Determination du courant limite d'electrodialyse par conductivite pour les faibles nombres de reynolds. Cas des solutions de tartrate acide de potassium

In the case of an electrodialysis operation, it is possible to obtain the limiting current by measuring the conductivity of the solution undergoing dilution. Starting from the equation of the constant flux of matter, when the concentration at the membrane falls to zero, (i/σ_d)_crit = δ relates the current density i and the conductivity of the diluate σ_d. The critical value of (i/σ_d) is easily obtained from the drawing of σ _dvs the potential applied to the apparatus. Experiments carried on aqueous solutions of KHC₄H₄O₆ at 8 g/l show that (i/σ_d)_crit) is well related to the Reynold's number by the relation αRe^β. It is then possible to calculate the thickness δ of the diffusion layer as a function of the Reynold's number.