Potassium hexacyanoferrate iii trihydrate
| Chemical formula | K3[Fe(CN)6] |
| Density | 1.852.1 g/cm3 (20°C) |
| Molar mass | 329.26 g/mol |
| Bulk density | ~900 – 1000 kg/m3 |
| CAS number | 13746-66-2 |
| HS Code | 28372000 |
| EC number | 237-323-3 |
| Storage | Without limitation |
| SDS | available |
| RTECS | LJ8225000 |
| Odour | odourless |
| Form | solid |
| Color | darck red |
| p H | ~6 (50g/l 20 °C) |
| Solubility in water | 464 g/l (25°C) |
| Thermal decomposition | 300 °C |
| Assay | ≥ | 99 | % |
| Description | Conforms | ||
| Identification | Conforms | ||
| Solubility | Conforms | ||
| Chloride | ≤ | 0.15 | % |
| Sulfate | ≤ | 0.01 | % |
| Hexacyanoferrate | ≤ | 0.1 | % |
Potassium hexacyanoferrate(III) trihydrate is a bright red, crystalline coordination compound containing iron in the +3 oxidation state. It is known for its stability, solubility in water, and use in both analytical and industrial chemistry as an oxidizing agent and complexing compound.
🏭⚗️ Production
Potassium hexacyanoferrate(III) trihydrate is produced by oxidizing potassium hexacyanoferrate(II) with chlorine or other oxidizing agents in aqueous solution. The resulting red solution is concentrated and cooled to crystallize the trihydrate form. The compound is carefully prepared under controlled conditions to maintain the integrity of the iron-cyanide complex and ensure high purity.
🔬 Properties
The chemical formula of potassium hexacyanoferrate(III) trihydrate is K₃[Fe(CN)₆]·3H₂O, with a molar mass of approximately 422.33 g/mol. It forms deep red crystals that are readily soluble in water but insoluble in alcohol. The compound is thermally stable under normal conditions but can decompose when heated strongly, releasing toxic fumes such as hydrogen cyanide. It is sensitive to light and should be stored in a dark, dry place. In aqueous solution, it acts as a moderate oxidizing agent.
🧪 Applications
Potassium hexacyanoferrate(III) trihydrate is widely used in analytical chemistry, particularly in redox titrations and spot tests for various metal ions. It is also employed in the manufacture of pigments such as Prussian blue and in the treatment of metals for corrosion protection. In photochemistry, it is used in blueprinting and light-sensitive papers. Additionally, it is utilized in electroplating and as an oxidizer in some industrial processes.
⚠️ Safety
Although the cyanide ligands in potassium hexacyanoferrate(III) are strongly bound to the iron center and not readily released under normal conditions, the compound should still be handled with care. It may cause irritation to the skin, eyes, and respiratory tract. Decomposition under strong acids or high heat can release toxic hydrogen cyanide gas. Protective equipment, such as gloves and safety goggles, should be used, and the compound must be stored away from acids and light in a secure, dry environment.
