The research reports a novel green method to use citrus fruits for the management of spent NMC based lithium ion batteries (LIBs). Citrus fruit juice (CJ) can provide an excellent chemical combination to remove the binder and support the leaching with efficiency in between 94% to 100%. CJ have many advantages in LIBs recycling as an economic and green method due to rich in many organic acids like citric and malic acid as complexing agents with ascorbic acid and citrus flavonoids, for the reduction of many heavy metals. Application of CJ can avoid the use of N-Methylpyrrolidine, γ-Butyrolactone, dimethylformamide, and dimethyl sulfoxide like toxic solvents commonly used for peeling off Al/Cu. Furthermore, counterions (like Na+, Mg+, Ca2+) present in CJ was responsible for the improvement in the leaching efficiency of organic acids. A mechanistic pattern of the overall reaction was also proposed and duly supported by various spectroscopic techniques. Binder removal experiment was supported by analytical techniques like XRD, XRF, IR, and FE-SEM, while the metal concentration was monitored by using ICP-MS analysis.
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