Opportunities and challenges of capacitive deionization for uranium extraction from seawater

Abstract

Uranium is an indispensable resource for the nuclear industry, while land-based uranium mines are limited in content and unevenly distributed. Therefore, uranium extraction from seawater (UES) holds great potential for sustainable energy production. Capacitive deionization (CDI) technology, known for its low energy consumption, simple process, environmentally friendliness, and high adsorption efficiency, holds significant potential for UES. This paper reviews the development history, principles, classifications, and applications of CDI technology. In the section on development history, we provide a brief overview of the early development of CDI technology, emphasizing key milestones in its application to UES and recent optimization efforts. In the section on principle and categorization, we contextualize CDI technology within UES applications for a comprehensive introduction. Additionally, in the application section, we concentrate on current applications of CDI technology in UES. Furthermore, this paper elaborates on the current research status of CDI for UES and its advantages in terms of adsorptivity, selectivity, and economic benefits. In terms of adsorptivity, CDI technology demonstrates its efficiency in adsorbing uranium ions, achieved through meticulous optimization of electrode structure and material selection. With regard to selectivity, CDI technology selectively extracts uranium while mitigating interference from competing ions through adept modulation of electrode materials and operational parameters, thereby enhancing extraction efficiency. Economically, CDI technology stands out due to its hallmark features of low energy consumption and cost-effectiveness, facilitating high-efficiency uranium extraction and providing substantial economic advantages over alternative methods in the UES domain. Lastly, we discuss the challenge factors (competing ions, salinity, pH, and biofouling) of this technology in the uranium extraction process, aiming to explore the feasibility and economic benefits of UES by using the CDI technology and providing theoretical support for further optimization and promotion of CDI applications in UES. Additionally, we aim to address some of the current challenges of uranium extraction using CDI by incorporating materials informatics and providing an outlook on this matter. This paper provides practical insights into the development and industrial progress of CDI technology in UES, aiming to offer valuable references for the subsequent research on CDI seawater uranium extraction to contribute to the sustainable utilization of seawater resources.