Nickelous hydroxide from aqueous nickel - chloride and alkol nickel chloride and

摘要

Pure Ni(OH)2, useful for +ve Ni electrodes of alkali accumulators is precipitated from an aqs. NiCl2 solution by stirring with an alkali amalgam containing 0.1-0.4 wt. % alkali metal in a reaction vessel using a Ni-plated stirring device. Pref. alkali amalgam is led into reaction vessel below 80 degrees C using NiCl2 solution of 0.5-1 molar concn. Pref. alkali amalgam is removed as partial stream from Hg electrode of an alkali electrolysis cell and led, evenly divided, into NiCl2 solution, while Hg collecting on bottom of reaction vessel is recycled to Hg electrode. Apparatus pref. consists of vertical cylindrical reaction vessel, pref. of Ni or with Ni-plated walls, provided with driven roller fitted with large-area Ni or Ni-plated stirrer blades, and a perforated disc distributor for alkali amalgam, which is pref. situated over NiCl2 solution surface.