A Study on the Preparation of Rare Earth Oxide Powder for Rare Earth Precipitates Recovered from Spent Ni-MH Batteries

We report a method for preparing rare earth oxides ( $Re_xO_y$ ) from the recycling process for spent Ni-metal hydride (Ni-MH) batteries. This process first involves a leaching of spent Ni-MH powders with sulfuric acid at $90^{\circ}C$ , resulting in rare earth precipitates (i.e., $NaRE(SO_4)_2...