New insight into the performance analysis of flow-electrode capacitive deionization by varying the operation voltage

Abstract

In the flow-electrode capacitive deionization (FCDI), the highly activated porous carbon electrodes of the slurry phase flow through the channels of current collectors and adsorb the salt ions when a voltage is applied. In this study, the effect of voltage on the performance of an FCDI cell is experimentally investigated. The voltage is applied to the top corner of an FCDI cell (Vapply) and simultaneously the voltage of the central cell (Vcell) is measured. The experiments were conducted by applying voltages from 0.6 to 3.9 V. The experimental results show that the difference between Vapply and Vcell is a function of salt concentrations of the feed water. The higher voltages (Vapply>1.2V) can be used for increasing the salt removal efficiency (E) for higher saltwater concentrations without electrolysis. Also, the results show that E increases along with the applied voltage. A series of pH measurements were done in regard to investigating of electrolysis point of the setup.

DOI: 10.24200/SCI.2020.53645.3347