Recovery of nickel from spent NiCd batteries by regular and ultrasonic leaching followed by electrodeposition

Abstract

This study focuses on the hydrometallurgical route of separating Ni metal from spent nickel cadmium (NiCd) batteries. The comparison of separation of nickel metal with the assistance of ultrasonic leaching and regular leaching was performed. Sulphuric acid (solvent) was used as the lixiviant to leach out the nickel metal ions from the spent battery and the parameters affecting the leaching with and without ultrasonication were optimized. The major parameters affecting the leaching process are volume of solvent, concentration of lixiviant and leaching time. The electrodeposition of nickel metal ions from ultrasonically assisted and regular leaching was carried out at an optimized current density of 8 A dm-2, contact time of 4 hours and the concentration of lixiviant of 5 M. It was observed that the recovery efficiency for ultrasonically assisted leaching followed by electrodeposition is 98.5 %, while in regular leaching followed by electrodeposition is 90.8 %.

Keywords

• Electrodeposition
• leaching
• spent battery
• ultrasonication