous phase to organic phase is at 0.32V,and its reverse transfer appears at 0.75V. The peak potential for the transfer of nitrate from aqueous phase to organic phase is at 0.26V,and its reverse transfer appears at 0.74V. Significantly, the cation TEA+ with low Gibbs transfer energy can not transfer across such an anion-exchange-membranes-support liquid/liquid (L/L) interface. All above results indicate that anion exchange membrane can be applied to support liquid/liquid interface with large electrochemical window and high charge-selectivity, which can be further applied in membrane-based charge-selective ion extraction and separation.
Keywords: Anion exchange membrane; Liquid/liquid interface; Inorganic anions; Charge selectivity; Ion transfer
目录
1前言及绪论 1
1.1 选题研究现状及发展趋势 1 阴离子交换膜支撑液液界面上的选择性离子转移反应的研究:http://www.youerw.com/huaxue/lunwen_7698.html