Recovery of cobalt and nickel from spent lithium ion batteries with citric acid using leaching process: Kinetics study

Lithium ion batteries are commonly used as power sources for mobile phone, but by using it continually will degrade their capabilities. Battery replacements will cause a lot of waste in environment. Spent lithium ion batteries cathode contain heavy metals, such as cobalt and nickel. However it is also included as valuable metals thus recovery process is necessary. In this research, hydrometallurgical leaching process has been done for recovery of cobalt and nickel from spent lithium ion batteries using citric acid as a leaching agent by varying citric acid concentration (0.5-1 M), reaction temperature (50-80 degrees C) and reaction time (5-20 minutes). The spent lithium ion batteries were analyzed by atomic absorption spectroscopy (AAS). The result showed that the leaching of lithium ion batteries using citric acid was depend on citric acid concentration, reaction temperature and reaction time. Based on kinetics study, the leaching reaction of cobalt and nickel from cathode powder using citric acid was chemically controlled process and the activation energy of cobalt and nickel were 67.12 kJ/mole and 58.22 kJ/mole. The reaction order of leaching cobalt and nickel using citric acid was first-order reaction.