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Solar Metal Sulfate-Ammonia Based Thermochemical Water Splitting Cycle for Hydrogen Production

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Solar Metal Sulfate-Ammonia Based Thermochemical Water Splitting Cycle for Hydrogen Production University of Central Florida STARS UCF Patents Technology Transfer 4-8-2014 Solar metal sulfate-ammonia based thermochemical water splitting cycle for hydrogen production. Cunping Huang University of Central Florida Nazim Muradov University of Central Florida Ali Raissi University of Central Florida Find similar works at: https://stars.library.ucf.edu/patents University of Central Florida Libraries http://library.ucf.edu This Patent is brought to you for free and open access by the Technology Transfer at STARS. It has been accepted for inclusion in UCF Patents by an authorized administrator of STARS. For more information, please contact [email protected]. Recommended Citation Huang, Cunping; Muradov, Nazim; and Raissi, Ali, "Solar metal sulfate-ammonia based thermochemical water splitting cycle for hydrogen production." (2014). UCF Patents. 525. https://stars.library.ucf.edu/patents/525 I lllll llllllll Ill lllll lllll lllll lllll lllll 111111111111111111111111111111111 US008691068B 1 c12) United States Patent (10) Patent No.: US 8,691,068 Bl Huang et al. (45) Date of Patent: *Apr. 8, 2014 (54) SOLAR METAL SULFATE-AMMONIA BASED 3,882,222 A * 5/1975 Deschamps et al. .......... 423/575 THERMOCHEMICAL WATER SPLITTING (Continued) CYCLE FOR HYDROGEN PRODUCTION (75) Inventors: Cunping Huang, Cocoa, FL (US); Ali FOREIGN PATENT DOCUMENTS T-Raissi, Melbourne, FL (US); Nazim GB 1486140 * 9/1977 Muradov, Melbourne, FL (US) OTHER PUBLICATIONS (73) Assignee: University of Central Florida Research Foundation, Inc., Orlando, FL (US) Licht, Solar Water Splitting to Generate Hydrogen Fuel: Photothermal Electrochemical Analysis, Journal of Physical Chem­ ( *) Notice: Subject to any disclaimer, the term ofthis istry B, 2003, vol. 107, pp. 4253-4260.* patent is extended or adjusted under 35 U.S.C. 154(b) by 971 days. (Continued) This patent is subject to a terminal dis­ Primary Examiner - Harry D Wilkins, III claimer. (74) Attorney, Agent, or Firm - Brian S. Steinberger; (21) Appl. No.: 12/267,569 Phyllis K. Wood; Law Offices of Brian S. Steinberger, P.A. (22) Filed: Nov. 8, 2008 (57) ABSTRACT Two classes of hybrid/thermochemical water splitting pro­ Related U.S. Application Data cesses for the production of hydrogen and oxygen have been proposed based on (1) metal sulfate-ammonia cycles (2) (60) Provisional application No. 60/986,820, filed on Nov. metal pyrosulfate-ammonia cycles. Methods and systems for 9, 2007. a metal sulfate MS04 -NH3 cycle for producing H2 and 0 2 (51) Int. Cl. from a closed system including feeding an aqueous (NH3 ) 4 C25B 1102 (2006.01) S03 solution into a photoctalytic reactor to oxidize the aque­ COlC 11246 (2006.01) ous (NH3 ) 4 S03 into aqueous (NH3 ) 2 SO4 and reduce water to COJB 17150 (2006.01) hydrogen, mixing the resulting aqueous (NH3 ) 2 S04 with C25B 1100 (2006.01) metal oxide (e.g. ZnO) to form a slurry, heating the slurry of (52) U.S. Cl. aqueous (NH4 ) 2 S04 and ZnO(s) in the low temperature reac­ CPC . C25B 11003 (2013.01); C25B 1102 (2013.01); tor to produce a gaseous mixture ofNH3 and H2 0 and solid COJB 171504 (2013.01) ZnS04 (s ), heating solid ZnS04 at a high temperature reactor USPC ......... 