硫酸コバルト(II)

用途化学物質製造段階の触媒

用途他のコバルト塩と同様、ガラスや陶磁器の彩色用顔料となる他、電池や電気めっき、不可視インク原料としての用途もある。ミネラル補給目的で、飼料に添加される。かつては泡の安定を目的としてビールに添加されたり、貧血の治療薬としても用いられた。

説明The blue, crystalline hydrate Co2(SO4)3.18H2O is prepared by the oxidation of cobalt(II) sulphate in 8N sulphuric acid either electrolytically or chemically with ozone or fluorine. It is stable in the dry state, but is decomposed by water with evolution of oxygen; it is fairly stable in solution in dilute sulphuric acid. Cobalt(III) alums MCo(SO4)2.12H2O (M = K, Rb, Cs or NH4) can be isolated as blue crystals from the mixed cooler solutions of the two sulphates in dilute sulphuric acid. The potassium alum is diamagnetic, the rubidium salt has a magnetic moment less than 1 B.M. and the ammonium alum has a moment of 2.1 B.M. at 304°K. The hydrated sulphate also has a small positive magnetic susceptibility. The sulphate is believed like the alums to contain the [Co(H2O)6]3+ ion.

使用Ceramics, pigments, glazes, in plating baths for cobalt, additive to soils, catalyst, paint and ink drier, storage batteries.

一般的な説明Odorless rose-pink solid. Sinks and mixes with water.

純化方法Crystallise it three times from conductivity water (1.3mL/g) between 100o and 0o depending on which hydrate is required. The heptahydrate crystallises below 44o and is efflorescent with m 97o . Between 44o and 70o the monoclinic hexahydrate CoSO4.6H2O m 41.5o is formed, and above 70o the monohydrate CoSO4.H2O m 71o is obtained. The pale reddish or lavender-coloured anhydrous salt is obtained by heating the hydrate above 250o, boiling with conc H2SO4 or heating with (NH4)2SO4).