Kinetic and isotherm studies on the electrosorption of NaCl from aqueous solutions by activated carbon electrodes

The electrosorption performance of activated carbon (AC) electrodes with various potentials and concentrations was studied. It was found that electrosorption capacity and rate increased with the increasing of the bias potentials and solution concentrations. Such trend was found to be correlated to the increase of the electrostatic force and the decrease of the electrolyte resistance. The investigation of the electrosorption isotherm showed that the experimental data can be well represented by Langmuir isotherm. And the kinetics analysis indicated that the electrosorption of NaCl onto AC electrodes followed pseudo-first-order kinetics model.

Research highlights► Electrosorption capacity and rate of NaCl increased with the increasing of the bias potentials and solution concentrations. ► Electrosorption capacity and rate are correlated to the increase of the electrostatic force and the decrease of the electrolyte resistance. ► Electrosorption isotherm of NaCl onto AC electrodes followed Langmuir isotherm. ► Kinetics analysis indicated that the electrosorption of NaCl onto AC electrodes followed pseudo-first-order kinetics model.