Cryatallizing-stripping of Sm(III) and Co(II) as Composite Oxalates and Their Physical Properties. Studies on production of composite powders with crystallization stripping. (1st Report).

Abstract

A selection method of an extractant and a precipitant to be effective in crystallization-stripping was investigated by using a relation between the extraction-stripping behavior of metal ions from the organic phase containing an extractant and the solubility of insoluble metal salts such as metal carbonates and metal oxalates. The uniformly mixed metal composite powders, which had a controlled particle size and shape, were produced by the crystallization-stripping of two metal ions from the organic phase. The objective product was the metal composite powders of samarium and cobalt as a magnetism material.An extractant and a precipitant to be effective can be selected in crystallization-stripping by investigating the relation between a stripping condition of metal ions from the organic phase and the solubility of metal salts. Versatic Acid 10 and oxalic acid are a good combination in crystallization-stripping of Sm(III) and Co(II). The crystallization-stripping reaction of Sm(III) and Co(II) from Versatic Acid 10 is fast, and Sm(III) and Co(II) in the organic phase are recovered more than 96 % as metal oxalates in 5min reaction time. The recovery and particle shape of samarium-cobalt oxalates are affected by aqueous pH and agitation speed. With oxlaic acid solution at pH2 ~ 6, Sm(III) and Co(II) in the organic phase are completely recovered as metal oxalates. Samarium-cobalt oxalate composite powders obtained at 600 rpm agitation speed are the uniformly mixed powders with the objective composition.