Updated on 2025/10/26
博士(理学) ( 1994.3 東京工業大学 )
Inorganic Material
太陽熱化学
Catalyst
触媒
無機材料
水素エネルギー
資源利用化学
Energy Science
Nanotechnology/Materials / Energy chemistry
Nanotechnology/Materials / Functional solid state chemistry
Nanotechnology/Materials / Inorganic compounds and inorganic materials chemistry
Niigata University Faculty of Engineering, Department of Engineering, Chemistry & Chemical Engineering Program Professor
2003.4
Country：Japan
Niigata University Faculty of Engineering, Department of Chemistry and Chemical Engineering Associate Professor
1997 - 2003
Country：Japan
Niigata University Faculty of Engineering, Department of Chemistry and Chemical Engineering Research Associate
1995.4 - 1997.3
Country：Japan
Post doctoral Fellows, Japan Society for the Promotion of Science
1992.4 - 1995.3
Niigata University Faculty of Engineering Department of Engineering Professor
2017.4
Niigata University Graduate School of Science and Technology Advanced Materials Science and Technology Professor
2004.4
Niigata University Graduate School of Science and Technology Advanced Materials Science and Technology Professor
2004.4
Niigata University Faculty of Engineering Department of Chemistry and Chemical Engineering Professor
2003.4 - 2017.3
Niigata University Faculty of Engineering Associate Professor (as old post name)
1997.4 - 2003.3
Niigata University Faculty of Engineering Research Assistant
1995.4 - 1997.3
Tokyo Institute of Technology Science of Engineering 化学専攻
1992.4 - 1994.3
Tokyo Institute of Technology Graduate School of Science and Engineering 化学専攻
1990.4 - 1992.3
Country： Japan
Tokyo Institute of Technology School of Science 化学科
1986.4 - 1990.3
Country： Japan
日本太陽エネルギー学会
日本エネルギー学会
日本エネルギー学会 理事
2003
日本太陽エネルギー学会 太陽熱部会 幹事
Takaki Nishimura, Tatsuya Kodama, Sakane Genta, Tomohiko Ishii
Scientific Reports 12 ( 1 ) 2022.6
Selvan BELLAN, Tatsuya KODAMA, Hyun SEOK CHO, Jin-Soo KIM
Journal of Thermal Science and Technology 17 ( 2 ) 22 - 00076 2022
Hyun-Seok Cho, Tatsuya Kodama, Nobuyuki Gokon, Selvan Bellan, Jong-Kyu Kim
Energies 14 ( 21 ) 6919 - 6919 2021.10
Heat transfer and particulate flow analysis of a 30 kW directly irradiated solar fluidized bed reactor for thermochemical cycling Reviewed
Selvan Bellan, Tatsuya Kodama, Koji Matsubara, Nobuyuki Gokon, Hyun Seok Cho, Kousuke Inoue
Chemical Engineering Science 203 511 - 525 2019.8
Tatsuya Kodama, Hyun Seok Cho, Kouske Inoue, Tatsuya Saito, Shouta Watanabe, Nobuyuki Gokon, Selvan Bellan
AIP Conference Proceedings 2126 180011 2019
Heat transfer analysis of 5kW<inf>th</inf> circulating fluidized bed reactor for solar gasification using concentrated Xe light radiation Reviewed
Selvan Bellan, Nobuyuki Gokon, Koji Matsubara, Hyun Seok Cho, Tatsuya Kodama
Energy 160 245 - 256 2018.10
Particle reactors for solar thermochemical processes Reviewed
Tatsuya Kodama, Selvan Bellan, Nobuyuki Gokon, Hyun Seok Cho
SOLAR ENERGY 156 113 - 132 2017.11
Thermochemical reactivity of 5-15 mol% Fe, Co, Ni, Mn-doped cerium oxides in two-step water-splitting cycle for solar hydrogen production Reviewed
Nobuyuki Gokon, Toshinori Suda, Tatsuya Kodama
THERMOCHIMICA ACTA 617 ( 10 ) 179 - 190 2015.10
Simulation of Flux Distributions on the Foam Absorber with Solar Reactor for Thermo-chemical Two-step Water Splitting H2 Production Cycle by the 45 kWth KIER Solar Furnace Reviewed
H.S. Cho, N. Gokon, T. Kodama, Y.H. Kang, J.K. Kim
Energy Procedia 69 790 - 801 2015.5
Improved operation of solar reactor for two-step water-splitting H 2 production by ceria-coated ceramic foam device Reviewed
H.S. Cho, N. Gokon, T. Kodama, Y.H. Kang, H.J. Lee
International Journal of Hydrogen Energy 40 ( 1 ) 114 - 124 2015.1
Thermochemical two-step water splitting by internally circulating fluidized bed of NiFe2O4 particles: Successive reaction of thermal-reduction and water-decomposition steps Reviewed
Nobuyuki Gokon, Tetsuro Mataga, Nobuyuki Kondo, Tatsuya Kodama
International Journal of Hydrogen Energy 36 ( 8 ) 4757 - 4767 2011.4
Ferrite/zirconia-coated foam device prepared by spin coating for solar demonstration of thermochemical water-splitting Reviewed
Nobuyuki Gokon, Tatsuya Kodama, Nobuki Imaizumi, Jun Umeda, Taebeom Seo
International Journal of Hydrogen Energy 36 ( 3 ) 2014 - 2028 2011.2
Comparative study of the activity of nickel ferrites for solar hydrogen production by two-step thermochemical cycles Reviewed
