Bio-inspired fabrication of Ester-functionalized imprinted composite membrane for rapid and high-efficient recovery of lithium ion from seawater

Chao Yu; Jian Lu; Jingwen Dai; Zeqing Dong; Xinyu Lin; Wendong Xing; Yilin Wu; Zhongfei Ma

doi:10.1016/j.jcis.2020.03.091

Bio-inspired fabrication of Ester-functionalized imprinted composite membrane for rapid and high-efficient recovery of lithium ion from seawater

J Colloid Interface Sci. 2020 Jul 15:572:340-353. doi: 10.1016/j.jcis.2020.03.091. Epub 2020 Mar 30.

Authors

Chao Yu¹, Jian Lu², Jingwen Dai³, Zeqing Dong², Xinyu Lin², Wendong Xing², Yilin Wu⁴, Zhongfei Ma⁵

Affiliations

¹ School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China; Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
² Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
³ China Aviation Lithium Battery Research Institute Co. Ltd., Changzhou 213200, China; Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
⁴ Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China. Electronic address: wuyilin@ujs.edu.cn.
⁵ School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China. Electronic address: mzf@ujs.edu.cn.

PMID: 32272311
DOI: 10.1016/j.jcis.2020.03.091

Abstract

Lithium ion (Li⁺) is one of the important sustainable resource and it's urgently demanded to develop high-selectivity and high-efficient method to extract of Li⁺ from seawater. Hence, we propose the ester-functionalized ion-imprinted membrane (IIMs) with high selectivity and stability for the rebinding and separation of Li⁺ in aqueous medium via ion imprinted technology and membrane separation technology. In this work, the hydrophilic polydimethylsiloxane membranes (PDMS) are synthesized by self-polymerization of dopamine (DA) in aqueous solution, resulting in the fabrication of dense poly-dopamine (PDA) layer on the surface of PDMS (PDMS-PDA). In view of weak bonding forces (such as hydrogen bond, ionic bond and Van der Waals' force) between traditional imprinted polymer and ligand, the ester groups are formed between modified PDMS-PDA and ligand by surface grafting. The obtained Li⁺ imprinted membranes (Li-IIMs) have a suitable cavity and high adsorption capacity toward Li⁺ which reveal a high rebinding capacity (50.872 mg g^-1) toward Li⁺ based on ample rebinding sites and strong affinity force. The superior relative selectivity coefficients (α_Na/Li, α_K/Li and α_Rb/Li are 1.71, 4.56 and 3.80, respectively) can be also achieved. The selectivity factors of Li-IIMs for Na⁺, K⁺ and Rb⁺ are estimated to be 2.52, 2.8 and 3.03 times larger than Li⁺ non-imprinted membranes (Li-NIMs), which imply the superior selectivity of Li-IIMs toward Li⁺. The regeneration ability of Li-IIMs is observed by systematic batch experiments. In summary, it can be concluded that the rebinding capacities of Li-IIMs is slightly decrease after eluting process, owing to the Li-IIMs with outstanding stability performance. Presentation of the method pave a fine prospect for coming true the long-term use of imprinted membrane.

Keywords: Ester groups; Ion-imprinted membrane (IIMs); Lithium ion (Li(+)); PDMS-PDA; Regeneration ability.