Simultaneous Transfer of Two Metal Ions across Cation Exchange Membrane

抄録

The transfer rates of two metal ions across a cation exchange membrane were measured for the systems Na⁺–K⁺, Na⁺–Mg²⁺ and Na⁺–Ca²⁺. The ion exchange equilibrium was also measured for these systems. The distribution ratio of metal ion between aqueous phase and membrane phase for a system of two metal ions could be estimated with the ion exchange equilibrium constants obtained for the system of a single metal ion. The permeation rates of metal ions across the membrane were calculated by a model based on the nonequilibrium exchange kinetics at the membrane surface, which was in good agreement with the experimental results. The permeation selectivity of ion, which might depend on the ion exchange rate at both surfaces of the membrane, differed largely with the selectivity by the ion exchange equilibrium.