Recovery of Li_(2)CO_(3)and FePO_(4)from spent LiFePO_(4)by coupling technics of isomorphic substitution leaching and solvent extraction  

作　　者：Yong Niu Xiaowu Peng Jinfeng Li Yuze Zhang Fugen Song Dong Shi Lijuan Li 

机构地区：[1]Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources,Engineering Laboratory for Green Applications of Salt Lakes and Salt Deposits,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining 810008,China [2]Qinghai Technology Research and Development Center of Comprehensive Utilization of Salt Lakes Resources,Xining 810008,China [3]Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032,China [4]University of Chinese Academy of Sciences,Beijing 100049,China [5]Innovation Academy for Green Manufacture,Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Chinese Journal of Chemical Engineering》2023年第2期306-315,共10页中国化学工程学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(U1707601);project of Youth Innovation Promotion Association,Chinese Academy of Sciences(2021430);project of Innovation Academy for Green Manufacture,Chinese Academy of Sciences(IAGM2020C26);project of Bureau of International Cooperation,Chinese Academy of Sciences(122363KYSB20190033)。

摘　　要：Efficient and low-cost recycling of spent lithium iron phosphate(LiFePO_(4),LFP)batteries has become an inevitable trend.In this study,an integrated closed-loop recycling strategy including isomorphic substitution leaching and solvent extraction process for spent LFP was proposed.An inexpensive FeCl_(3)was used as leaching agent to directly substitute Fe^(2+)from LFP.99%of Li can be rapidly leached in just 30 min,accompanied by 98%of FePO_(4)precipitated in lixivium.The tri-n-butyl phosphate(TBP)-sulfonated kerosene(SK)system was applied to extract Li from lixivium through a twelve-stage countercurrent process containing synchronous extraction and stepwise stripping of Li^(+)and Fe^(3+).80.81%of Li can be selectively enriched in stripping liquor containing 3.059 mol·L^(-1)of Li^(+)under optimal conditions.And the Fe stripping liquor was recovered for LFP re-leaching,of which,Fe^(2+)was oxidized to Fe^(3+)by appropriate H_(2)O_(2).Raffinate and lixivium were concentrated and entered into extraction process to accomplished closeloop recycling process.Overall,the results suggest that more than 99%of Li was recovered.FeCl_(3)holding in solution was directly regenerated without any pollutant emission.The sustainable mothed would be an alternative candidate for total element recycling of spent LFP batteries with industrial potential.

关 键 词：Spent LiFePO_(4) Leaching lithium Extraction STRIPPING RECOVERY 

分 类 号：X705[环境科学与工程—环境工程] TQ131.11[化学工程—无机化工] TQ138.11