废旧锂离子电池热处理过程中污染物的迁移转化  

Migration and Transformation of Pollutants During the Thermal Treatment of Spent Lithium-Ion Batteries

作　　者：周杰 王景伟[1] 马恩[1] ZHOU Jie;WANG Jingwei;MA En(School of Resources and Environmental Engineering,Shanghai Polytechnic University,Shanghai 201209,China)

机构地区：[1]上海第二工业大学资源与环境工程学院,上海201209

出　　处：《上海第二工业大学学报》2023年第2期111-118,共8页Journal of Shanghai Polytechnic University

基　　金：国家重点研发计划“固废资源化”重点专项(2019YFC1904400)资助。

摘　　要：电动汽车产业的发展带来锂离子电池需求大增,将会产生大量的废旧锂离子电池,回收废旧锂离子电池可以节约大量资源。热处理是锂离子电池回收工艺中的重要环节,但锂离子电池中的电解液、有机黏结剂和金属成分极易在加热过程中挥发从而污染环境,所以分析热处理过程中产生的污染物具有重要意义。以废旧三元锂离子电池为原材料,分别在100、200、300、400、500、600℃和惰性气氛条件下加热,保温时间60 min,氮气流量500 mL/min,升温速率10℃/min。采用TG-MS、XRD、SEM、ICP-AES、GC-MS等表征和分析产物。结果表明,金属挥发率随着温度的升高而增加,但是总体挥发率不超过1%;电解液会发生分解和挥发行为,分解产物主要是CO_(2)、H_(2)O和小分子烷烃;LiPF_(6)分解产生氟化物,PVDF和隔膜的分解产生有机污染物;挥发的氟化物随着温度的升高而增加,产生的有机气体可以作为原料进行回收,且热解后的材料更有利于回收。The development of the electric vehicle industry has brought a great increase in the demand for lithium-ion batteries,and a large number of s spent lithium-ion batteries will be produced in the future.Recycling waste lithium-ion batteries can save a lot of resources.Heat treatment is an important step in the recovery process of lithium battery,but the electrolyte,organic binder and metal components of lithium battery are easy to volatilize in the process of heating and pollute the environment.It is of great significance to analyze the pollutants produced during heat treatment.In this study,waste ternary lithium-ion batteries were used as raw materials and heated at 100,200,300,400,500,600℃and inert atmosphere,respectively.The holding time was 60 min,the nitrogen flow rate was 500 mL/min,and the heating rate was 10℃/min.The product was characterized and analyzed by TG-MS,XRD,SEM,ICP-AES,GC-MS,etc.The results show that the volatilization rate of metal increases with the increase of temperature,but the total volatilization rate does not exceed 1%.The decomposition and volatilization of electrolyte occur,and the decomposition products are mainly CO_(2),H_(2)O and small molecule alkanes.The decomposition of LiPF_(6) produces fluorine-containing compounds,and the decomposition of PVDF and separator produce organic pollution.The volatile fluorine-containing compounds increase with the increase of temperature,and the generated organic gas can be used as raw material for recovery,and the pyrolyzed material is more conducive to recovery.

关 键 词：废旧锂离子电池 热解 金属 氟化物 有机物 

分 类 号：X502[环境科学与工程—环境工程]