Abstract
The limiting current densities (ilim) for the cation and anion exchange membranes in diluted nickel plating solutions were measured by using a small electrodialysis cell. In the flow velocity range of 0.3 to 3.1cm/sec, a linear relationship was obtained between ilim and the flow velocity. In the nickel concentration range of 2.9 to 6.7g/l, the relationship between ilim and the nickel concentration was also linear, which agreed with Nernst-Planck's equation. The relationship between ilim and the temperature of the solution was best explained by using Arrhenius' equation. From the activation energy estimated by Arrhenius' equation, it was found that the change in ilim is mainly due to the temperature dependence of diffusion coefficient. In the mixture of sulfuric acid and diluted nickel plating solution, a linear relationship exists between [H+]/[Ni2+] and ilim of the cation exchange membrane, which agreed well with Rosenberg's equation.
