Cobalt acetate is a purple-red deliquescent crystal with a slight acetic acid odor. It is heated to 140 C to form anhydrous substance. It is soluble in water, ethanol, dilute acid and amyl acetate. Its relative density is 1.705 and refractive index is 1.542. It has the possibility of carcinogenesis.
The preparation methods of cobalt acetate are as follows:
1.Metal Cobalt or Cobalt Oxide Method
The cobalt nitrate solution is prepared from cobalt metal or cobalt oxide by reaction with nitric acid, and then reacts with ammonium bicarbonate (or soda) solution to form cobalt carbonate precipitation. Cobalt acetate can be obtained by washing and separating the precipitation and adding acetic acid to acidify it. After filtration, the reaction solution is adjusted to pH=2 and concentrated to the relative density of the solution is 1.17-1.20. Then 1 kg acetic acid is added to every 200 L concentrated solution, at a low level. The final product was obtained by crystallization at 20 ~10 days, centrifugal separation and drying at 30~40 ~C.
2. Cobalt Sulfate Method
Cobalt sulfate reacts with soda to form cobalt carbonate, which reacts with acetic acid. The product is obtained by filtration, concentration, crystallization, dehydration and packaging.
3. Take 5g cobalt nitrate hexahydrate and add it to 25ml acetic anhydride, mix evenly, boil for 10 minutes, and precipitate through stationary crystal. Drainage and washing with a small amount of acetic anhydride and ether. The product can be obtained by vacuum drying at 100 C for 1 hour.