The study of membrane capacitive deionization from charge efficiency

Abstract

A B S T R AC TMembrane capacitive deionization (MCDI) is a promising technology for desalination with the potential of lowering energy consumption and treatment cost. In this paper, batch mode experiments were carried out to evaluate the charge effi ciency of the MCDI process. Specifi cally, charge effi ciency is a very functional tool to examine the double layer structure inside of porous electrode. The results show that the charge effi ciency in MCDI is a function of both cell voltage and solution conductivity. Specifi cally, it was found that the charge effi ciency was proportional to cell voltage while inversely to solution conductivity. The maximum charge effi ciency (0.55) in MCDI was far less than one, indicating the high transient resistivity between membrane and carbon electrodes.

Synthesis of Three-Dimensional Graphene-Based Hybrid Materials for Water Purification: A Review

“…The desalination performance of the proposed 3D GO-PVA composites in a MCDI configuration was evaluated through specific salt adsorption, salt adsorption capability and charge efficiency, respectively. A salt adsorption capability as high as 36.1 mg/g in 750 mg/L salt solution was obtained with 1.2 V applied voltage (Figure 9d,e) and the corresponding charge efficiencies (Figure 9f) reported by Leong and co-workers are higher than that of conventional CDI [226] and MCDI using porous carbons [227].…”

Recent Progresses in Adsorption Mechanism, Architectures, Electrode Materials and Applications for Advanced Electrosorption System: A Review

“…To our knowledge, the ion removal efficiency of CDI technology can be improved by optimizing the device configuration and performances of electrode materials. The traditional CDI system ( Figure 2 a) has some inherent obstacles, including co-ion effect interference, intermittent operation of adsorption and desorption, and oxidation of electrode materials [ 31 , 32 , 33 ]. To overcome the shortcomings, new CDI cell architectures have been developed such as membrane capacitance deionization technology (MCDI), flow electrode capacitance deionization technology (FCDI), and hybrid capacitance deionization technology (HCDI), which can introduce novel features into this field.…”

Current to Clean Water – Electrochemical Solutions for Groundwater, Water, and Wastewater Treatment

“…Since electrosorption is a purely capacitive process and faradaic processes, such as degradation of the electrode or electrolysis of water, play a subordinate role, the current efficiency (CE) is usually quite high (between 0.5 and 0.8). Furthermore, CDI devices have a long service life and low maintenance is required , . Moreover, because of the pure capacitive process, there is no electron transfer between the electrode (cathode) and the metal‐ion.…”