Scale-up of rotating cylinder electrode electrochemical reactor for Cu(II) recovery: Experimental and simulation study in turbulence regimen

This paper describes a methodology for scaling-up a RCE bench scale reactor (0.350 L) to pilot scale reactor (RCE-PP, 10 L) by means of geometric correlations, dimensionless numbers, and computational simulation (Comsol Multiphysics 3.5a) in 2D for hydrodynamics and mass transport in turbulence regimen. The methodology proposed is validated by experimental data of Cu(II) recovery from a solution mimicking an effluent of electroplating industry (0.019 M CuSO4 and 1 M H2SO4). The experimental conditions of Taylor number (5.22 × 105 to 7.84 × 105) and limiting current (51.56–74.67 mA cm−2) used in the present work ensure a turbulent flow regime and electrochemical reaction controlled by mass transport, respectively. Under these experimental conditions, the hydrodynamic behavior was described using the Reynolds-averaged Navier–Stokes equations and the κ–ɛ turbulence model as well as the wall functions based on the universal distribution of velocities for the near-wall region. The diffusion-convection equation was solved using the Kays–Crawford model for turbulent Schmidt number (ScT) and mass transfer wall functions of Launder–Spalding type. The simulation results of the RCE bench scale in 2D, using the fitting parameter A reported by Rivero et al. [1], predict the experimental data (error <8%) of copper concentration decay in the RCE-PP up to 80% of galvanostatic copper recovery.