Formic Acid


IUPAC name: Methanoic acid
Other names : Methanoic acid, hydrogen carboxylic acid, aminic acid, formylic acid
CAS number: 64-18-6

Formic acid is the simplest organic acid and is present in large quantities in animals and plants. Ants, whose organism synthesises it, and to which it owes its name, utilise it in their defence mechanism as a stinging agent; it is also found in plants like the common nettle. It is made from carbon monoxide and water.
It is a colourless liquid with a pungent smell; it is corrosive and it causes burns if it is kept in contact with the skin. It is miscible with glycerol, ethyl acetate, methanol, and water; it is highly soluble in acetone; it is a strong reducing agent; it decomposes easily into carbon oxides and water in the environment; several catalysts, specifically the platinum group metals, cause the decomposition of formic acid into carbon dioxide and water even at room temperature.

Principal uses

Formic acid is an important compound in the chemical and pharmaceutical industry because of its acid and reducing properties:

  • preservation of biological material;
  • preservation and antibacterial agent in industrial feed;
  • preparation of acid baths in the fibre dying processes (polyamides, polyesters, acrylics, cotton, wool, triacetates, rayon; ramie, silk, etc.) and in leather tanning and dying;
  • disinfection of cotton, rayon, and wool (fast-acting: acid dissociation constant at 298 K: Ka= 1.77 x 10-4);
  • natural rubber manufacture;
  • acidity control and cleaning in processes requiring a very low environmental impact and that do not allow residues.