The syngas is exposed to particles of iron oxide–that is, rust–which act as an oxygen carrier. As it reacts with the syngas, the iron oxide releases its oxygen, forming metallic iron. The oxygen oxidizes the carbon monoxide, forming carbon dioxide, and the hydrogen, forming steam.

Does rusting release gas?

Iron combines with oxygen to form a mineral called hematite (Fe₂O₃). ... This means that iron will, albeit slowly, take the oxygen right out of water to become rust - producing hydrogen gas.

What chemicals does rust release?

Carbon dioxide and water react to form weak carbonic acid. Carbonic acid is a better electrolyte than pure water. As the acid attacks the iron, water breaks into hydrogen and oxygen. Free oxygen and dissolved iron form iron oxide, releasing electrons, which can flow to another part of the metal.