Fernando Fresno, Tomoaki Yoshida, Nobuyuki Gokon, Rocío Fernández-Saavedra, Tatsuya Kodama
International Journal of Hydrogen Energy 35 ( 16 ) 8503 - 8510 2010.8
A reactive Fe-YSZ coated foam device for solar two-step water splitting Reviewed
Tatsuya Kodama, Tomoki Hasegawa, Ayumi Nagasaki, Nobuyuki Gokon
Journal of Solar Energy Engineering, Transactions of the ASME 131 ( 2 ) 0210081 - 0210087 2009.5
Application of an internally circulating fluidized bed for windowed solar chemical reactor with direct irradiation of reacting particles Reviewed
Tatsuya Kodama, Syu-Ichi Enomoto, Tsuyoshi Hatamachi, Nobuyuki Gokon
Journal of Solar Energy Engineering, Transactions of the ASME 130 ( 1 ) 0145041 - 0145044 2008.2
Thermochernical cycles for high-temperature solar hydrogen production Reviewed
Tatsuya Kodama, Nobuyuki Gokon
CHEMICAL REVIEWS 107 ( 10 ) 4048 - 4077 2007.10
Ru/Ni-Mg-O catalyzed SiC-foam absorber for solar reforming receiver-reactor Reviewed
Tatsuya Kodama, Takuya Moriyama, Takehiro Shimoyama, Nobuyuki Gokon, Hidemasa Andou, Nobuhiro Satou
JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME 128 ( 3 ) 318 - 325 2006.8
Thermochemical hydrogen production by a redox system of ZrO2-supported Co(II)-ferrite Reviewed
T Kodama, Y Kondoh, R Yamamoto, H Andou, N Satou
SOLAR ENERGY 78 ( 5 ) 623 - 631 2005
Catalytically activated metal foam absorber for light-to-chemical energy conversion via solar reforming of methane
T Kodama, A Kiyama, KI Shimizu
ENERGY & FUELS 17 ( 1 ) 13 - 17 2003.1
Two-step carbon dioxide thermochemical splitting using foam device of ceria and hercynite Reviewed
Y. Koyama, K, Ito, S. Ohta, M. Nakakura, T. Kodama, K. J. Warren, A. W. Weimer, K. Matsubara
Journal of Japan Solar Energy Society 49 ( 4 ) 71 - 76 2023
A review on high‐temperature thermochemical heat storage: Particle reactors and materials based on solid–gas reactions Invited Reviewed
Selvan Bellan, Tatsuya Kodama, Nobuyuki Gokon, Koji Matsubara
WIREs Energy and Environment 11 ( 5 ) 2022.5
Theoretical research aiming at high-efficiency hydrogen production using solar thermochemical energy for the goal of sustainable energy supply Reviewed
Nishimura, T, Kodama, T, Sakane, G, Ishii T
Journal of Kagawa University International Office 14 253 - 259 2022
Genta TSURUMAKI, Selvan BELLAN, Koji MATSUBARA, Tatsuya KODAMA, Mitsuho NAKAKURA, Nobuyuki GOKON, Hyun SEOK CHO, Karthik MANI, Sakthivel SHANMUGASUNDARAM
Journal of Thermal Science and Technology 17 ( 2 ) 22 - 00061 2022
Phase Change Material of Copper–Germanium Alloy as Solar Latent Heat Storage at High Temperatures Reviewed
Nobuyuki Gokon, Chew Shun Jie, Yuya Nakano, Shogo Okazaki, Tatsuya Kodama, Tsuyoshi Hatamachi, Selvan Bellan
Frontiers in Energy Research 9 2021.6
Experimental Study of Mn-CeO<inf>2</inf> Coated Ceramic Foam Device for Two-step Water Splitting Cycle Hydrogen Production with 3kW Sun-simulator Reviewed
Hyun Seok Cho, Tatsuya Kodama, Nobuyuki Gokon, Selvan Bellan, Naoyoshi Nishigata
AIP Conference Proceedings 2303 2020.12
Chemical compatibility of Cu-Ge alloy with container materials for latent heat storage system Reviewed
Nobuyuki Gokon, Chew Shun Jie, Selvan Bellan, Tatsuya Kodama, Tsuyoshi Hatamachi, Hyunseok Cho
AIP Conference Proceedings 2303 2020.12
Thermochemical two-step CO<inf>2</inf> splitting using La<inf>0.7</inf>Sr<inf>0.3</inf>Mn<inf>0.9</inf>Cr<inf>0.1</inf>O<inf>3</inf> of perovskite oxide for solar fuel production Reviewed
Hiroki Sawaguri, Nobuyuki Gokon, Naoki Ito, Selvan Bellan, Tatsuya Kodama, Hyun Seok Cho
AIP Conference Proceedings 2303 2020.12
Thermochemical H<inf>2</inf>O splitting using LaSrMnCrO<inf>3</inf> of perovskite oxides for solar hydrogen production Reviewed
Nobuyuki Gokon, Kazuki Hara, Naoki Ito, Hiroki Sawaguri, Selvan Bellan, Tatsuya Kodama, Hyun Seok Cho
AIP Conference Proceedings 2303 2020.12
Numerical analysis on solidification process of PCM in triplex-tube thermal energy storage system
Koya Hirai, Selvan Bellan, Koji Matsubara, Tatsuya Kodama, Nobuyuki Gokon, Hyun Seok Cho
AIP Conference Proceedings 2303 2020.12
Thermal charge/discharge performance of iron–germanium alloys as phase change materials for solar latent heat storage at high temperatures Reviewed
Nobuyuki Gokon, Chew Shun Jie, Yuya Nakano, Tatsuya Kodama, Selvan Bellan, Hyunseok Cho
