Recovery of V(V) from complex vanadium solution using capacitive deionization (CDI) with resin/carbon composite electrode

• Published in: Chemosphere (Oxford) Vol. 208; pp. 14 - 20
• Main Authors: Bao, Shenxu, Duan, Jihua, Zhang, Yimin
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2018
• Subjects: adsorption; aluminum; aqueous solutions; Capacitive deionization; carbon; Composite electrode; composite materials; deionization; electrodes; ions; Recovery; resins; Selectivity; silicon; sodium hydroxide; sulfuric acid; Vanadium; Capacitive deionization; Selectivity; Recovery; Vanadium; Composite electrode
• ISSN: 0045-6535; 1879-1298; 1879-1298
• DOI: 10.1016/j.chemosphere.2018.05.149

The resin-activated carbon composite (RAC) electrodes were fabricated and applied in capacitive deionization for recovery of V(V) from complex vanadium solution. The adsorption capacity of the RAC electrode for V(V) is extremely low and the reduction of V(V) is significant in low pH solution, but the adsorbed V(V) on the electrode increases obviously and the reduction of V(V) gradually diminishes with the rise of pH. However, as the pH is increased to 10, the adsorbed V(V) on the RAC electrode declines. The higher applied potential is beneficial to the adsorption of V(V) and 1.0 V is appropriate for the adsorption. The impurities ions (Al, P and Si) are mainly adsorbed in the electric double layers on the RAC electrode and V(V) is dominantly adsorbed by the resins in the electrode. The adsorbed impurity ions can be easily removed by diluted H2SO4 and V(V) can be effectively eluted by 10% NaOH solution. The vanadium-bearing eluent can be recycled to recover and enrich vanadium from the complex solution. The performance of the RAC electrode keeps stable during the cyclic operation. This study may provide a promising and novel method for the recovery and separation of metals from aqueous solution. •A novel resin-carbon composite electrode was fabricated for CDI treatment.•The composite electrode presents high selectivity for V(V).•The adsorption mechanism of ions on the composite electrode was illuminated.•V(V) can be separated and enriched by CDI with the composite electrode.