Hydrogen sulfur-iodine cycle

Knoche, K.F. et al, Second law and cost analysis of the oxygen generation step of the general atomic sulfur-iodine cycle, in Proc. 5th World Hydrogen Energy Conf, Toronto, 2, 487, July, 1984. 

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. 

Hadj-Kali, M.K., et al. (2009a), HIX System Thermodynamic Model for Hydrogen Production by the Sulfur-iodine Cycle , Int. J. Hydrogen Energy, 34,1696-1709. 

Buckingham, R., et al. (Buckingham, 2008), Modeling the Sulfur-Iodine Cycle A Comparison of Techniques , World Hydrogen Energy Conference, Brisbane, Australia, June. 

Mathias, Paul M., Lloyd C. Brown, et al. (2003), Thermodynamics of the Sulfur-Iodine Cycle for Thermochemical Hydrogen Production , 68th Annual Meeting of the Society of Chemical Engineers, Japan, 23 March. 

The information exchange meeting participants strongly endorsed further international cooperation on issues related to nuclear hydrogen production. Extensive collaboration already exists in some research areas, including the sulfur-iodine cycle. Additional areas of cooperation could include ... 

However, until the study for CSP is complete and performance and cost estimates for commercial plants developed, the best available information about thermochemical hydrogen production comes from the nuclear studies. Consequently, the basis for the CSP inputs used in this model is the same as for the nuclear thermochemical case - based on the sulfur-iodine cycle cost and performance information from Schultz (2003). 

Thermochemical cycles are a solution to this problem as they split water using special catalysts and heat As an example, the sulfur-iodine-cycle will briefly be discussed. When heat is added, the sulfuric acid is split into sulfur dioxide, water and oxygen. In a second step, heat is added again to produce hydrogen iodide and... 

Liberatore et al. [11] detail the state of the art for a thermochemical cycle producing hydrogen on the basis of the sulfur-iodine cycle using a planning calculation for a plant with a productirai rate of 100 t/day. As a source of heat and power, a combination of parabolic thermal collectors and heliostats with a central receiver is used. An economic viability analysis resulted in hydrogen costs of 8.30 /kg. 

The sulfur-iodine cycle is a series of thermo-chemical processes used to obtain hydrogen. It consists of three chemical reactions whose net reactant is water and whose net products are hydrogen and oxygen. 

The sulfur-iodine cycle has been proposed as a way to supply hydrogen for a hydrogen-based economy. It does not require hydrocarbons like current methods of steam reforming. 

The sulfur-iodine cycle is currently being researched as a feasible method of obtaining hydrogen, but the concentrated, corrosive acid at high temperatures poses currently insurmountable safety hazards if the process were built on a large scale. 

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. 

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. 

Norman JH, Mysels KJ, Sharp R, Williamson D (1982) Studies of the sulfur-iodine thermochemical water-splitting cycle. Int J Hydrogen Energy 7 545-556... 

Brown, L.C., R.D. Lentsch, G.E. Besenbruch, K.R. Schultz (2003), Alternative Flowsheets for the Sulfur-Iodine Thermochemical Hydrogen Cycle , AIChE Journal, April. 

Vitart, X., P. Carles, P. Anzieu (2008), A General Survey of the Potential and the Main Issues Associated with the Sulfur-Iodine Thermochemical Cycle for Hydrogen Production Using Nuclear Heat , Nuclear... 

Pickard, P. (2008), Sulfur-iodine Thermochemical Cycle , 2008 DOE Hydrogen Program Review. 

The sulfur-iodine thermo chemical water-splitting cycle continues to represent a promising approach to the production of hydrogen utilizing an entirely thermal energy source. Another significant step toward its viability has been taken by the successful closure of the cycle in this laboratory demonstration. 

Norman, J. H. Mysels, K. J. O Keefe, D. R. Stowell, S. A. Williamson, D. G., "Chemical Studies on the General Atomic Sulfur-Iodine Thermochemical Water-Splitting Cycle," paper presented at the Second World Hydrogen Energy Conference, Zurich, Switzerland, August 1978. 

A recent screening of several hundred possible reactions (Besenbruch et al 2001) has identified two candidate thermochemical cycles for hydrogen production from water (i.e., cycles that enable chemical reactions to take place at high temperatures) with high potential for efficiency and practical applicability to nuclear heat sources. These are the sulfur-iodine (S-I) and calcium-bromine-iron (Ca-Br) cycles. Also, Argonne National Laboratory (ANL) has identified the copper-chlorine (Cu-Cl) thermochemical cycle for this purpose (Doctor et al 2002). A hybrid sulfur-based process that does not require iodine but has a single electrochemical... 

D. OKeefe, C. Allen, G. Besenbruch, L. Brown, J. Norman, R. Sharp, and K. McCorkle, Preliminary results from bench-scale testing of sulfur-iodine thermochemical watersplitting cycle, Int. J. Hydrogen Energy, 7 381-392 (1982). 

The sulfur-iodine (S-I) cycle is a thermochemical water-splitting process that utilizes thermal energy from a high-temperature heat source to produce hydrogen (H2). It is comprised of three coupled chemical reactions, as shown in figure 4.1. First, the central low-temperature Bunsen reaction (Section I) is employed to produce two... 

Commercial success of sulfur-iodine hydrogen production depends largely on the capacity to identify materials of construction that can handle the corrosive environments and on the ability to manufacture process components with these materials economically. This chapter has reviewed a cross-section of materials data generated by testing in the various process settings within the cycle. Ta alloys and SiC have been shown to have good corrosion characteristics in all the liquid environments, but individual candidates have also been suggested for use in particular conditions. Both of these materials have unique mechanical properties, and much effort is needed in order to use them for component fabrication. 

Huang, C., and T-Raissi, A., Analysis of Sulfur-Iodine Thermochemical Cycle for Solar Hydrogen Production. Part I - Decomposition of Sulfuric Acid, Solar Energy, 78(5), 632-46,2005. 

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