Sponge iron reaction
Encyclopedia
The sponge iron reaction (SIR) is a chemical process based on redox
cycling of an iron-based contact mass, the first cycle is a conversion step between iron
metal (Fe) and wuestite (FeO), the second cycle is a conversion step between wuestite (FeO) and magnetite
(Fe3O4).
in combination with a steam reforming
unit.
Redox
Redox reactions describe all chemical reactions in which atoms have their oxidation state changed....
cycling of an iron-based contact mass, the first cycle is a conversion step between iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
metal (Fe) and wuestite (FeO), the second cycle is a conversion step between wuestite (FeO) and magnetite
Magnetite
Magnetite is a ferrimagnetic mineral with chemical formula Fe3O4, one of several iron oxides and a member of the spinel group. The chemical IUPAC name is iron oxide and the common chemical name is ferrous-ferric oxide. The formula for magnetite may also be written as FeO·Fe2O3, which is one part...
(Fe3O4).
Process description
The process has two modes, a reduction mode and an oxidation mode.- Iron-wuestite
- FeOIron(II) oxideIron oxide, also known as ferrous oxide, is one of the iron oxides. It is a black-colored powder with the chemical formula . It consists of the chemical element iron in the oxidation state of 2 bonded to oxygen. Its mineral form is known as wüstite. Iron oxide should not be confused with rust,...
+H2↔FeIronIron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
+H2O- Magnetite-wuestite
- Fe3O4MagnetiteMagnetite is a ferrimagnetic mineral with chemical formula Fe3O4, one of several iron oxides and a member of the spinel group. The chemical IUPAC name is iron oxide and the common chemical name is ferrous-ferric oxide. The formula for magnetite may also be written as FeO·Fe2O3, which is one part...
+H2↔3FeOWüstiteWüstite is a mineral form of iron oxide found with meteorites and native iron. It has a gray color with a greenish tint in reflected light. Wüstite crystallizes in the isometric - hexoctahedral crystal system in opaque to translucent metallic grains. It has a Mohs hardness of 5 to 5.5 and a...
+H2O
Application
The sponge iron reaction is used in the reformer sponge iron cycleReformer sponge iron cycle
The reformer sponge iron cycle is a two step cycle to produce hydrogen from hydrocarbon fuels based on the sponge iron reaction and steam.-Process description:...
in combination with a steam reforming
Steam reforming
Fossil fuel reforming is a method of producing hydrogen or other useful products from fossil fuels such as natural gas. This is achieved in a processing device called a reformer which reacts steam at high temperature with the fossil fuel. The steam methane reformer is widely used in industry to...
unit.