205/340; 205/637; 423/541.4; 423/356 to produce a gaseous mixture ofS02 and 0 2 and solid product (58) Field of Classification Search ZnO, mixing the gaseous mixture ofS02 and 0 2 with an NH3 USPC .......................................................... 423/356 and H2 0 stream in an absorber to form aqueous (NH4 ) 2 S03 See application file for complete search history. solution and separate 0 2 for aqueous solution, recycling the resultant solution back to the photoreactor and sending ZnO (56) References Cited to mix with aqueous (NH4 ) 2 S04 solution to close the water splitting cycle wherein gaseous H and 0 are the only prod­ U.S. PATENT DOCUMENTS 2 2 ucts output from the closed ZnS04 -NH3 cycle. 3,243,261 A * 3/1966 Deiters ......................... 423/356 16 Claims, 9 Drawing Sheets H,o 65°c L_ H20+(NH..il2~:;{)'1 H,O = + 0 11,o+(Hlf..ihS03 US 8,691,068 Bl Page 2 (56) References Cited Fuel; Theory and Experiment for Efficient Solar Water Splitting, Int. J. of Hydrogen Energy, 2001, pp. 653-659, vol. 26. U.S. PATENT DOCUMENTS Deutsch, T.G., Koval, C.A., Turner, J.A., III-V Nitride Epilayers for Photoelectrochemical Water Splitting: GaPN and GaAsPN, J. Phys. 4,180,550 A * 12/1979 Deschamps et al. 423/244.1 Chem. B., 2006, pp. 25297-25307, vol. llO. 4,484,992 A * 1111984 Buhler et al. 204/157.52 Liu, H., Yuan, K., Shangguan, W., Photochemical Reduction and 7,220,391 Bl 5/2007 Huang et al. Oxidation ofWater Including Sacrificial Reagents and Pt/Ti02 Cata­ 7,332,146 Bl 2/2008 Huang et al. lyst, Energy and Fuels, 2006, pp. 2289-2292, vol. 20, No. 6. 2004/0234441 Al * 1112004 Hansen 423/356 T-Raissi, A., Muradov, N., Huang, C., Adebiyi, 0., Hydrogen from 2008/0289951 Al* 1112008 Huang et al. 204/157.52 Solar via Light-Assisted High-Temperature Water Splitting Cycles, OTHER PUBLICATIONS J. Solar Energy Engineering, 2007, pp. 184-189, vol. 129. Bilgen, E., Ducarroir, M., Foex, M., Sibieude, F., Trombe, F., Use of Imenes et al., Spectral beam splitting technology for increased con­ Solar Energy for Direct and Two-Step Water Decomposition Cycles, Int. J. Hydrogen Energy, 1977, pp. 251-257, vol. 2, No. 3. version efficiency in solar concentrating systems: a review, Solar Steinfeld, A., Solar Hydrogen Production via Two-Step Water Split­ Energy Materials & Solar Cells, 2004, vol. 84, pp. 19-69.* ting Thermochemical Cycle Based on Zn-ZnO Redox Reaction, Int. Dugger et al., Ammonium Sulfate Decomposition, United States J. Hydrogen Energy, 2002, pp. 611-619, vol. 27. Atomic Energy Commission, International Minerals and Chemical Abanades, S., Charvin, P., Flamant, G., Neveu, P., Screening of Corporation, Feb. 1955. * Water-Splitting Thermochemical Cycles Potentially Attractive for Wentworth, Thermochemical Cycles for Energy Storage: Thermal Hydrogen Production by Concentrated Solar Energy, Energy, 2006, Decomposition of ZnS04 Systems, Final Topcial Report, National pp. 2805-2822, vol. 31. Renewable Energy Laboratory, Apr. 1992. * Huang, C., T-Raissi, A., A Perspective on Thermodynamics and Raissi, "Analysis of Solar Thermochemical Water-Splitting Cycles Thermal Efficiency Calculations for Hydrogen Production via for Hydrogen Production", Hydrogen, Fuel Cells, and Infrastructure Thermochemical Water Splitting Cycles. Technologies, Dept. of Energy, FY 2003 Progress Report, Oct. 2003, Steinfeld, A., Solar Thermochemical Production of Hydrogen-A pp. II-159 to II-165.