Calcium ferrocyanide

Calcium ferrocyanide is a chemical compound with the formula Ca2[Fe(CN)6]·11H2O. It is a yellow crystalline solid that is soluble in water and insoluble in alcohol. Calcium ferrocyanide is used in a variety of applications, including as a food additive, in the production of pigments, and in the treatment of metal surfaces.

Chemical properties

Calcium ferrocyanide is a coordination compound, which means it is formed by the combination of a metal ion (in this case, calcium) with a group of non-metal ions (in this case, the ferrocyanide ion, [Fe(CN)6]4-). The compound is stable under normal conditions, but it can decompose under high heat to produce toxic fumes of hydrogen cyanide and nitrogen oxides.

Uses

One of the main uses of calcium ferrocyanide is as a food additive. It is used as an anti-caking agent in table salt and other dry foods to prevent the formation of lumps. In the European Union, it is designated as E number E538.

Calcium ferrocyanide is also used in the production of pigments. It is used to produce Prussian blue, a dark blue pigment that is used in paints, inks, and dyes.

In addition, calcium ferrocyanide is used in the treatment of metal surfaces. It is used as a corrosion inhibitor in the pickling of steel and other metals.

Safety

Calcium ferrocyanide is generally considered safe for use in food. However, it can be harmful if swallowed in large amounts or if it comes into contact with the skin or eyes. It can also be harmful if inhaled, as it can decompose to produce toxic fumes.

See also

• Ferrocyanide
• Calcium cyanide
• Food additive