Enhanced desalination efficiency of flow-through capacitive deionization cell by mesh electrode with granular aerogel carbon in the removal of ions from synthetic and real samples

Abstract

Flow-through capacitive deionization (FTCDI) is a traditional improved flow-by CDI cellular structure, used to remove ions from aqueous solutions. In this study, a new FTCDI was designed consisting of mesh electrodes (ME) containing ion-exchange membranes (IEM) and aerogel carbon granules with a specific surface area of 489 m2/g. All analyses and experiments performed showed that the new design can remove nitrate, phosphate, sodium, calcium, and chloride. Under optimal conditions, the new FTCDI system can remove 82.5, 49, 85, and 90% of sodium chloride, calcium chloride, nitrate, and phosphate with a maximum input concentration of 450 mg/L, 450 mg/L, 70 mg/L, and 3 mg/L, respectively. The efficiency of this system was also evaluated for real samples. Findings of the study showed that if the initial amount of turbidity is 12 NTU, total soluble solids (TDS) 1,700 mg/L, total hardness 540 mg/L, phosphate 0.09 mg/L, nitrate 28.8 mg/L, and electrical conductivity (EC) 3,480 μs/cm, the system can remove 25, 23.5, 33.3, 66.6, 54.4, and 39.1%, respectively.

Composite modification of carbon fiber cathode with tree-like branched polypyrrole-microwires and polyaniline-nanorods for enhancing hexavalent chromium reduction

“…In addition, the higher electrode potentials could theoretically enhance the electrostatic attraction between the Cr species and electrodes for increasing the Cr tot removal. 37,38 However, the ERD showed lower Cr tot removal under higher voltages, which was because stronger redox reactions (currents in Fig. 6c) on the electrodes inhibited the Cr species adsorption.…”