Journal of Energy Storage 30 101420 - 101420 2020.8
Direct simulation of a volumetric solar receiver with different cell sizes at high outlet temperatures (1,000–1,500 °C) Reviewed
Mitsuho Nakakura, Koji Matsubara, Selvan Bellan, Tatsuya Kodama
Renewable Energy 146 1143 - 1152 2020.2
Thermochemical two-step water splitting cycle using perovskite oxides based on LaSrMnO3 redox system for solar H2 production
Nobuyuki Gokon, Kazuki Hara, Yuta Sugiyama, Selvan Bellan, Tatsuya Kodama, Cho Hyun-seok
Thermochimica Acta 680 2019.10
Direct Simulation of Volumetric Solar Receiver with Highly Concentrated Radiation
Mitsuho Nakakura, Koji Matsubara, Selvan Bellan, Tatsuya Kodama
IOP Conference Series: Materials Science and Engineering 556 ( 1 ) 2019.8
Fe-doped manganese oxide redox material for thermochemical energy storage at high-temperatures Reviewed
Nobuyuki Gokon, Aoi Nishizawa, Takehiro Yawata, Selvan Bellan, Tatsuya Kodama, Hyun Seok Cho
AIP Conference Proceedings 2126 2019.7
Efficiency and heat loss analysis of honeycomb receiver varying air mass flow rate and beam width Reviewed
Mitsuho Nakakura, Koji Matsubara, Selvan Bellan, Tatsuya Kodama
International Journal of Heat and Mass Transfer 137 1027 - 1040 2019.7
Thermochemical behavior of perovskite oxides based on La<inf>x</inf>Sr<inf>1-x</inf>(Mn, Fe, Co)O<inf>3-Δ</inf> and Ba<inf>y</inf>Sr<inf>1-y</inf>CoO<inf>3-Δ</inf> redox system for thermochemical energy storage at high temperatures Reviewed
Nobuyuki Gokon, Takehiro Yawata, Selvan Bellan, Tatsuya Kodama, Hyun Seok Cho
Energy 171 971 - 980 2019.3
Thermal performance of a 30 kW fluidized bed reactor for solar gasification: A CFD-DEM study Reviewed
Selvan Bellan, Tatsuya Kodama, Koji Matsubara, Nobuyuki Gokon, Hyun Seok Cho, Kousuke Inoue
Chemical Engineering Journal 360 1287 - 1300 2019.3
Development of a 5kW<inf>th</inf> internally circulating fluidized bed reactor containing quartz sand for continuously-fed coal-coke gasification and a beam-down solar concentrating system Reviewed
Nobuyuki Gokon, Satoshi Kumaki, Yosuke Miyaguchi, Selvan Bellan, Tatsuya Kodama, Hyunseok Cho
Energy 166 1 - 16 2019.1
Heat transfer and fluid flow analysis of a fluidized bed reactor for beam-down optics Reviewed
Selvan Bellan, Tatsuya Kodama, Koji Matsubara, Nobuyuki Gokon, Hyun Seok Cho
AIP Conference Proceedings 2126 180004 2019
Preliminary tests of batch type fluidized bed reactor for development of continuously-feeding fluidized bed reactor - An elevated temperature and gasification processes Reviewed
Nobuyuki Gokon, Shinpei Takagi, Selvan Bellan, Hyun Seok Cho, Tatsuya Kodama
AIP Conference Proceedings 2033 2018.11
Particle fluidized bed receiver/reactor with a beam-down solar concentrating optics: Performance test of two-step water splitting with ceria particles using 30-kWth sun-simulator
Tatsuya Kodama, Nobuyuki Gokon, Hyun Seok Cho, Selvan Bellan, Koji Matsubara, Kousuke Inoue
AIP Conference Proceedings 2033 2018.11
CFD-DEM investigation on flow and temperature distribution of ceria particles in a beam-down fluidized bed reactor
Selvan Bellan, Koji Matsubara, Hyun Seok Cho, Nobuyuki Gokon, Tatsuya Kodama
AIP Conference Proceedings 2033 2018.11
Numerical and experimental study on granular flow and heat transfer characteristics of directly-irradiated fluidized bed reactor for solar gasification Reviewed
Selvan Bellan, Nobuyuki Gokon, Koji Matsubara, Hyun Seok Cho, Tatsuya Kodama
International journal of hydrogen energy 43 ( 34 ) 1 - 15 2018.8
Conjugate radiation-convection-conduction simulation of volumetric solar receivers with cut-back inlets Reviewed
Mitsuho Nakakura, Selvan Bellan, Koji Matsubara, Tatsuya Kodama
Solar Energy 170 606 - 617 2018.8
A CFD-DEM study of hydrodynamics with heat transfer in a gas-solid fluidized bed reactor for solar thermal applications Reviewed
Selvan Bellan, Koji Matsubara, Hyun Seok Cho, Nobuyuki Gokon, Tatsuya Kodama
International Journal of Heat and Mass Transfer 116 377 - 392 2018.1
Gas-solid flow and heat transfer characteristics of a fluidized bed reactor for solar thermal applications
Selvan Bellan, Koji Matsubara, Nobuyuki Gokon, Tatsuya Kodama, Hyun Seok Cho, Issei Tsuchida
International Heat Transfer Conference 2018- 6519 - 6527 2018
Conjugated radiation-convection-conduction heat transfer analysis of volumetric receiver with highly concentrated radiation
