Thermochemical hydrogen production cycles

Pickard, P., Sulfur-iodine thermochemical cycle, 2006 Annual Merit Review Proc., Hydrogen Production and Delivery, D. Nuclear Energy Initiative, http //www.hydrogen.energy.gov/ annual review06 delivery.html. 

Nakajima, H. et al., A study on a closed-cycle hydrogen production by thermochemical watersplitting IS process, ICONE-7104, in Proc. 7th Int. Conf. Nucl. Eng., Tokyo, Japan, April 19-23,... 

High temperature nuclear thermochemical cycles, hydrogen production by, 13 847-849... 

Thermochemical cycles based on solar energy are another long-term option for hydrogen production in countries with favourable climatic conditions. 

The sulfur-iodine thermochemical water-splitting cycle (S-1 cycle) developed for hydrogen production from water is fundamentally based on the following three chemical reactions (Wang, 2007) ... 

Huang, C., Raissi, T.-A. 2005. Analysis of sulfur-iodine thermochemical cycle for solar hydrogen production. Part I decomposition of sulfuric acid. Solar Energy 78 632-646. 

Abanades S, Charvin P, Flamant G, Neveu P (2006) Screening of water-splitting thermochemical cycles potentially attractive for hydrogen production by concentrated solar energy. Energy 31 2805-2822... 

Sakurai M, Bilgen E, Tsutsumi A, Yoshida K (1996) Solar UT-3 thermochemical cycle for hydrogen production. Sol Energy 57 51-58... 

In situ formation and hydrolysis of Zn nanoparticles for H2 production by the 2-step ZnO/Zn water-splitting thermochemical cycle. Int J Hydrogen Energy 31 55-61... 

Steinfeld A (2002) Solar hydrogen production via a two-step water-splitting thermochemical cycle based on Zn/ZnO redox reactions. Int J Hydrogen Energy 27 611-619... 

Kubo S, Nakajima, Kasahara HS, Higashi S, Masaki T, Abe H, Onuki (2004) A demonstration study on a closed-cycle hydrogen production by the thermochemical water-splitting iodine-sulfur process. Nucl Eng Des 233 347-354... 

Deneuve E, Roncato JP (1981) Thermochemical or hybrid cycles of hydrogen production- technolo-echonomical comparison with water electrolysis. Int J Hydrogen Energy 6 9-23... 

Mathias, P. M., Brown, L. C., Thermodynamics of the sulfur-iodine cycle for thermochemical hydrogen production, in Proceedings of the 68th Annual Meeting Of the Society of Chemical Engineers (23 March 2003), Japan, 2003. 

Session 4 focused on recent advances in the thermochemical copper chloride and calcium bromide cycles. Much of the current research on thermochemical cycles for hydrogen production involves the sulphur cycles (sulphur-iodine, hybrid sulphur), however, these cycles require very high temperatures ( 800-900°C) to drive the acid decomposition step. The interest in the Cu-Cl and Ca-Br cycles is due to the lower peak temperature requirements of these cycles. The peak temperature requirement for the Cu-Cl cycle is about 550°C, which would allow this cycle to be used with lower temperature reactors, such as sodium- or lead-cooled reactors, or possibly supercritical water reactors. Ca-Br requires peak temperatures of about 760°C. Both of these cycles are projected to have good efficiencies, in the range of 40%. Work on Cu-Cl is ongoing in France, Canada and the United States. Work on Ca-Br has been done primarily in Japan and the US, with the more recent work being done in the US at ANL. The papers presented in this session summarised the recent advances in these cycles. 

Kubo, S., et al. (2004), A Demonstration Study on a Closed-cycle Hydrogen Production by Thermochemical Water-splitting Iodine-Sulfur Process , Nitcl. Eng. Des., 233, 347-354. 

The target cost of nuclear hydrogen production must be cheaper than that of the conventional electrolysis subtracting the distribution cost. Hydrogen production efficiency of EED-aided SI thermochemical cycle is expected around 43% with current knowledge (Cho, 2009). 

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