Resource Recovery from Nickel-plating Waste Fluid Using Intense Magnetic Field of Superconducting Bulk Magnet

Abstract

Three kinds of magnetic separation technique utilized to recycle nickel from the waste fluid of electroless plating processes are introduced in the article, with reference made to HTS bulk magnet systems activated by pulsed-field magnetization and field cooling methods. Actual magnetic separation experiments were conducted using Ni-based coprecipitated slurry, thermally-docomposed Ni-P metallic particles, and coarse NiSO₄ crystals in the regenerated fluid from Nickel phosphite slurry, which were all processed from the Ni-plating waste. Through the investigations, the author refers to the feasibility of practical recycling of Ni as a rare metal with the use of HTS bulk magnets generating intense magnetic fields of 2-4 T.