Synergistic leaching process of waste LiFePO4 with phosphoric acid-tartaric acid system
Recycling valuable metals from waste LiFePO4 power batteries and realizing their resource utilization is an urgent problem at present.In this study,a mixed leaching system of phosphoric acid and tartaric acid was proposed,and the total component leaching recovery process of waste LiFePO4 was studied.The approximate range of leaching conditions was obtained through the results of single factor experiments,and then the response surface method was used to optimize different leaching conditions to obtain the best leaching process.The results showed that the leaching rates of Li and Fe were 97.55％and 98.67％respectively when the concentration of phosphoric acid was 3.1 mol/L,the concentration of tartaric acid was 1.3 mol/L,the liquid-solid ratio was 6.8∶1,the stirring speed was 500 r/min and the reaction temperature was 65℃ for 5 h.The experimental results show that tartaric acid can be replaced with the Fe3+released by phosphate,and the synergy of mixed acids will immerse all Li and Fe in the waste into the solution.By adjusting the molar ratio of Li∶Fe∶P in the leaching solution,the regenerated LiFePO4(RE-LiFePO4)was synthesized by spray drying-sintering method.In the whole recovery process,there is almost no waste acid and waste gas emission,and the green recovery of all components of waste LiFePO4 is realized.
waste LiFePO4 batteryrecyclemixed leachingresponse surface methodspray drying process
万方数据
维普
