Stepwise Separation and Recovery of Metal Ions from Waste LiNi0.5Co0.2Mn0.3O₂ Batteries Using a NaA Zeolite

The development of electric vehicles and the depletion of related metal resources have made it imperative to recycle lithium-ion batteries. Nevertheless, there is still a lack of a simple, efficient, and green recycling method for metal separation from the leach solutions of waste lithium-ion batteries in industry. In this work, the effective separation and recovery of Li, Mn, Ni, and Co metals in the leach solutions are achieved through NaA zeolite ion exchange. The effects of the exchange temperature and zeolite concentration on the selective metal separation are systematically studied and the stepwise separation process of Mn, Co and Ni is realized under the effective enrichment of Li+. The recovery of Mn or Mn and Co or Mn, Co, and Ni ions is achieved by changing only the temperature or NaA concentration. More importantly, through the stepwise addition of NaA zeolite, high selectivities of 93%, 94%, and 99% for the recovery of Mn2+, Co2+, and Ni2+, respectively, can be achieved to obtain the corresponding MnA, CoA, and NiA zeolites. Finally, more than 95% of Li+ is effectively enriched. The adsorption kinetics and thermodynamics of NaA ion exchange show different adsorption rates and selectivities in the order of Mn2+ > Co2+ > Ni2+ > Li+. Therefore, the efficient separation and recovery of metal ions from the leach solutions of waste lithium-ion batteries can be achieved through NaA zeolite ion exchange, which contributes to the development of green and efficient separation technologies.