选择性絮凝强化废旧磷酸铁锂电池电极材料浮选分离  

Flotation of Electrode Materials in Spent LiFePO_(4) Batteries Enhanced by Selective Flocculation

作　　者：赵梅 崔瑞[1] 李盼武 张明 ZHAO Mei;CUI Rui;LI Panwu;ZHANG Ming(School of Resources and Environmental Engineering,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Hubei Xingfa Chemical Group Co.,Ltd.,Yichang 443000,Hubei,China)

机构地区：[1]武汉科技大学资源与环境工程学院,湖北武汉430081 [2]湖北兴发化工集团股份有限公司,湖北宜昌443000

出　　处：《矿冶工程》2024年第4期126-131,135,共7页Mining and Metallurgical Engineering

基　　金：国家自然科学基金(51704215)。

摘　　要：针对废旧磷酸铁锂电池电极材料浮选过程中的夹带和夹杂导致分离效果不佳的问题,利用聚乙烯吡络烷酮(PVP)和聚丙烯酸(PAA)选择性絮凝强化废旧磷酸铁锂电池混合电极材料的浮选分离过程,并分析PVP和PAA与电极材料的作用机理。结果表明:先加入的PVP通过氢键作用选择性吸附在石墨表面从而抑制石墨自发的疏水性絮凝,同时通过位点阻断后加入的PAA在石墨表面的吸附,使PAA选择性絮凝LiFePO_(4);PVP和PAA的联合使用在有效分散石墨的同时使LiFePO_(4)正极材料表观粒径(D50)由15.01μm增至26.17μm,有效减少了LiFePO_(4)在混合电极浮选过程中的夹带损失,使LiFePO_(4)正极材料的浮选回收率由71.41%提升到83.59%。In the flotation process of electrode materials from spent LiFePO_(4)batteries,the occurrence of entrainment and entrapment usually leads to poor separation effect.Aiming at such problem,selective flocculation with polyvinylpiroxanone(PVP)and polyacrylic acid(PAA)was adopted to enhance the flotation effect in an experimental study,and the interaction mechanism between PVP and PAA and electrode materials was also analyzed.Results show that the firstly added PVP can be selectively adsorbed on the graphite surface by hydrogen bonding,thus inhibiting the spontaneous hydrophobic flocculation of graphite.Then,due to site-blocking effect,the subsequently-added PAA is inhibited to be adsorbed on the graphite surface,leading to selective flocculation of LiFePO_(4)by PAA.A combined usage of PVP and PAA can not only make graphite effectively dispersed,but also lead to apparent particle size(D50)of LiFePO_(4)cathode material increased from 15.01μm to 26.17μm.As a result,the loss of LiFePO_(4)due to entrainment in the flotation process of mixed electrode can be effectively reduced,thus the recovery rate of LiFePO_(4)cathode material by flotation process can be improved from 71.41%to 83.59%.

关 键 词：磷酸铁锂 废旧电池回收 正极材料 石墨 电极材料 选择性絮凝 浮选 

分 类 号：X705[环境科学与工程—环境工程]