Acid treated RHWBAC electrode performance for Cr(VI) removal by capacitive deionization and CFD analysis study

In this work acid-treated activated carbon was developed from rice husk, and it was used as raw material for Capacitive deionization (CDI) electrodes. The prepared acid treated rice husk waste biomass activated carbon (RHWBAC) electrode was used for the electrosorption of Cr(VI) from the aqueous medium. This RHWBAC electrode shows maximum electrosorption capacity was 2.8316 mg g−1 of initial feed concentration 100 mg L−1 at 1.2 V. The result shows that the electrosorption method follows Redlich Peterson isotherm, Langmuir isotherm model, and Pseudo first order kinetic model. The computational fluid dynamics (CFD) analysis of square CDI cell design shows that the stagnant regions decreases by increasing the flow rate of feed. The present work concluded that the RHWBAC could be capable electrode material for Cr(VI) sorption from low concentrated aqueous feed. [Display omitted] •Electrode preparation from rice husk waste biomass activated carbon.•RHWBAC electrodes were used for removal of Cr(VI) by Capacitive Deionization.•Best suitable isotherm model are Langmuir and Redlich Peterson isotherm model.•Pseudo first order model shows better fit with experimental results.•The study investigates the presence of stagnant regions through CFD analysis.