ENHANCING COPPER REMOVAL THROUGH INTEGRATED CAPACITIVE DEIONIZATION WITH HETEROGENEOUS CATION EXCHANGE MEMBRANE

Abstract

Capacitive deionization (CDI) is a novel technique to eliminate ions present in the solution. This study was designed to evaluate the impact of cation exchange resin loading on the membrane using the nonsolvent-induced phase inversion method. After optimizing the resin loading on the membrane, the prepared membrane was employed for the membrane capacitive deionization (MCDI). A concentration of 500 mg.L-1 Cu2+ was used as a test contaminant in the CDI system to study Cu2+ removal and recovery at different voltages. Results showed that resin loading substantially influenced the membrane structure and enhanced the Cu2+ removal by the CDI technique. The presence of cation exchange resin on the membrane was found by the appearance of a peak at 1,007 cm-1, 1,035 cm-1, and 1,128 cm-1 in the FTIR spectra of the –SO3 group, which became more significant as the amount of resin increased. The prepared membrane’s water uptake and ion exchange capacity increased as the quantity of resins loaded onto the membrane increased. When monitoring a current-time graph during CDI tests, an adsorption amount of 6.9 mg.g-1 of Cu2+ and recovery efficiency of 51.7 % at the 10th cycle in the MCDI cell was observed for M20 (20% by wt resin). Using the prepared membrane in the CDI system has the potential to remove Cu2+ from the solution selectively.