Optimization of Capacitive Deionization for Salt Removal from Water with Response Surface Methodology

A efficient treatment method capacitive deionization (also called electrosorption) against high salinity and ionic concentration in wastewater or groundwater was discussed. Response surface methodology was used to investigate the effect of electrodes potentials, distance between electrodes plates and flow rates on the desalination rate from water. A quadratic response surface model and optimum level values were obtained based on experimental data under box-behnken design (BBD) of software Design-Expert 8.0. The results showed that the maximum desalination rate was 59.05% on the optimal conditions of potentials, distance between electrodes plates and flow rates were 1.6 V, 2 mm, and 21.32 ml/min, respectively. The analysis of variance on quadratic response surface model indicated that regression model reached significant level, fit well and its reliability and accuracy were in the practicable extent, coinciding with the experimental results perfectly.