1. Facile surface modification of cation exchange membranes via Debus-Radziszewski in-situ cross-linking for lithium extraction from salt-lakes.
- Author
-
Xie, Xiang-Yun, Huo, Hui-Qian, Zhang, Wen-Hao, Zhao, Yan, Ji, Yan-Li, Van der Bruggen, Bart, and Gao, Cong-Jie
- Subjects
- *
LITHIUM , *POLYETHYLENEIMINE , *ELECTRODIALYSIS , *CATIONS , *ENERGY consumption , *IMIDAZOLES - Abstract
[Display omitted] • The PEI-Im-CTG CEMs were modified via Debus-Radziszewski in-situ crosslinking. • The PEI-Im layer had rigid structure and strong cation-surface interaction. • The PEI-Im-CTG membrane exhibited high permselectivity between Li+ and Mg2+. • The PEI-Im-CTG membrane showed a high Li+ purity during two-stage ED process. Lithium extraction from salt-lakes is a crucial way to solve the global shortage of lithium resources. With high sustainability and efficient ion separation, electrodialysis (ED) has a high potential for lithium extraction from salt-lakes, yet suffering from the challenges of cation-cation selectivity. In this work, a facile Debus-Radziszewski in-situ cross-linking approach was proposed to construct a polyethyleneimine modification layer containing imidazole groups (PEI-Im) on a common cation exchange membrane (commercial membrane, i.e., CTG membrane) surface to enhance the lithium selectivity. The pore size, architecture rigidity and charged characteristic of this PEI-Im layer were controlled via adjusting the reaction conditions. The resultant membrane (PEI-Im-CTG) exhibited high Li+ permeation rate (0.89 mol·m−2·h−1) and excellent Li+/Mg2+ permselectivity (13.1), which are 4.0 times and 19.8 times higher than that of the pristine CTG membrane, respectively. Moreover, the PEI-Im-CTG membrane based two-stage ED process showed a high Li+ purity (∼99.90 %) and low energy consumption (∼0.158 kWh·mol-1Li+) for Li+ extraction from simulated salt-lakes. This work offers a facile and effective strategy for membrane modification with high Li+ selectivity, which is promising in lithium extraction from salt-lakes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF