raudtrikloriid

Raudtrikloriid, also known as iron(III) chloride or ferric chloride, is a chemical compound with the formula FeCl3. It exists as an anhydrous solid or as a hydrated solid, most commonly as the hexahydrate, FeCl3·6H2O. Anhydrous iron(III) chloride is a dark crystalline solid, while the hexahydrate forms yellowish to brownish crystals.

The compound is highly soluble in water, producing acidic solutions due to hydrolysis. It is also soluble in many organic solvents, such as ethanol and acetone. Iron(III) chloride is a Lewis acid and readily forms complexes with ligands. Its chemical reactivity makes it useful in various industrial applications.

Industrially, iron(III) chloride is produced by the direct chlorination of iron metal or by the reaction of iron oxides with hydrochloric acid followed by oxidation. Its primary uses include wastewater treatment as a coagulant and flocculant to remove impurities. It is also employed in the etching of copper in the production of printed circuit boards and as a catalyst in organic synthesis. In medicine, it has been used historically as an astringent.