膜科学与技术

可用于镁锂分离的双荷电纳滤膜研制

作者：苗闪闪，史乐，宋姿萍，厍景国，陈小乐，武春瑞，吕晓龙

单位：省部共建分离膜与膜过程国家重点实验室，材料科学与工程学院，天津工业大学，天津300387

关键词：纳滤膜；氨乙基哌嗪；均苯三甲酰氯；镁锂分离

出版年,卷(期):页码： 2023,43(4):37-43

摘要：

近年来，随着新能源材料的快速发展，锂的需求量大幅上涨。为满足日益增长的锂需求，采用纳滤技术从盐湖提锂已成为一种趋势。通过调控纳滤膜表面电荷和孔径以提高Mg2+的截留率和Li+的渗透率，可显著提高Mg2+/Li+选择性。本文采用氨乙基哌嗪（AEP）为水相单体、均苯三甲酰氯（TMC）为有机相单体，通过调控水相单体浓度变化，控制分离层致密性和正反面电荷，制备了具有镁锂选择性的平板纳滤膜。研究结果表明：采用该单体制备的纳滤膜对MgCl2截留率为97.6 %，单盐镁锂分离因子为24.5，在混盐体系中（Mg2+/Li+质量比为20）镁锂分离因子SLi，Mg为44.8。

In recent years, with the rapid development of new energy materials, the demand for lithium has risen dramatically. To meet the increasing demand for lithium, it has become a trend to use nanofiltration technology to extract lithium from the salt lake. The Mg2+/Li+ selectivity can be significantly improved by modulating the surface charge and pore size of nanofiltration membrane to improve the rejection of Mg2+ and permeation of Li+. In this paper, we used N-aminoethyl piperazine (AEP) as aqueous monomer and trimesoyl chloride (TMC) as organic phase monomer to prepare flat plate nanofiltration membranes with Mg2+/Li+ selectivity by regulating the concentration change of the aqueous phase monomer and controlling the denseness of the separation layer and the charge of the top and flip sides. It was found that the nanofiltration prepared with this monomer had a high MgCl2 rejection to 97.6 % and high LiCl/MgCl2 separation factor to 24.5 in single salt solution. In addition, the prepared nanofiltration membranes had good separation selectivity (SLi, Mg = 44.8) in the mixed salt system (Mg2+/Li+ mass ratio of 20

苗闪闪（1997-），女，河南周口人，硕士研究生，研究方向为复合纳滤膜研制；电子邮件：1575061390@qq.com

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