Electrochemical properties of MCDI-utilized PVA/SSA/GA cation exchange membrane

Abstract

     Membrane capacitive deionization (MCDI), an alternative desalination technology that uses a voltage between two electrodes that are covered with ion-exchange membranes to remove salt, has been drawing a lot of research attention. It has been demonstrated that the desalination performance in terms of salt removal and energy efficiency can be maximized when ion-exchange materials are incorporated on the electrodes in MCDI. In this study, the electrochemical properties of the MCDI electrodes coated with PVA/SSA/GA cation exchange membrane were intensively investigated, specifically the effect of sulfosuccinic acid (SSA) and glutaric anhydride (GA) content in the cross-linking reaction with polyvinyl alcohol (PVA). The presence of SSA in the cation exchange membrane helps improve its conductivity, as proven by the electrochemical measurements via cyclic voltammetry and galvanostatic charge-discharge. As a result, the salt adsorption capacity was also enhanced in the addition of SSA and GA into the PVA chain. The PVA/SSA/GA cation exchange membrane is proved to be an inexpensive, environmentally friendly and suitable candidate to be utilized in the MCDI systems.