New Technology Recovers 90% of Nickel, Cobalt

Japan’s Mitsui Mining & Smelting Co. and Sumitomo Metal Mining Co. have jointly developed technology for recovering nickel, cobalt and rare-earth metals from nickel-metal hydride batteries used in hybrid vehicles, reports The Nikkei Business Daily. The technology can recover 98.5% of the nickel, 96% of the cobalt, and 98% of the rare-earth mixture.

The batteries are first chilled to -196C to keep chemical reactions from occurring, then are crushed and stirred into water. Exploiting the fact that the speed at which materials precipitate in water depends on particle size, the material is sorted into fine and coarse particles.

The coarse particles contain large quantities of nickel and cobalt, which are extracted by immersing the particles in sulfuric acid and using solvents. The fine particles tend to contain lanthanum, cerium and other rare-earth metals, and a mixture of these is recovered.

The Japan Oil, Gas and Metals National Corp. also participated in development.