Sidorova M, Ermakova L, Kiprianova A, Aleksandrov D, Timofeev S
Department of Colloid Chemistry, St. Petersburg State University, 198504, St. Petersburg - Petrodvoretz, Universitetskiy pr., 26, Russian Federation.
Adv Colloid Interface Sci. 2007 Oct 31;134-135:224-35. doi: 10.1016/j.cis.2007.04.024. Epub 2007 May 5.
Equilibrium parameters (ion-exchange capacity, moisture content) and transport characteristics (electroconductivity, ion transport numbers, liquid filtration coefficient, and streaming potential) of perfluorinated sulfonated (MF-4SK) and carboxylated (MF-4CK) cation-exchange membranes in NaCl and KCl solutions were measured. Experimental data were used for calculation of the electrochemical membrane characteristics: concentration of fixed ions, counter- and coions, efficiency coefficients and structural resistance coefficients, ion mobilities in membranes, electroosmotic mobility and convective part of specific conductivity of intramembrane liquid, Donnan's potentials and water transport numbers in membranes. Concentration polarization of the membrane systems was also investigated. Method of limiting current determination - using polarization potential measurements after current interruption (DeltaE j=0) - was proposed and compared with usual (from current-voltage curve) method. Two components of DeltaE j=0 potentials -- connected with electrolyte diffusion (slow part) and connected with volume charge in diffusion layer (fast part) were determined. Electrolyte concentrations near membrane surfaces were calculated from the slow part of membrane polarization potentials in dependence on current density values.
测量了全氟磺酸化（MF-4SK）和羧基化（MF-4CK）阳离子交换膜在NaCl和KCl溶液中的平衡参数（离子交换容量、含水量）和传输特性（电导率、离子迁移数、液体过滤系数和流动电位）。实验数据用于计算电化学膜特性：固定离子、反离子和共离子的浓度、效率系数和结构阻力系数、膜中离子迁移率、膜内液体比电导率的电渗迁移率和对流部分、唐南电位和膜中的水传输数。还研究了膜系统的浓差极化。提出了使用电流中断后极化电位测量（DeltaE j=0）来确定极限电流的方法，并与常用的（从电流-电压曲线）方法进行了比较。确定了DeltaE j=0电位的两个分量——与电解质扩散相关的（慢部分）和与扩散层中体电荷相关的（快部分）。根据膜极化电位的慢部分，结合电流密度值，计算了膜表面附近的电解质浓度。