Mitsuho Nakakura, Selvan Bellan, Hyun-Seok Cho, Koji Matsubara, Nobuyuki Gokon, Tatsuya Kodama
International Heat Transfer Conference 2018- 7866 - 7873 2018
Buoyancy-opposed volumetric solar receiver with beam-down optics irradiation Reviewed
Mitsuho Nakakura, Koji Matsubara, Hyun-Seok Cho, Tatsuya Kodama, Nobuyuki Gokon, Selvan Bellan, Kazuo Yoshida
Energy 141 2337 - 2350 2017.12
CFD-DEM investigation of particles circulation pattern of two-tower fluidized bed reactor for beam-down solar concentrating system Reviewed
Selvan Bellan, Koji Matsubara, Cho Hyun Cheok, Nobuyuki Gokon, Tatsuya Kodama
POWDER TECHNOLOGY 319 228 - 237 2017.9
Thermal Storage/Discharge Performances of Cu-Si Alloy for Solar Thermochemical Process Reviewed
Nobuyuki Gokon, Tomoya Yamaguchi, Hyun-seok Cho, Selvan Bellan, Tsuyoshi Hatamachi, Tatsuya Kodama
INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS (SOLARPACES 2016) 1850 2017
Development and Experimental Study for Hydrogen Production from the Thermochemical Two-step Water Splitting Cycles with a CeO2 Coated New Foam Device Design Using Solar Furnace System Reviewed
Hyun Seok Cho, Tatsuya Kodama, Nobuyuki Gokon, Jong Kyu Kim, Sang Nam Lee, Yong Heack Kang
AIP Conf. Proc. 1850 100003 2017
Particles Fluidized Bed Receiver/Reactor Tests with Quartz Sand Particles Using a 100-kW(th) Beam-Down Solar Concentrating System at Miyazaki Reviewed
Tatsuya Kodama, Nobuyuki Gokon, Hyun Seok Cho, Koji Matsubara, Hiroshi Kaneko, Kazuya Senuma, Sumie Itoh, Shin-nosuke Yokota
INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS (SOLARPACES 2016) 1850 2017
Numerical Analysis of Fluid Flow and Heat Transfer During Melting Inside a Cylindrical Container for Thermal Energy Storage System Reviewed
Selvan Bellan, Cho Hyun Cheok, Nobuyuki Gokon, Koji Matsubara, Tatsuya Kodama
INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS (SOLARPACES 2016) 1850 2017
Cyclic thermal storage/discharge performances of a hypereutectic Cu-Si alloy under vacuum for solar thermochemical process Reviewed
Nobuyuki Gokon, Tomoya Yamaguchi, Tatsuya Kodama
ENERGY 113 1099 - 1108 2016.10
Cold Test with a Benchtop Set-up for Fluidized Bed Reactor Using Quartz Sand to Simulate Gasification of Coal Cokes by Concentrated Solar Radiation Reviewed
Nobuyuki Gokon, Tomoaki Tanabe, Tadaaki Shimizu, Tatsuya Kodama
SOLARPACES 2015: INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS 1734 2016
Particles Fluidized Bed Receiver/Reactor with a Beam-Down Solar Concentrating Optics: 30-kW(th) Performance Test Using a Big Sun-Simulator Reviewed
Tatsuya Kodama, Nobuyuki Gokon, Hyun Seok Cho, Koji Matsubara, Tetsuro Etori, Akane Takeuchi, Shin-nosuke Yokota, Sumie Ito
SOLARPACES 2015: INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS 1734 2016
Oxygen and hydrogen productivities and repeatable reactivity of 30-mol%-Fe-, Co-, Ni-, Mn-doped CeO2-delta for thermochemical two-step water-splitting cycle Reviewed
Nobuyuld Gokon, Toshinori Suda, Tatsuya Kodama
ENERGY 90 1280 - 1289 2015.10
Steam gasification of coal cokes by internally circulating fluidized-bed reactor by concentrated Xe-light radiation for solar syngas production Reviewed
Nobuyuki Gokon, Takuya Izawa, Tatsuya Kodama
ENERGY 79 264 - 272 2015.1
Redox and fluidization performances of Co3O4/CoO for solar Thermochemical energy storage Reviewed
N. Gokon, S. Yokota, H. S. Cho, T. Hatamachi, T. Kodama
ISES Solar World Congress 2015, Conference Proceedings 806 - 815 2015
Laboratory experiment and simulation of higherature fluidized bed air receiver for concentrated solar power generation Reviewed
Koji Matsubara, Yuki Kazuma, Atsushi Sakurai, Tatsuya Kodama, Nobuyuki Gokon, Hyun-Seok Cho, Kazuo Yoshida, Yoshinori Nagase
Nihon Enerugi Gakkaishi/Journal of the Japan Institute of Energy 94 ( 11 ) 1323 - 1329 2015
Cold testings of a windowed fluidized bed reactor using quartz sand for solar gasification of coke Reviewed
N. Gokon, T. Tanabe, H. S. Cho, T. Hatamachi, T. Kodama
ISES Solar World Congress 2015, Conference Proceedings 799 - 805 2015
Steam gasification of coal cokes in an internally circulating fluidized bed of thermal storage material for solar thermochemical processes Reviewed
Nobuyuki Gokon, Takuya Izawa, Takehiko Abe, Tatsuya Kodama
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 39 ( 21 ) 11082 - 11093 2014.7
