Cerium(IV) oxide–cerium(III) oxide cycle
The cerium(IV) oxide–cerium(III) oxide cycle or CeO2/Ce2O3 cycle is a two-step thermochemical process that employs cerium(IV) oxide and cerium(III) oxide for hydrogen production. The cerium-based cycle allows the separation of H2 and O2 in two steps, making high-temperature gas separation redundant.
For the first endothermic step, cerium(IV) oxide is thermally dissociated in an inert gas atmosphere at 2,000 °C (3,630 °F) and 100-200 mbar into cerium(III) oxide and oxygen. In the second exothermic step cerium(III) oxide reacts at 400 °C (752 °F)–600 °C (1,112 °F) in a fixed bed reactor with water and produces hydrogen and cerium(IV) oxide.
- Copper–chlorine cycle
- Hybrid sulfur cycle
- Iron oxide cycle
- Solar thermal energy
- Sulfur–iodine cycle
- Zinc–zinc oxide cycle