닫기

Create wq

Lab. on Chemical Redox Acceleration Technologies for Water Quality

home    Publication    Journal

Journal

Bifunctional Deionization and Lithium Recovery Via Four-Step Constant Voltage Operation of Hybrid Capacitive Deionization with Composite Electrodes
Year of publication 2023
Title of paper Bifunctional Deionization and Lithium Recovery Via Four-Step Constant Voltage Operation of Hybrid Capacitive Deionization with Composite Electrodes
Author Sung-il Jeon, Sungho Bae, Kangwoo Cho*
Publication in journal 244th ECS Meeting
Status of publication accepted
Vol
Link https://ecs.confex.com/ecs/244/meetingapp.cgi/Paper/178265 237회 연결

The efficient recovery of valuable resources from wastewater has become a crucial challenge in the era of a carbon-neutral society. Capacitive deionization (CDI) has been employed in electrochemical lithium recovery (ELR) processes, based on selective Li+ intercalation to LiMn2O4 (LMO). In this study, we propose a four-step constant voltage operation (forward/zero/reverse/zero) of bifunctional hybrid CDI to produce deionized water as well as Li+-rich concentrate within a cycle. This unique performance was enabled by composite electrodes with capacitive activated carbon cloth (ACC) impregnated with redox-active LMO and Ag, respectively, which were characterized and evaluated through material characterization and electroanalysis. The proposed CDI system demonstrated deionization (step 1; forward voltage) and selective Li+ enrichment (step 3; reverse voltage) without influent replacement. The performance of the CDI system was evaluated through single pass experiments with binary NaCl and LiCl solutions (10 mM each) under 1.0/0/-1.0/0 V operation, revealing supreme performance with mass loadings of 32.6 mg/cm2 for LMO and 3.3 mg/cm2 for Ag. Furthermore, the long-term stability of the system was confirmed, indicating its potential for practical implementation. The proposed bifunctional CDI system, combining ELR with water treatment, paves the way for advancing resource recycling from wastewater.