Steam reforming of methane using double-walled reformer tubes containing high-temperature thermal storage Na2CO3/MgO composites for solar fuel production Reviewed
Nobuyuki Gokon, Shohei Nakamura, Tsuyoshi Hatamachi, Tatsuya Kodama
ENERGY 68 773 - 782 2014.4
Carbonate molten-salt absorber/reformer: heating and steam reforming performance of reactor tubes Reviewed
N. Gokon, S. Nakamura, K. Matsubara, T. Kodama
PROCEEDINGS OF THE SOLARPACES 2013 INTERNATIONAL CONFERENCE 49 1940 - 1949 2014
Kinetics of thermal reduction step of thermochemical two-step water splitting using CeO2 particles: Master-plot method for analyzing non-isothermal experiments Reviewed
T. Ishida, N. Gokon, T. Hatamachi, T. Kodama
PROCEEDINGS OF THE SOLARPACES 2013 INTERNATIONAL CONFERENCE 49 1970 - 1979 2014
Solar demonstration of thermochemical two-step water splitting cycle using CeO2/MPSZ ceramic foam device by 45kW(th) KIER solar furnace Reviewed
H. S. Cho, T. Myojin, S. Kawakami, N. Gokon, T. Kodama, Y. H. Kang, S. N. Lee, K. K. Chai, H. K. Yoon, H. J. Lee
PROCEEDINGS OF THE SOLARPACES 2013 INTERNATIONAL CONFERENCE 49 1922 - 1931 2014
Thermochemical two-step water splitting cycle using Ni-ferrite and CeO2 coated ceramic foam devices by concentrated Xe-light radiation Reviewed
S. Kawakami, T. Myojin, H. -S. Cho, T. Hatamachi, N. Gokon, T. Kodama
PROCEEDINGS OF THE SOLARPACES 2013 INTERNATIONAL CONFERENCE 49 1980 - 1989 2014
Comparative study of activity of cerium oxide at thermal reduction temperatures of 1300-1550 degrees C for solar thermochemical two-step water-splitting cycle Reviewed
Nobuyuki Gokon, Sachi Sagawa, Tatsuya Kodama
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 38 ( 34 ) 14402 - 14414 2013.11
Oxygen-releasing step of nickel ferrite based on Rietveld analysis for thermochemical two-step water-splitting Reviewed
Nobuyuki Gokon, Ken Kondo, Tsuyoshi Hatamachi, Mineo Sato, Tatsuya Kodama
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 38 ( 12 ) 4935 - 4944 2013.4
CO 2 gasification of coal cokes using internally circulating fluidized bed reactor by concentrated Xe-light irradiation for solar gasification Reviewed
Nobuyuki Gokon, Ryuta Ono, Tsuyoshi Hatamachi, Li Liuyun, Hee-Joon Kim, Tatsuya Kodama
International Journal of Hydrogen Energy 37 ( 17 ) 12128 - 12137 2012.9
4-5-2 Studies of Na2CO3/MgO molten salt solar receiver reactor tube
TAKAHASHI Shogo, KURITA Shinji, HATAMACHI Tsuyoshi, SAKURAI Atsushi, GOKON Nobuyuki, KODAMA Tatsuya
Proceedings of the Annual Conference of The Japan Institute of Energy 21 232 - 233 2012
Kinetics of methane reforming over Ru/γ-Al2O 3-catalyzed metallic foam at 650-900 °c for solar receiver-absorbers Reviewed
Nobuyuki Gokon, Yuhei Yamawaki, Daisuke Nakazawa, Tatsuya Kodama
International Journal of Hydrogen Energy 36 ( 1 ) 203 - 215 2011.1
Comparison Studies of reactivity on nickel-ferrite and cerium-oxide redox materials for two-step thermochemical water splitting below 1400?C Reviewed
Tatsuya Kodama, Nobuki Imaizumi, Nobuyuki Gokon, Tsuyoshi Hatamachi, Daiki Aoyagi, Ken Kondo
2011 Energy Sustainability Conference & Fuel Cell Conference, Washington DC, USA, August 7-10, 2011. 2011
Ni/MgO-Al2O3 and Ni-Mg-O catalyzed SiC foam absorbers for high temperature solar reforming of methane Reviewed
Nobuyuki Gokon, Yuhei Yamawaki, Daisuke Nakazawa, Tatsuya Kodama
International Journal of Hydrogen Energy 35 ( 14 ) 7441 - 7453 2010.7
Internally circulating fluidized bed reactor using m-ZrO2 supported NiFe2O4 particles for thermochemical two-step water splitting Reviewed
Nobuyuki Gokon, Hiroki Yamamoto, Nobuyuki Kondo, Tatsuya Kodama
Journal of Solar Energy Engineering, Transactions of the ASME 132 ( 2 ) 0211021 - 02110210 2010.5
Molten-salt tubular absorber/reformer (MoSTAR) project: Reforming performance of reactor tubes during intermittent heating Reviewed
Nobuyuki Gokon, Tatsuya Kodama, Tsuyoshi Hatamachi, Shingo Yamashita, Taebeom Seo
ASME 2010 4th International Conference on Energy Sustainability, ES 2010 2 105 - 113 2010
Coal coke gasification in a windowed solar chemical reactor for beam-down optics Reviewed
Tatsuya Kodama, Nobuyuki Gokon, Shu-Ich Enomoto, Shouta Itoh, Tsuyoshi Hatamachi
Journal of Solar Energy Engineering, Transactions of the ASME 132 ( 4 ) 2010
