Chromatographic separation of Li, Ni, Co and Mn by functionalized fiber towards spent lithium-ion battery recycling

The rapid growth of the new energy market has led to a substantial increase in the demand for ternary lithium batteries, highlighting the importance of recycling their cathode materials to mitigate environmental risks and alleviate the limited supply of valuable metals. Traditional recycling methods for waste ternary lithium batteries are often inefficient and energy-intensive, particularly in recovering lithium. This study proposes a novel process for the separation and recovery of Li, Ni, Co, and Mn from simulated spent ternary lithium battery cathode materials. The process employs chromatographic separation and column operation techniques using amine-modified polyacrylonitrile fibers as adsorbents, which have selective adsorption capacity for Li with transition metals Ni, Co, and Mn. Experimental results demonstrated a lithium recovery rate of 99.4 % with 100 % purity under optimized conditions: solution pH of 2, feed solution concentration of 10 mmol/L, a fully packed adsorption column, and a feed flow rate of 0.29 mL/min. During the elution process, 0.2 mol/L nitric acid achieved effective desorption of the adsorbed metals. Furthermore, the intermetallic separation coefficients revealed significant separation efficiencies for Ni, Co, and Mn. This proposed method offers notable advantages in recovery efficiency, selectivity, and environmental sustainability, with particularly outstanding performance in lithium recovery, making it a promising strategy for recycling valuable metals from spent ternary lithium batteries.