New thermochemical cycles for hydrogen production

The ease of decomposing some metal sulfates to oxides and sulfur trioxide is employed in the search for efficient closed cycle thermochemical methods for water splitting. The main features of the new processes are the production of O₂ through the decomposition of SO₂ and/or SO₃, the production of hydrogen by the decomposition of H₂S, reaction of H₂S with a metal, reaction of water with a metal, and/or reaction of water with sulfides.