Performance comparison of lithium fractionation from magnesium via continuous selective nanofiltration/electrodialysis  

作　　者：Yong Xu Qingbai Chen Yang Gao Jianyou Wang Huiqing Fan Fei Zhao 

机构地区：[1]Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution,College of Environmental Science and Engineering,Nankai University,Tianjin 300350,China [2]College of Chemical Engineering and Material,Quanzhou Normal University,Quanzhou 362000,China [3]Center for Water and Ecology,State Key Joint Laboratory of Environment Simulation and Pollution Control,School of Environment,Tsinghua University,Beijing 100084,China

出　　处：《Chinese Journal of Chemical Engineering》2023年第7期42-50,共9页中国化学工程学报（英文版）

基　　金：financial support by the National Key Research and Development Program of China(2017YFC0404003);the Tianjin Natural Science Foundation(21JCZDJC00270);the China Postdoctoral Science Foundation(2021M701875);the Tianjin Special Project of Ecological Environment Management Science and Technology(18ZXSZSF00050);the Tianjin Science and Technology Support Project(19YFZCSF00760);the Fundamental Research Funds for the Central Universities(63221312).

摘　　要：Although selective nanofiltration(SNF)and selective electrodialysis(SED)have been widely adopted in the field of Mg^(2+)/Li^(+)separation,their differences have not been illustrated systematically.In this study,for the first time,SNF and SED processes in continuous mode were studied for Li+fractionation from the same brine with high Mg/Li ratios and their differences were discussed in detail.For a fair analysis of the two processes,typical factors were optimized.Specifically,the optimal operating pressure and feed flow rate for SNF were 2.4 MPa and 140 L·h^(-1),respectively,while the optimal cell-pair voltage and replenishment flow rate for SED were 1.0 V and 14 L·h^(-1),respectively.Although the Li^(+)fractionation capacity of the two processes were similar,the selectivity coefficient of SNF was 24.7% higher than that of SED and,thus,the Mg/Li ratio in purified stream of the former was 19.0% lower than that of the latter.Due to higher ion driving force,SED had clear advantages in recovery ratio and concentration effects.Meanwhile,the specific energy consumption of SED was 20.1% lower than that of SNF.This study provided a better understanding and guidance for the application and improvement of the two technologies.

关 键 词：High Mg/Li brine PURIFICATION Membrane NANOFILTRATION ELECTRODIALYSIS Lithium recovery 

分 类 号：TS396.5[轻工技术与工程]