文献类型：期刊文献

英文题名：Insights into the thermodynamics of selective lithium extraction with lithium iron phosphate from high salinity system

作者：Zhou, Shiyu[1];Wang, Penglin[1];Wang, Yihao[3];He, Jiajun[3];Zhang, Yu[3];Xia, Xinni[3];Gu, Shuai[1,2];Yu, Jianguo[1,2]

机构：[1]East China Univ Sci & Technol, Natl Engn Res Ctr Integrated Utilizat Salt Lake, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Joint Int Lab Potassium & Lithium Strateg Resource, Shanghai 200237, Peoples R China;[3]East China Univ Sci & Technol, Sch Chem Engn, Shanghai 200237, Peoples R China

年份：2025

卷号：354

外文期刊名：SEPARATION AND PURIFICATION TECHNOLOGY

收录：;EI(收录号：20243016755265);WOS:【SCI-EXPANDED(收录号:WOS:001279395600001)】；

基金：This work was supported by the Shanghai Sailing Program (grant number 21YF1409000) , the Nature Science Foundation of Shanghai (grant number 22ZR1415800) , and the National Natural Science Foun-dation of China (grant number 52304422) .

语种：英文

外文关键词：LiFePO 4 /FePO 4 redox couple; Thermodynamic corrections; Electroredox-enabled lithiation/delithiation; Dissolution mechanism; Lithium selective extraction

摘要：With the escalating lithium demand, selective lithium extraction from salt-lake brines with electroredox enabled lithiation/delithiation couples, e.g., LiFePO4 (LFP)/FePO4 (FP), has attracted extensive attention. However, the dissolution behavior obtained from the Eh-pH diagram, the primary tool available for studying the dissolution behavior of the LFP/FP redox couple (LFP/FP-RC), demonstrates a notable discrepancy with experiment results in the high salinity (HS) system. Here, the activity coefficient and ionic strength amendments are introduced into the thermodynamic calculation matrix to predict the species distributions of the LFP/FP-RC and reveal the dissolution mechanism in the HS system. Excellent agreement between thermodynamic calculations and experimental results is achieved with the simplified Helgeson-Krikham-Flowers (HKF) model verifying the feasibility of the proposed thermodynamic calculations. Thermodynamic calculations revealed that the dissolution behavior discrepancy between LFP and FP is induced by their solubility products and the formation of more thermodynamically stable species, and the optimum pH range for the utilization of the LFP/FP-RC in the HS system is clarified for the first time. At the optimum pH, the LFP/FP-RC capacity can achieve 38 mg/g with extremely low average dissolution ratios, which could reduce the global warming potential by one-third.