Electrochemical model of electro-flotation

The relationship between the electrolysis voltage and the other variables (such as inter-electrode spacing, electric conductivity, current density, pH, bubble void fraction etc.) of an electro-flotation (EF) process using a Ti based anode is analyzed. The Nernst equation, Tafel equation, Fick’s model, and Ohm’s law are applied to determine the Nernst potential, activation overpotential, concentration overpotential and ohmic overpotential respectively. The simulation results are compared with experimental data of the present study as well as with data obtained from the literature. The good agreement of the comparison indicates that the models derived can be used to calculate the total electrolysis voltage required for an EF cell under different operating conditions. The effect of void fraction between electrodes on the electrolysis voltage of EF is experimentally investigated. The Bubble volumetric fraction between the electrodes was estimated to be 25%–35%, which significantly increases the cell resistance and hence overall cell potential.