Selective leaching of LiFePO4 by H2SO4 in the presence of NaClO3

Abstract

Herein, problems commonly observed for the wet leaching of waste LiFePO4 cathode materials, namely extensive Fe leaching and impurity removal, are mitigated through the use of NaClO3, and the effects of leaching parameters on Fe, P, Li, and Al leaching efficiencies are probed. As a result, optimal leaching conditions are determined as temperature = 90°C, H2SO4 concentration = 1 M, liquid-to-solid ratio = 5:1, leaching time = 1 h, stirring speed = 150 rpm, and NaClO3 dosage = 25 g per 100 g raw material, with the corresponding Fe, P, Li, and Al leaching efficiencies obtained as 0.21, 0.03, 97.23 and 11.87%, respectively.