* Review, Solar Energy, 2005, pp. 603-615, vol. 78. Khaselev, 0., Turner, J.A., A Monolithic Photovoltaic­ Brecher, L.E., Spewock, S., et al., Westinghouse Sulfur Cycle forthe Photoelectrochemical Device for Hydrogen Production via Water Thermochemical Decomposition of Water, Proceedings of the 1st Splitting, Science, 1998, pp. 425-427, vol. 280, No. 5362. World Hydrogen Energy Conf., 1976, pp. 1-16, 1 9A. Licht, S., Wang, B., Mukerji, S., Soga, T., Umeno, M., Tributsch, H., Over 18% Solar Energy Conversion for Generation of Hydrogen * cited by examiner U.S. Patent Apr. 8, 2014 Sheet 1of9 US 8,691,068 Bl Direct Water Splitting TCWSPC (") I <I + N I <I + :f <I II 5: I <l Fig. 1 Water Fig. 2 U.S. Patent Apr. 8, 2014 Sheet 2of9 US 8,691,068 Bl Separation (~Hs) Water Circulation ( ~E) Fig. 3 ~ 00 Fig. 4 • ~ ~ Solar hv 1120 ~ ~ 25°c I Separator =~ l 1t HX H20 H20 2s 0 c 1 kmollh ~ 65°c :-: I L 1120+ (N~hS04 ~CIO ~~~~.~~~~~~~- H20 N 0.... .i;... HX H20+NH3 HX 02 1J1 ('D=­ ('D..... H20 (.H 0..... 65°c 0 2+S02 "° Oi+S02 12uo 0 c Oi+S02 + ZnO 1200°c d rJl. H20 00 H20+(NH4J2S03 H20+(NH4hS03 \C 0 2+S02 °""'"" 0--, =00 ="'"" U.S. Patent Apr. 8, 2014 Sheet 4of9 US 8,691,068 Bl U.S. Patent Apr. 8, 2014 Sheet 5of9 US 8,691,068 Bl U.S. Patent Apr. 8, 2014 Sheet 6of9 US 8,691,068 Bl U.S. Patent Apr. 8, 2014 Sheet 7of9 US 8,691,068 Bl U.S. Patent Apr. 8, 2014 Sheet 8of9 US 8,691,068 Bl U.S. Patent Apr. 8, 2014 Sheet 9of9 US 8,691,068 Bl US 8,691,068 Bl 1 2 SOLAR METAL SULFATE-AMMONIA BASED Khaselev and Turner reported that the hydrogen production THERMOCHEMICAL WATER SPLITTING efficiency of 12.4% for a monolithic photoelectrochemical­ CYCLE FOR HYDROGEN PRODUCTION photovoltaic device based on the short-circuit current and the lower heating value of hydrogen as described in Khaselev 0. CROSS REFERENCE TO RELATED 5 and Turner J. A., "A Monolithic Photovoltaic-Photoelectro­ APPLICATIONS chemical Device for Hydrogen Production via Water Split­ ting," Science, 280(17), pp. 425-7, 1998. The electrolyte used This application claims the benefit of priority to U.S. Pro­ by Khaselev and Turner was 3 M sulfuric acid aqueous solu­ visional Application No. 60/986,820 filed on Nov. 9, 2007, tion and the high cell output could only be maintained for less the entire disclosure of which is incorporated by reference in 10 than 34 minutes after which the efficiency began to drop its' entirety. precipitously. According to Licht, S., Wang, B., Mukerji, S., Soga, T., Umeno, M. and Tributsch, H., "Over 18% Solar GOVERNMENT LICENSE RIGHTS Energy Conversion for Generation of Hydrogen Fuel; Theory and Experiment for Efficient Solar Water Splitting," Int. J. of This invention was made with Govermnent support under 15 Hydrogen Energy, 26, pp. 653-659, 2001, Licht and co-work­ National Aeronautics and Space Administration(NASA) ers reported a solar to hydrogen energy conversion efficiency Glenn Research Center contract NAG3-2751 awarded by the of more than 18% using a multi-junction photoelectrode in National Aeronautics and SpaceAdministration(NASA).
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