Effect of Chemically Treated / Untreated Carbon Cloth: Potential Use as Electrode Materials in the Capacitive Deionization Process of Desalination of Aqueous Salt Solution

Abstract

Capacitive deionization (CDI) process is a novel approach for desalination of an aqueous salt solution. In the present study, an activated carbon cloth (ACC) is proposed as effective electrode material. Initially the carbon cloth was activated in 1 M and 8 M HNO3 for 9 hours at room temperature. The untreated and chemically activated carbon cloth (ACC) electrode materials were subjected to BET surface area measurements in order to get information about their specific surface area, average pore size, total pore volume and micropore area. The above materials were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) also. The electrochemical studies for the electrodes were done using cyclic voltammetry (CV) in 0.1 M Na2SO4 medium. From the studies, it was found that resistivity of the activated carbon cloth electrodes (treated in 1 M and 8 M HNO3) was decreased significantly by the chemical oxidation in nitric acid at room temperature and its capacitance was found to be 90 F/g (1 M HNO3) and 154 F/g (8 M HNO3) respectively in 0.1 M Na2SO4 solution. The capacitive deionization behavior of a single cell CDI with activated carbon cloth electrodes was also studied and reported in this work. Keywords: Activated carbon cloth, capacitive deionization (CDI), desalination, chemical activation, cyclic voltammetry, chronocoulometry