Iron(II,III) Oxide - Uses

Uses

Fe₃O₄ is used as a black pigment and is known as C.I pigment black 11 (C.I. No.77499).

Fe₃O₄ is used as a catalyst in the Haber process and in the water gas shift reaction. The latter uses an HTS (high temperature shift catalyst) of iron oxide stabilised by chromium oxide. This iron-chrome catalyst is reduced at reactor start up to generate Fe₃O₄ from α-Fe₂O₃ and Cr₂O₃ to CrO₃.

Nano particles of Fe₃O₄ are used as contrast agents in MRI scanning Ferumoxytol is an intravenous Fe₃O₄ preparation for treatment of anemia resulting from chronic kidney disease.

Along with sulfur and aluminium, it is an ingredient in a specific type of thermite useful for cutting steel.

Bluing is a passivation process that produces a layer of Fe₃O₄ on the surface of steel to protect it from rust.