Prediction of cathodic Cu~(2+) reduction in a laboratory filter-press electrolyser by computational fluid dynamics modelling

摘要

Cathodic electrodeposition of metal ions can be achieved in parallel plate reactors. The reactor duty is enhanced when it is operated under limiting current conditions at the cathode. Such conditions are closely related to the fluid pattern over the entire cathode area. In this work, the theoretical feasibility for the removal of Cu2+ ions in an electrochemical reactor at laboratory level was analyzed as a function of the flow pattern. A commercial computational fluid dynamics code (ANSYS Fluent) was used to describe the hydrodynamic as the electrolyte passes through a laboratory electrochemical reactor (channel reactor: 0.10 m length, 0.05 m width, 0.01 m depth and electrode area 0.005 m(2)). The simulation was performed at mean linear inlet flow velocities between 0.011 and 0.056 m s(-1). The flow predictions show how the development of the flow pattern is affected by both the manifold and the flow velocity. It was possible to estimate that the fluid flow was developed over the 90, 80 and 70% of the cathode area when the mean linear inlet flow were 0.011, 0.033 and 0.056 m s(-1), respectively. Under these hydrodynamic conditions, the electrochemical reactor performance will be maximized because it was expected to have a uniform limiting current density over the cathode area according to the estimated percentages mentioned before. In the same range of linear flow velocities, a uniform limiting current for cathodic Cu2+ reduction was experimentally obtained, as expected.