Formiates

Formiates are salts or esters of formic acid. Formic acid, with the chemical formula HCOOH, is the simplest carboxylic acid. Formiates are characterized by the formate anion, [HCOO]−, or by the ester group -OCHO. The formate ion is planar, with the carbon-oxygen bonds having intermediate character between single and double bonds. Many formiates are soluble in water.

Common examples of formiates include sodium formate (HCOONa) and potassium formate (HCOOK). Sodium formate is a white crystalline solid that is hygroscopic. It is produced industrially from carbon monoxide and sodium hydroxide. Potassium formate is also a white crystalline solid and is often used as a de-icing agent for runways due to its low freezing point and biodegradability. Methyl formate (HCOOCH3) and ethyl formate (HCOOCH2CH3) are examples of formate esters. Methyl formate is a volatile liquid with a pleasant odor and is used as a fumigant. Ethyl formate is also a volatile liquid and is used as a solvent and in flavorings.

Formiates have various industrial applications. They are used in the production of other chemicals, as reducing agents, and in the leather tanning industry. In some biological contexts, formates are important metabolic intermediates. For instance, certain bacteria can produce formic acid as a byproduct of fermentation, which can then be converted to formate ions.