rautafosfaattia

Rautafosfaatti, or iron phosphate, refers to a family of inorganic compounds consisting of iron ions combined with phosphate. The principal forms are iron(III) phosphate (FePO4) and iron(II) phosphate (Fe3(PO4)2). Natural minerals include strengite, the hydrated iron(III) phosphate FePO4·2H2O, and vivianite, the iron(II) phosphate hydrate Fe3(PO4)2·8H2O.

Industrial preparation typically involves precipitating iron phosphate by neutralizing phosphoric acid with iron salts, followed by drying. Iron phosphates also occur as corrosion products and as byproducts in steelmaking and in processing of phosphate rocks.

Rautafosfaatti has a variety of applications. It is used as a corrosion inhibitor and as a phosphate conversion coating for metal surfaces such as steel and aluminum. It serves as a cathode material in lithium iron phosphate (LiFePO4) batteries. In pigment and ceramic industries, iron phosphate compounds function as colorants. As a micronutrient, iron phosphate (ferrous phosphate) can be used as an iron source in fertilizers and fortification of food products. It is also employed as a molluscicide for slug and snail control under the name ferrous phosphate.

Safety and regulation indicate that iron phosphates are generally of low toxicity when used appropriately; insoluble salts can irritate skin, eyes, and the respiratory tract. As with other chemical substances, usage in agriculture, food, and industrial contexts is governed by applicable safety and labeling requirements.

See also: ferric phosphate, ferrous phosphate, LiFePO4, phosphate conversion coatings.