Application of stacked carbon fiber electrodes in desalination of membrane capacitive deionization

Abstract

In order to improve the total adsorption capacity and desalination performance of the electrode in electrochemical desalination device, the stacked carbon fibers were used as the electrode, and titanium mesh was added between the electrodes to enhance the conductivity between the electrode layers. The control variaties was used to design desalination experiments to investigate the effects of inlet salt concentration, stacked carbon fiber electrode thickness and increased titanium mesh conductor on desalination performanceThe adsorption process was analyzed from the perspective of adsorption thermodynamics and kinetics. The experimental results show that stacking carbon fiber electrodes could lead to a decrease in desalination efficiency, the adsorption capacity of each layer decreases from 974 mg/g to 286 mg/g. But adding multiple layers of titanium mesh as a conductive material can effectively improve the desalination rate. When the spacing increases by three layers of titanium mesh, the adsorption speed increases by 21 times compared to the first layer. Stacking carbon fiber electrodes can solve the problem of limited adsorption capacity of single-layer electrodes and inability of handling high concentration saline water for a long time. Adding titanium mesh can effectively improve the conductivity of multi-layer electrodes, thereby improving desalination performance. It provides new ideas for the design of multi-layer electrodes and the improvement of electrode conductivity, and has guiding significance for the engineering application of capacitive deionization.

Keywords

• other disciplines of environmental engineering; stack electrode; membrane capacitance deionization; activated carbon fiber; titanium mesh; desalination performance