Extraction of nickel from cathode material of lithium-ion batteries using pyroligneous acid

Abstract. The study aims to investigate the potential use of pyroligneous acid (PA) in extracting nickel from the cathode active material of lithium-ion batteries (LIBs). The efficiency of nickel leaching was assessed by varying extraction temperature, time, and solid-to-liquid ratio. Optimal conditions were determined to be at 70 ℃, 30 minutes, and a solid-to-liquid ratio of 20 g/L. Under these conditions, PA was able to extract up to 95% of nickel from the cathode active material. Kinetic studies revealed that nickel extraction by PA follows a chemical reaction control mechanism with an apparent activation energy of 31.8 kJ/kmol. Results from this study suggest that PA can be an cost-effective and efficient organic alternative to the harmful inorganic lixiviant commonly involved in the hydrometallurgical process of spent LIBs.