Eco-Friendly Organic Acid-Assisted Mechanochemical Process for Metal Extraction from Spent Lithium-Ion Batteries

Abstract

This work represents a combination of mechanochemistry with eco-friendly low-cost natural organic acids to recover metal ions from spent lithium-ion battery (LIB) cathode materials. The effects of various reaction parameters on the metal extraction efficiency during the mechanochemical process were investigated. The results showed that under the optimal recovery conditions, that is, 2 mL of H2O2, mass ratio of LiCoO2 (LCO) to alginic acid of 1:10, rotation speed of 500 rpm, and grinding time of 4 h, the recovery efficiencies of Li and Co were 97.58 and 98.59%, respectively. The reaction mechanism of the mechanochemical process was discussed and verified. LCO combines with alginic acid and converts into water-soluble alginate under the action of a mechanical force and a reducing agent, and the metal ions are extracted and recovered in the subsequent water leaching process. In addition, the preliminary environmental and economic evaluation of the recycling process was assessed. The mechanochemical route proposed in this work can achieve green, efficient, and low-cost recovery of cathode scrap, which is a prospective guideline for the future industrial recycling of spent LIBs.