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The SEArcularMINE project aims to recover critical raw materials (CRMs) from brines from saltworks, thus facing a CRM shortage within Europe. To promote a fully circular scheme, the project valorises concentrated brines using electrodialysis with bipolar membranes (EDBM) to generate the required amounts of reactants (i.e., acids and bases). Regarding the performances of new non-woven cloth ion-exchange membranes (Suez): (i) an ultra-thin non-woven polyester cloth and (ii) a thin polypropylene cloth acting as the support structures were assessed. Additionally, the anion layer includes a catalyst to promote the water dissociation reaction. The effect of current density (100, 200, and 300 A m−2) on the performance of two combinations of membranes in an inter-laboratory exercise using 2 M NaCl was evaluated. According to statistical analysis ANOVA, there was an agreement on the results obtained in both laboratories. NaOH/HCl solutions up to 0.8 M were generated working at 300 A m−2 using both combinations of membranes. Regarding the performance parameters, stack set-ups incorporating thin polypropylene membranes showed lower specific energy consumption (SEC) and higher specific productivity (SP) than ultra-thin polypropylene ones. Hence, for ultra-thin polypropylene membranes, SEC was reported to be between 2.18 and 1.69 kWh kg−1NaOH and SP between 974 and 314 kg m−2 y−1.

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This paper presents an analysis of the current density distribution in the zinc plating process, using a two-dimension approach. The simulation presents a model based on COMSOL Multi-physics software. The simulation neglected the effect of mass transfer and production of gaseous species, in order to simplify the resolution. Additionally, a validation from the simulation through a comparison with the experimental data at similar conditions was performed. The results presented a good agreement between the experimental and simulated data. The graphics from both approaches showed a decreasing trend in the current density along the cathode length. This trend arises from the electrons movement in the electrodes; electrons flow through the least resistive path. Given the fact that zinc electroplating incurs an important industrial application, simulation is becoming a promising way to optimization and improvement.