Abstract: A process for treating an AB.sub.5 Ni--MH battery to recover purified positive and negative electrode components of the battery is disclosed. An AB.sub.5 Ni--MH battery is placed in a mineral acid leach solution to cause the positive and negative electrode components of the battery to separate. The positive and negative electrode components are maintained in the leach solution until the negative electrode component breaks down into its dissolved rare earth metal constituents and metallic solids. The metallic solids remaining from the negative electrode component and the positive electrode components are separated from the mineral acid leach solution and subjected to an elutriation process and thereafter to ball milling to obtain Ni rich powder and Fe. The mineral acid leach solution containing the completely dissolved rare earth metals is subjected to a phosphate precipitation process to recover La and Ce in precipitate, and then subjected to a second precipitation process to recover Ni, Co, Mn and Al.

Abstract: A method of treating a mixture of Nd.sub.2 Fe.sub.14 B and SmCo.sub.5 alloy scrap or waste particulates wherein the mixture is introduced to a bath of sulfuric acid solution to selectively dissolve the Nd.sub.2 Fe.sub.14 B alloy particulates, leaving a majority of the SmCo.sub.5 alloy particulates undissolved. Hydrogen bubbles are generated in the bath by dissolution of the Nd.sub.2 Fe.sub.14 B alloy particulates. The undissolved SmCo.sub.5 alloy particulates adhere to the hydrogen bubbles are floated to the bath surface to form a froth containing a concentrate of the SmCo.sub.5 alloy particulates, which are recovered by removing the concentrate from the bath surface. The bath is treated to recover the Nd metal of the dissolved Nd.sub.2 Fe.sub.14 B alloy particulates. Any grinding media present in the mixture settles to the bottom of the bath to further upgrade the recovered alloy product.

Abstract: A method of treating rare earth-transition metal alloy scrap involves in one embodiment dissolving the scrap in aqueous sulfuric acid solution, reacting the solution with a hydroxide of an alkali element (e.g., Na or K) or ammonium to precipitate a double sulfate salt of the rare earth and the alkali element or ammonium, and separating the salt from the solution. The double sulfate salt is converted to a rare earth salt, such as rare earth fluoride, amenable for use in metallothermic reduction processes to make rare earth metal or alloys.

Abstract: A door for closing vehicular traffic passages is provided in which the door is a curtain fabricated from a hard flexible material. The curtain runs in opposing channels, is mounted on a counterbalanced wind-up drum and under impact changes weight, moves out of the channels and is wound up to open the vehicular passage.