IPE-23萃取剂在含锂废液中回收锂的应用  

Application of IPE-23 extractant in the recovery of lithium from lithium-containing waste liquors

作　　者：何方 许高洁 裴翔 孙德智[1] 宁朋歌[2] 曹宏斌 HE Fang;XU Gaojie;PEI Xiang;SUN Dezhi;NING Pengge;CAO Hongbin(College of Environmental Science&Engineering,Beijing Forestry University,Beijing 100083,China;Institute of Process Engineering,Chinese Academy of Sciences,Chemistry&Chemical Engineering Date Center,CAS,Beijing 100190,China)

机构地区：[1]北京林业大学环境科学与工程学院,北京100083 [2]中国科学院过程工程研究所,中国科学院化学化工科学数据中心,北京100190

出　　处：《化工进展》2024年第S01期627-639,共13页Chemical Industry and Engineering Progress

基　　金：中国科学院战略性先导科技专项(XDA0430105)。

摘　　要：从废旧锂电池回收废液中进一步提取锂资源兼具经济和环境效益,β-双酮类溶剂萃取体系因其良好的萃锂性能得到了广泛的关注,但目前β-双酮类萃取剂的种类较少导致在选择上有一定的局限性。本研究通过Gaussian 16、Multiwfn软件进行了萃取剂分子表面静电势和萃锂反应吉布斯自由能变的理论计算,结果表明—NO_(2)、—CF_(3)、—CN取代基通过改变β-二酮分子范德华表面的静电势极值来提升萃锂性能,在此理论基础上开发出β-二酮类选择性提锂萃取剂IPE-23;以锂萃取率、分离比、萃取分相、萃取剂在水相中的溶损(以水相中的化学需氧量COD计)等衡量指标,研究了萃取剂浓度、温度、相比、加碱量等因素的影响,经过三级逆流萃取-三级逆流洗涤-CO_(2)酸化反萃工艺处理,锂的萃取率达到97%,分配比D_(Li)=21.90,锂钠分离系数为423.85,萃余液pH为11.3,COD为675.2mg/L,反萃液中锂浓度达到6.66g/L。本研究有望为废旧锂电回收废液中锂资源的高效循环回用提供技术参考与理论支撑。The further extraction of lithium ions from waste lithium-ion battery recycling solutions offers both economic and environmental benefits.β-diketone solvent extraction systems have garnered extensive attention due to their excellent lithium extraction capabilities.However,the limited variety ofβ-diketone extractants currently available results in certain selection constraints.This study conducted theoretical calculations of the molecular surface electrostatic potential of the extractant and the Gibbs free energy change of the lithium extraction reaction using Gaussian 16 and Multiwfn software.The results indicate that substituents such as—NO_(2),—CF_(3),and—CN can enhance lithium extraction performance by altering the electrostatic potential extrema of theβ-diketone's van der Waals surface.Based on this theoretical foundation,a selective lithium extraction agent,IPE-23,was developed.The impact of operational factors such as extractant concentration,temperature,phase ratio,and base addition was investigated using lithium extraction efficiency,separation ratio,extraction phase separation,and the loss of extractant in the aqueous phase(measured by the chemical oxygen demand in the aqueous phase)as evaluation metrics.Through a process of three-stage countercurrent extraction,three-stage countercurrent washing,and CO_(2)acidification stripping,the lithium extraction rate reached 97%,with a distribution ratio DLi of 21.90 and a lithium-sodium separation factor of 423.85.The pH of the remaining liquid was 11.3,with a COD of 675.2mg/L,and the lithium concentration in the stripping solution reached 6.66g/L.This study provides technical reference and theoretical support for the efficient recycling and reuse of lithium resources from lithium-containing wastewater.

关 键 词：含锂废液 溶剂萃取 分离 回收 湿法提锂 

分 类 号：TF826.1[冶金工程—有色金属冶金]