Ultrasound-assisted efficient and convenient method of extracting valuable metals (Ni, Co, and Cd) from waste Ni–Cd batteries using DL-malic acid

Recycling waste Ni-Cd batteries has received much attention recently because of the serious environmental pollution they cause and to avoid the dissipation of valuable metals. Despite significant research, it is still difficult to efficiently recycle valuable and hazardous metals from waste Ni-Cd batteries in an economical and environmentally friendly manner. This study employed a novel process utilizing ultrasound-assisted leaching to recover Ni, Cd, and Co from waste nickel-cadmium (Ni-Cd) batteries. Organic DL-malic acid served as the leaching agent and H