What Is Muriatic Acid?

What You Need to Know About Muriatic or Hydrochloric Acid

muriatic acid
This is a space-filling model of muriatic acid, HCl. Muriatic acid typically is sold as a colorless liquid. Laguna Design / Getty Images

Muriatic acid is one of the names for hydrochloric acid. It is also known as spirits of salt or acidum salis. "Muriatic" means "pertaining to brine or salt". The chemical formula for muriatic acid is HCl.

Uses of Muriatic Acid

Muriatic acid has many commercial and home uses, including:

  • industrial synthesis of vinyl chloride and polyvinyl chloride (PVC)
  • food additive
  • gelatin production
  • descaling
  • leather processing
  • household cleaning (when diluted)
  • pickling of steel
  • production of inorganic chemical compounds
  • pH control of water, food and drugs
  • regenerating ion exchange resins
  • purification of table salt
  • building construction
  • to dissolve rock in oil production
  • occurs naturally in gastric acid to digest food

Muriatic Acid Production

Muriatic acid is prepared from hydrogen chloride. Hydrogen chloride from any of a number of processes is dissolved in water to yield hydrochloric or muriatic acid.