Modeling electrolytic transport for systems with concentration gradients, Ohmic resistance and electrochemical reactions

Abstract

This paper describes a two-dimensional multi-component electrolytic transport model that calculates the electric field by applying electroneutrality as an upper bound. This approach avoids directly enforcing electroneutrality in mass transport calculations or using Poisson’s equation. The two coupled equations of this model were numerically solved for cases with no convection. The transport equation was solved using a modified Control Volume method and a Peclet number. The electric field equation was discretized using the finite difference method and solved using the Alternating Direction Implicit method. The model’s results were compared with free-diffusion liquid junction data. Comparisons were also made with one-dimensional transport models. The model was then used to simulate two-dimensional scenarios without prescribed current distributions. The simulations agreed with the comparison data. Hence, the model shows promise in its ability to simulate two-dimensional multi-component electrolytic transport with concentration gradients, Ohmic resistance, and electrochemical reactions.

Keywords

• Electrolytic transport
• electrochemical reactions, control volume method