Review of the current state of technology for capacitive deionization of aqueous salt solutions

Abstract

The availability of clean water at affordable prices is one of the key technological, social, and economic challenges of the 21st century. The increased extraction of groundwater worldwide is leading to the gradual intrusion of salty water into sources and water horizons. In order to use this water for industrial and agricultural purposes, or as drinking water, it needs to be purified and desalinated. Thus, methods of desalinating water of different salinity levels, ranging from brackish to seawater, are becoming more prominent. The overall goal of current research is to make water desalination technologies more energyefficient and cost-effective. One promising technology that meets these requirements is capacitive deionization (CDI) of water. This technology has been widely known for over 30 years, but significant progress in CDI research has only been achieved in recent years. In this review, we examine the currently developed architectures of CDI cells, advancements in carbon materials, and discuss the prospects and challenges of commercializing this technology.