Molten-Salt Tubular Absorber/Reformer "MoSTAR" Project: The Thermal Storage Media of Na2CO3-MgO Composite Materials Reviewed
Tatsuya Kodama, Nobuyuki Gokon, Shin-Ichi Inuta, Shingo Yamashita, Taebeom Seo
Journal of Solar Energy Engineering, Transactions of the ASME 131 ( 4 ) 0410131 - 0410138 2009.11
Double-walled reformer tubes using high-temperature thermal storage of molten-salt/MgO composite for solar cavity-type reformer Reviewed
Nobuyuki Gokon, Shin-ichi Inuta, Shingo Yamashita, Tsuyoshi Hatamachi, Tatsuya Kodama
International Journal of Hydrogen Energy 34 ( 17 ) 7143 - 7154 2009.9
Thermochemical two-step water splitting cycles by monoclinic ZrO2-supported NiFe2O4 and Fe3O4 powders and ceramic foam devices Reviewed
Nobuyuki Gokon, Hiroko Murayama, Ayumi Nagasaki, Tatsuya Kodama
SOLAR ENERGY 83 ( 4 ) 527 - 537 2009.4
New solar water-splitting reactor with ferrite particles in an internally circulating fluidized bed Reviewed
Nobuyuki Gokon, Shingo Takahashi, Hiroki Yamamoto, Tatsuya Kodama
Journal of Solar Energy Engineering, Transactions of the ASME 131 ( 1 ) 0110071 - 0110079 2009.2
Kinetics of CO2 reforming of methane by catalytically activated metallic foam absorber for solar receiver-reactors Reviewed
Nobuyuki Gokon, Yusuke Osawa, Daisuke Nakazawa, Tatsuya Kodama
International Journal of Hydrogen Energy 34 ( 4 ) 1787 - 1800 2009.2
Monoclinic zirconia-supported Fe3O4 for the two-step water-splitting thermochemical cycle at high thermal reduction temperatures of 1400-1600 degrees C Reviewed
Nobuyuki Gokon, Hiroko Murayama, Jun Umeda, Tsuyoshi Hatamachi, Tatsuya Kodama
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 34 ( 3 ) 1208 - 1217 2009.2
Molten-salt tubular absorber/reformer (MoSTAR) project: Metal-plate-bridged double tube reactor Reviewed
Tatsuya Kodama, Nobuyuki Gokon, Shin-Ichi Inuta, Shin-Go Yamashita, Tsuyoshi Hatamachi, Taebeom Seo
Proceedings of the ASME 3rd International Conference on Energy Sustainability 2009, ES2009 2 451 - 457 2009
REACTIVITY OF IRON-CONTAINING YSZ FOR A TWO-STEP THERMOCHEMICAL WATER SPLITTING USING THERMAL REDUCTION TEMPERATURES OF 1400-1500 degrees C Reviewed
Tatsuya Kodama, Eiji Hiraiwa, Nobuyuki Gokon
ES2008: PROCEEDINGS OF THE 2ND INTERNATIONAL CONFERENCE ON ENERGY SUSTAINABILITY, VOL 2 361 - 369 2009
Ferrite-loaded ceramic foam devices prepared by spin-coating method for a solar two-step thermochemical cycle Reviewed
Nobuyuki Gokon, Tatsuya Kodama, Ayumi Nagasaki, Ko-Ichi Sakai, Tsuyoshi Hatamachi
Proceedings of the ASME 3rd International Conference on Energy Sustainability 2009, ES2009 2 439 - 449 2009
Kinetics of CO2 reforming of methane by catalytically activated metallic foam absorber for solar receiver-reactors
Nobuyuki Gokon, Yusuke Osawa, Daisuke Nakazawa, Tsuyoshi Hatamachi, Tatsuya Kodama
2008 Proceedings of the 2nd International Conference on Energy Sustainability, ES 2008 2 371 - 383 2009
Thermochemical two-step water-splitting for hydrogen production using Fe-YSZ particles and a ceramic foam device Reviewed
Nobuyuki Gokon, Tomoki Hasegawa, Shingo Takahashi, Tatsuya Kodama
ENERGY 33 ( 9 ) 1407 - 1416 2008.9
Iron-containing yttria-stabilized zirconia system for two-step thermochemical water splitting Reviewed
Nobuyuki Gokon, Takayuki Mizuno, Yumiko Nakamuro, Tatsuya Kodama
Journal of Solar Energy Engineering, Transactions of the ASME 130 ( 1 ) 0110181 - 0110186 2008.2
Thermochemical two-step water splitting by ZrO2-supported NixFe3-xO4 for solar hydrogen production Reviewed
T. Kodama, N. Gokon, R. Yamamoto
SOLAR ENERGY 82 ( 1 ) 73 - 79 2008
Ken-ichi Shimizu, Rei Maruyama, Tsuyoshi Hatamachi, Tatsuya Kodama
The Journal of Physical Chemistry C 111 ( 17 ) 6440 - 6446 2007.4
Solar tubular reformer with molten-salt thermal storage - Design modification of the reactor tube and testing Reviewed
Tatsuya Kodama, Tsuyoshi Hatamachi, Daisuke Nakano, Youhei Igarashi, Nobuyuki Gokon
Proceedings of the ASME International Solar Energy Conference 197 - 204 2007
A two-step water splitting with ferrite particles and its new reactor concept using an internally circulating fludized-bed Reviewed
Nobuyuki Gokon, Takayuki Mizuno, Shingo Takahashi, Tatsuya Kodama
Proceedings of the ASME International Solar Energy Conference 205 - 214 2007
Reactive Fe-YSZ coated foam devices for solar two-step water splitting Reviewed
Tatsuya Kodama, Tomoki Hasegawa, Ayumi Nagasaki, Nobuyuki Gokon
