Cobalt(II) hydroxide

Description: Cobalt hydroxide is a fine inorganic compound, generally rose-red monoclinic or tetragonal crystal, decomposed by heating at a relative density of 3.597 (15 ° C). Soluble in acid and ammonium salt solution, insoluble in water and ethanol. Reacts with some organic acids to form a cobalt-containing soap. Easy to decompose when heated. It was dehydrated to CoO by heating at 160 ° C in a vacuum. It is more active and can react to form a salt in a weak acid aqueous solution. In the presence of oxygen, the reaction rapidly changes to a high-priced state. It is generally prepared by reacting a cobalt salt with an alkali metal hydroxide or by using cobalt as an anode to electrolyze brine. It is used as a raw material for cobalt salt, as a desiccant for paints and varnishes, as a saturated liquid for batteries, as a catalyst for decomposition of H2O2.

Properties: There are two types of cobalt hydroxide, one is unstable α-cobalt hydroxide, its color is dark green, and the other is relatively stable β-cobalt hydroxide, which is a rose-red powder.

The molecular formula of cobalt hydroxide is Co(OH)2.

Density (g/mL, 25/4 ° C): 3.597,

Insoluble in water, soluble in acid and ammonium salt solution, easily oxidized to Co(OH)3 by air or weak oxidant and turned brown, dehydrated in vacuum to form CoO.

Figure 1 shows the structure of cobalt hydroxide

Preparation: Cobalt hydroxide is mainly prepared by using cobalt chloride, cobalt sulfate and other cobalt salts with NaOH such as sodium hydroxide and ammonia. The basic reaction principle is as follows: Co2+ + 2OH- → Co(OH)2 Overview and properties of cobalt hydroxide Preparation, use is organized by the editor of the Chemicalbook. (2015-11-16)

Uses: used in the preparation of cobalt salt raw materials, as a desiccant for coatings and varnishes, cobalt catalysts, saturated liquids for batteries, catalysts for the decomposition of H2O2, as a coloring agent for the glass industry.

Toxicity: It is a biologically important element. Small doses can activate many enzymes that regulate tissue respiration, hematopoiesis and other processes. At high doses, they inhibit the activity of these enzymes, affect carbohydrate metabolism, and selectively damage the endocrine of the pancreas. Partly, it affects the cardiovascular system, dilates blood vessels, lowers blood pressure, and selectively damages the heart muscle. Inhalation of cobalt compounds, sometimes bronchial asthma. Grinded cobalt compounds can cause acute dermatitis, sometimes forming ulcers on the surface. The maximum allowable concentration of metallic cobalt and cobalt oxide is 0.5 mg/m3. Respiratory masks, dust-proof overalls, and protective gloves should be used during work to protect the respiratory organs and skin. When working with metal cobalt dust at work, it is recommended to wash your hands with a paste. Dust and dust should be paid attention to during production, and wet operation should be adopted.

Chemical properties: rose red orthorhombic crystal or powder. Do not dissolve in water, soluble in acid and ammonium salt solution.

Uses: Used in cobalt salt, cobalt catalyst, battery electrode impregnation solution and paint desiccant

Uses: Used in glass, enamel coloring, cobalt compounds, and desiccants for paints and varnishes.

Uses: Used in the manufacture of cobalt salt raw materials, coatings and varnish desiccants, hydrogen peroxide decomposition catalysts.

Production method: Cobalt-containing waste method Various cobalt-containing wastes are dissolved by nitric acid and hydrochloric acid, and the obtained cobalt chloride solution is purified by hydrogen peroxide to remove iron, and if necessary, sodium carbonate or ammonia water is added to ensure complete purification. The purified cobalt chloride solution is added with sodium hydroxide to form cobalt hydroxide, and then washed and centrifuged to obtain a cobalt hydroxide product. Co+2HCl→CoCl2+H2 CoCl2+2NaOH→Cu(OH)2+Na2SO4

Category: Toxic substances

Flammability Hazardous Characteristics: Non-combustible, toxic cobalt oxide fumes emitted from fire sites

Storage and transportation characteristics: warehouse low temperature, ventilation, drying

Extinguishing media: water, carbon dioxide, dry powder, sand

Cobalt hydroxide safety information:

Dangerous goods mark :Xn,N

Hazard Category Code : 20/21/22-36/37/38-50/53-42/43-40-20/22

Safety instructions :26-37/39-36

Dangerous goods transport number : UN 3077 9 / PGIII