A study of the capacitive deionisation performance under various operational conditions

► Ion selectivity of CDI depends mainly upon the charge and hydrated radius of ions. ► CDI efficiencies increase by decreasing feed temperature, TDS and flow rate. ► Energy consumption of CDI is inversely proportional with the flow rate. ► Energy consumption of CDI is directly proportional with the TDS feed concentration. ► Silica did not cause deterioration of CDI under various operational conditions.