A Novel Green Process for Recovery of Transition Metal Ions from Used Lithium-ion Batteries by Selective Coordination of Ethanol

Abstract

As the abundance of end-of-life lithium-ion batteries continues to increase, it is significant to recover valued metals in an eco-friendly way, yet this remains a challenge. Based on a novel deep eutectic solvent (DES) consisting of betaine hydrochloride and lactic acid, we developed a combined DES–ethanol selective separation process for extracting valuable metals from spent LiCoO2 batteries, with a high efficiency. This process accomplished the complete leaching of lithium-ion battery (LIBs) cathode materials by DES. The selective separation of lithium and cobalt was accomplished by changing the coordination environment of transition metal ions in DES using ethanol. The strategy was also applicable to LiNi x Co y Mn1–x–y batteries with different compositions and efficiently achieved stepwise transition metal separation. Further, we analyzed in depth the detailed selective extraction mechanism. This green and high-efficiency recycling process is a promising candidate for recovering valuable metals from used LIBs. The proposed method is particularly attractive due to its high selectivity, considerable economic advantages, and environmental benefits.

The Recovery of Lignin from Reed Using Solid-DES Extraction (SDESE)

“…3441 cm −1 in LA. This red shift was similar to the shift reported previously for a DES formed of BeHCl:LA in the same ratio of 1:5 [18]. The flattened character of the corresponding band in BeHCl, which was almost absent due to less H-bonds, was not reflected in the DES spectrum, confirming that new and more abundant H-bonds were formed in the DES compared with both LA and BeHCl.…”

“…Most of the bands from BeHCl disappeared or were significantly reduced and shifted, with the spectrum of DES being very similar to that of LA, with small differences. The same was previously reported for BeHCl:LA without water [18]. The bands corresponding to the C-H bonds of alkyl groups were shifted in DES compared to LA: 2893/2897 cm −1 for the symmetric vibration of CH 2 and CH 3 and 2992/2989 cm −1 for the asymmetric vibration of CH 3 in DES/LA).…”

Reaction–Diffusion Coupling Facilitates the Sequential Precipitation of Metal Ions from Battery Feedstock Solutions

“…Specifically, 12.7% of the total Mn in the feedstock solution was recovered as a high-purity product in the final segment (position g). We note that the recovery rate of our method is lower than some reported methods, − partially due to the lower NaOH concentration compared to the metal-salt-containing feedstock. However, the selective precipitation of Mn was achieved without requiring organic solvents, heating, or specialty chemicals. , …”

Regenerating Spent Lithium-Ion Battery Cathodes as Dual-Functional Biocatalysts for Highly-Efficient Oxygen and Hydrogen Evolution Using Aspergillus niger Soluble Extracellular Polymers

“…The primary approaches for extracting valuable metals from SLIBs include pyrometallurgical, hydrometallurgical, and integrated processes. , In addition to traditional recycling techniques, there is a growing focus on exploring the utilitarian value of SLIB cathodes as raw materials . Recent research has illustrated that diverse microorganisms can effectively catalyze the reduction or conversion of metal ions in the leachate from waste materials (such as Ag + , Cr 6+ , Au 3+ , and Pb 2+ ) into biobased materials. , The exploration of microbial upgrading for cathodes of SLIBs is still in the early stages.…”