Cobalt oxalate dihydrate

Cobaltous oxalate dihydrate, CoC 04-2H 0 tpink). is obtained by adding oxalic acid or an alkaline oxalate to a cobaltous salt solution. This is the commercial form of tile salt and is important as the starting material in ihe preparation of cobalt metal powders. 

Mesocrystals can even be formed without additive, as foimd for the related cobalt oxalate dihydrate [126]. Copper oxalate crystals were composed of nanometer building units and strings of nanodomains oriented along the principal axis of the particle were detected, revealing that the lateral and basal faces of the precipitate are composed of stacked nanoparticle layers with a thickness of 5-7 nm. 

Urea (3.2 g, 53 mmol), (NH4)2Mo04 (0.126g, 0.6 mmol), and pyridine-2,3-dicarboxylic acid (l.Og, 6 mmol) were ground together until homogenous. The lnixlure was stirred in 1,2,4-trichlorohenzene (40 mL) for 1 h at 156-160=C. A ground mixture of cobalt(II) oxalate dihydrate (1.1 g, 6 mmol) and urea (2.5 g, 42 mmol) was slowly added under N2. The temperature was maintained at 205-210 C for 3.5 h. On completion, excess 1,2,4-trichlorobenzene was removed by distillation under reduced pressure. The crude product was washed with benzene (100 mL), crushed and washed successively with EtOH, warm H20, warm 5% aq NaOH, warm H20, warm 2.5% HC1, and warm H20, and dried at 80 C yield 0.882 g (45%). 

Cobalt(ll) oxalate dihydrate COC204 2H20 6966-38-8 182.982 pink needles dec 0.0037 si acid s NH4OH... 

Cobalt(II) oxalate [814-89-1], C0C2O4, is a pink to white crystalline material that absorbs moisture to form the dihydrate. It precipitates as the tetrahydrate on reaction of cobalt salt solutions and oxaUc acid or alkaline oxalates. The material is insoluble in water, but dissolves in acid, ammonium salt solutions, and ammonia solution. It is used in the production of cobalt powders for metallurgy and catalysis, and is a stabilizer for hydrogen cyanide. 

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