ferriklorid

Ferric chloride, or ferriklorid, is the inorganic compound with the formula FeCl3. In its anhydrous form it is a dark brown hygroscopic solid; the more common form in laboratory and industrial settings is the hexahydrate FeCl3·6H2O, which appears as yellow-brown crystals.

Ferric chloride is produced commercially by direct reaction of iron with chlorine: 2 Fe + 3 Cl2 → 2 FeCl3. It can also be obtained by dissolving iron in chlorine-containing acids. The compound is highly hygroscopic and readily hydrolyzes in moist air.

In water the compound behaves as a strong Lewis acid and hydrolyzes to yield ferric oxyhydroxide and hydrochloric acid: FeCl3 + 3 H2O → Fe(OH)3 + 3 HCl. In concentrated chloride solutions it forms chloro-complexes such as FeCl4−. Solutions are acidic and the iron center can participate in various coordination environments.

Major uses include etching copper in printed circuit board production, coagulation and removal of impurities in municipal and industrial water treatment, and catalysis in organic synthesis (notably Friedel–Crafts reactions), as well as mordanting and dyeing applications.

Ferric chloride is corrosive and irritating to skin and eyes; inhalation may irritate the respiratory tract. It should be stored in a dry, tightly closed container away from moisture and incompatible substances. Handling requires proper safety equipment, including gloves and eye protection.