A sustainable approach for recovering battery grade FePO4 and Li2CO3 from Al/F-bearing spent LiFePO4/C powder was proposed, including acid leaching, fluorinated coordination precipitation, homogeneous precipitation, and high-temperature precipitation. Under the optimal conditions, the leaching efficiencies of Li, Fe, P, Al, and F were 97.6%, 97.1%, 97.1%, 72.5%, and 63.3%, respectively. The effects of different parameters on the removal of Al/F impurities were systematically evaluated, indicating about 99.4% Al and 96.4% F in the leachate were precipitated in the form of Na3Li3Al2F12, and their residual concentrations were only 0.0124 and 0.328 g/L, respectively, which could be directly used to prepare battery grade FePO4 (99.68% in purity). Lithium in the Al/F-bearing residue could be extracted through CaCO3-CaSO4 roasting followed by acid leaching, ultimately obtaining 99.87% purity of Li2CO3. The recovery rates of Li and Fe were 96.88% and 92.85%, respectively. An economic evaluation demonstrated that the process was profitable.
吴业惠子,周康根,彭长宏,易 葵,邓景焜,邱在容,陈 伟,张可菁
. Regeneration of battery grade FePO4 and Li2CO3 from Al/F-bearing spent LiFePO4/C powder[J]. Transactions of Nonferrous Metals Society of China, 2024
, 34(10)
: 3520
-3532
.
DOI: 10.1016/S1003-6326(25)66897-X