PROCEEDINGS OF THE ENERGY SUSTAINABILITY CONFERENCE 2007 821 - 829 2007
Pillaring of high charge density synthetic micas (Na-4-mica and Na-3-mica) by intercalation of oxides nanoparticles Reviewed
Ken-ichi Shimizu, Yumiko Nakamuro, Ryoji Yamanaka, Tsuyoshi Hatamachi, Tatsuya Kodama
MICROPOROUS AND MESOPOROUS MATERIALS 95 ( 1-3 ) 135 - 140 2006.10
Double-walled reactor tube with molten salt thermal storage for solar tubular reformers Reviewed
T Hatamachi, T Kodama, Y Isobe, D Nakano, N Gokon
JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME 128 ( 2 ) 134 - 138 2006.5
KI Shimizu, S Itoh, T Hatamachi, Y Kitayama, T Kodama
JOURNAL OF MATERIALS CHEMISTRY 16 ( 8 ) 773 - 779 2006
Ru/Ni-Mg-O catalyzed SiC-foam absorber for solar reforming receiver-reactor Reviewed
Tatsuya Kodama, Takuya Moriyama, Takehiro Shimoyama, Nobuyuki Gokon
Solar Engineering 2005 697 - 705 2006
Double-walled reactor tube with molten salt thermal storage for solar tubular reformers Reviewed
T. Hatamachi, T. Kodama, Y. Isobe, D. Nakano, N. Goukon
Solar Engineering 2005 691 - 695 2006
Photocatalytic water splitting on Ni-intercalated Ruddlesden-Popper tantalate H2La2/3Ta2O7
K Shimizu, S Itoh, T Hatamachi, T Kodama, M Sato, K Toda
CHEMISTRY OF MATERIALS 17 ( 20 ) 5161 - 5166 2005.10
Acidic properties of sulfonic acid-functionalized FSM-16 mesoporous silica and its catalytic efficiency for acetalization of carbonyl compounds Reviewed
K Shimizu, E Hayashi, T Hatamachi, T Kodama, T Higuchi, A Satsuma, Y Kitayama
JOURNAL OF CATALYSIS 231 ( 1 ) 131 - 138 2005.4
Michael reaction of beta-ketoesters with vinyl ketones by iron(III)-exchanged fluorotetrasilicic mica: catalytic and spectroscopic studies
K Shimizu, M Miyagi, K Toshiki, T Hatamachi, T Kodama, Y Kitayama
JOURNAL OF CATALYSIS 229 ( 2 ) 470 - 479 2005.1
Degradation of hydrophobic organic pollutants by titania pillared fluorine mica as a substrate specific photocatalyst Reviewed
K Shimizu, H Murayama, A Nagai, A Shimada, T Hatamachi, T Kodama, Y Kitayama
APPLIED CATALYSIS B-ENVIRONMENTAL 55 ( 2 ) 141 - 148 2005.1
Structural investigations of functionalized mesoporous silica-supported palladium catalyst for Heck and Suzuki coupling reactions Reviewed
K Shimizu, S Koizumi, T Hatamachi, H Yoshida, S Komai, T Kodama, Y Kitayama
JOURNAL OF CATALYSIS 228 ( 1 ) 141 - 151 2004.11
Pd-sepiolite catalyst for Suzuki coupling reaction in water: Structural and catalytic investigations Reviewed
K Shimizu, R Maruyama, S Komai, T Kodama, Y Kitayama
JOURNAL OF CATALYSIS 227 ( 1 ) 202 - 209 2004.10
Selective photo-oxidation of benzene over transition metal-exchanged BEA zeolite Reviewed
K Shimizu, H Akahane, T Kodama, Y Kitayama
APPLIED CATALYSIS A-GENERAL 269 ( 1-2 ) 75 - 80 2004.8
Ultrafine na-4-mica: Uptake of alkali and alkaline earth metal cations by ion exchange
T Kodama, M Ueda, Y Nakamuro, K Shimizu, S Komarneni
LANGMUIR 20 ( 12 ) 4920 - 4925 2004.6
SO3H-functionalized silica for acetalization of carbonyl compounds with methanol and tetrahydropyranylation of alcohols
K Shimizu, E Hayashi, T Hatamachi, T Kodama, Y Kitayama
TETRAHEDRON LETTERS 45 ( 26 ) 5135 - 5138 2004.6
Solar methane reforming using a new type of catalytically-activated metallic foam absorber Reviewed
T Kodama, A Kiyama, T Moriyama, O Mizuno
JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME 126 ( 2 ) 808 - 811 2004.5
T Kodama, Y Isobe, Y Kondoh, S Yamaguchi, KI Shimizu
ENERGY 29 ( 5-6 ) 895 - 903 2004.4
Photocatalytic water splitting on hydrated layered perovskite tantalate A(2)SrTa(2)O(7)center dot nH(2)O ( A = H, K, and Rb) Reviewed
K Shimizu, Y Tsuji, T Hatamachi, K Toda, T Kodama, M Sato, Y Kitayama
PHYSICAL CHEMISTRY CHEMICAL PHYSICS 6 ( 5 ) 1064 - 1069 2004
Alkaline earth cation exchange with novel Na-3-mica: kinetics and thermodynamic selectivities
K Shimizu, K Hasegawa, Y Nakamuro, T Kodama, S Komarneni
JOURNAL OF MATERIALS CHEMISTRY 14 ( 6 ) 1031 - 1035 2004
Fe3+-exchanged fluorotetrasilicic mica as an active and reusable catalyst for Michael reaction
K Shimizu, M Miyagi, T Kan-no, T Kodama, Y Kitayama
TETRAHEDRON LETTERS 44 ( 40 ) 7421 - 7424 2003.9
Stepwise production of CO-rich syngas and hydrogen via methane reforming by a WO3-redox catalyst Reviewed
T. Kodama, T. Shimizu, T. Satoh, K.-I. Shimizu
Energy 28 ( 11 ) 1055 - 1068 2003.9
T. Kodama, A. Kiyama, T. Moriyama, T. Yokoyama, K-I. Shimizu, H. Andou, N. Satou
