Recovery of valuable metals from industrial leachates of spent ni metal hydride batteries by precipitation processes
Résumé
The recycling of spent nickel metal hydride (Ni-MH) batteries from hybrid electric vehicles serves as an increasingly-attractive secondary source of critical materials thanks to the recent development of hydrometallurgical processes.[1,2] Ni-MH batteries contain multitude of âcriticalâ and âstrategicâ metals: La, Ce, Nd, Pr, Co, Mn, Ni, etc. and constitute a significant potential source of secondary raw materials with the marketing of approximately one billion cells every year for the past 15 years. Hydrometallurgical process consists in attacking the powders resulting from the grinding of batteries, by an acid (leaching step) to dissolve the elements in order to recover them by subsequent separation operations, such as precipitation.