Järnhydroxykomplex

Järnhydroxykomplex is a chemical compound that refers to a complex of iron in its +3 oxidation state with hydroxide ions. This substance is often encountered as a brown precipitate in aqueous solutions containing ferric ions and a base. Its precise chemical formula can vary depending on the conditions of formation and stoichiometry, often being represented as Fe(OH)3 or more generally as FeO(OH)·nH2O, indicating a hydrated iron(III) oxyhydroxide.

The formation of järnhydroxykomplex is a common reaction in water treatment processes, particularly when removing iron from drinking water. Oxidation of dissolved ferrous iron (Fe2+) to ferric iron (Fe3+) is followed by hydrolysis and precipitation of the järnhydroxykomplex. This precipitate is then typically removed through sedimentation and filtration. In geological contexts, iron oxyhydroxides, which are closely related to järnhydroxykomplex, are important components of various iron ores and contribute to the red coloration of soils. Its physical properties include being insoluble in water and having a relatively high density.