Leaching of Critical Metals from Spent Lithium-Ion Battery Using Acidic Organophosphorus Extractant

Recycling of cathode material of spent lithium-ion batteries (LIBs) is important for recovering critical metals and protecting the environment. This study thus proposes a sustainable recycling process for cathode material (nickel-cobalt-manganese/NCM chemistry) via leaching with an acidic organophosphorus extractant, di-(2-ethylhexyl)phosphoric acid/D2EHPA and copper (current collector) as the reducing agent. The effects of leaching parameters, including stirring speed, Cu amount, D2EHPA concentration, temperature, and time were investigated. The leached metals on the loaded D2EHPA were recovered via stripping using pH-controlled aqueous solutions. Using D2EHPA for leaching allows process intensification because it integrates leaching and solvent extraction (SX) in one-stage operation. It also reduces the consumption of aqueous solutions, thereby minimizing wastewater generation.