Energy & Fuels 17 ( 4 ) 914 - 921 2003.6
Catalytic direct 1,4-conjugate addition of aldehydes to vinylketones on N-methyl-3-Aminopropylated FSM-16
K Shimizu, H Suzuki, T Kodama, H Hagiwara, Y Kitayama
SCIENCE AND TECHNOLOGY IN CATALYSIS 2002 145 145 - 148 2003
Novel Na-3-mica: Alkaline earth cation exchange and immobilization
T Kodama, K Hasegawa, K Shimizu, S Komarneni
SEPARATION SCIENCE AND TECHNOLOGY 38 ( 3 ) 679 - 694 2003
Self-aldol condensation of unmodified aldehydes secondary-amine immobilised in FSM-16 catalysed by silica
K Shimizu, E Hayashi, T Inokuchi, T Kodama, H Hagiwara, Y Kitayama
TETRAHEDRON LETTERS 43 ( 50 ) 9073 - 9075 2002.12
T. Kodama, A. Kiyama, K.-I. Shimizu
Energy & Fuels 17 ( 1 ) 13 - 17 2002.10
Metal-oxide-catalyzed CO2 gasification of coal using a solar furnace simulator. (vol 14, pg 1323, 2000)
T Kodama, A Funatoh, T Shimizu, Y Kitayama
ENERGY & FUELS 16 ( 3 ) 802 - 802 2002.5
Kinetics of metal oxide-catalyzed CO2 gasification of coal in a fluidized-bed reactor for solar thermochemical process. (vol 15, pg 1200, 2001)
T Kodama, A Funatoh, K Shimizu, Y Kitayama
ENERGY & FUELS 16 ( 3 ) 802 - 802 2002.5
Stereoselective hydrogenation of linoleic acid over Ir/FSM-16 catalyst
Ken-ichi Shimizu, Toshiki Kan-no, Tsuyoshi Hatamachi, Shin-ichi Komai, Tatsuya Kodama, Yoshie Kitayama
Applied Catalysis A: General 228 ( 1-2 ) 75 - 82 2002
Synthesis of titania pillared mica in aqueous solution of acetic acid
T Kaneko, M Fujii, T Kodama, Y Kitayama
JOURNAL OF POROUS MATERIALS 8 ( 2 ) 99 - 109 2001.3
Thermochemical conversion of CH4 to C-2-hydrocarbons and H-2 over SnO2/Fe3O4/SiO2 in methane - Water co-feed system
T Shimizu, Y Kitayama, T Kodama
ENERGY & FUELS 15 ( 2 ) 463 - 469 2001.3
CO2 reforming of methane in a molten carbonate salt bath for use in solar thermochemical processes
T Kodama, T Koyanagi, T Shimizu, Y Kitayama
ENERGY & FUELS 15 ( 1 ) 60 - 65 2001.1
Thermochemical methane reforming using WO3 as an oxidant below 1173 K by a solar furnace simulator
T Shimizu, K Shimizu, Y Kitayama, T Kodama
SOLAR ENERGY 71 ( 5 ) 315 - 324 2001
Synthesis of Na-2-mica from metakaolin and its cation exchange properties
T Kodama, T Higuchi, T Shimizu, K Shimizu, S Komarneni, W Hoffbauer, H Schneider
JOURNAL OF MATERIALS CHEMISTRY 11 ( 8 ) 2072 - 2077 2001
Crystal-size control and characterization of Na-4-mica prepared from kaolinite
T Kodama, Y Harada, M Ueda, K Shimizu, K Shuto, S Komarneni, W Hoffbauer, H Schneider
JOURNAL OF MATERIALS CHEMISTRY 11 ( 4 ) 1222 - 1227 2001
Metal-oxide-catalyzed CO2 gasification of coal using a solar furnace
T Kodama, A Funatoh, T Shimizu, Y Kitayama
ENERGY & FUELS 14 ( 6 ) 1323 - 1330 2000.11
Thermochemical methane reforming using a reactive WO3/W redox system
T Kodama, H Ohtake, S Matsumoto, A Aoki, T Shimizu, Y Kitayama
ENERGY 25 ( 5 ) 411 - 425 2000.5
Thermochemical CO2 gasification of coal using a reactive coal-In2O3 system
T Kodama, A Aoki, H Ohtake, A Funatoh, T Shimizu, Y Kitayama
ENERGY & FUELS 14 ( 1 ) 202 - 211 2000.1
Simplified synthesis of Na-4-mica from kaolinite and its cation-exchange properties
T Kodama, S Komarneni
SEPARATION SCIENCE AND TECHNOLOGY 35 ( 8 ) 1133 - 1152 2000
Na-4-mica: simplified synthesis from kaolinite, characterization and Zn, Cd, Pb, Cu and Ba uptake kinetics
T Kodama, S Komarneni, W Hoffbauer, H Schneider
JOURNAL OF MATERIALS CHEMISTRY 10 ( 7 ) 1649 - 1653 2000
Cyclodehydration of diethylene glycol (DEG) catalyzed by clay mineral sepiolite
Y Kitayama, M Kamimura, K Wakui, M Kanamori, T Kodama, J Abe
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL 142 ( 2 ) 237 - 245 1999.6
A reactive redox system of metal oxide for a two-step thermochemical cycle for converting coal to upgraded chemical fuels of CO/H-2
T Kodama, T Shimizu, A Aoki, Y Kitayama
JOURNAL DE PHYSIQUE IV 9 ( P3 ) 343 - 348 1999.3
A two-step thermochemical conversion of CH4 to CO, H-2 and C-2-hydrocarbons below 1173 K
A Aoki, T Shimizu, Y Kitayama, T Kodama
JOURNAL DE PHYSIQUE IV 9 ( P3 ) 337 - 342 1999.3
Na-4-mica: Cd2+, Ni2+, Co2+, Mn2+ and Zn2+ ion exchange
Tatsuya Kodama, Sridhar Komarneni
Journal of Materials Chemistry 9 ( 2 ) 533 - 539 1999
Structure refinement of lithium ion conductors Li3Sc2(PO4)(3) and Li3-2x(Sc1-xMx)(2)(PO4)(3) (M = Ti, Zr) with x = 0.10 by neutron diffraction
T Suzuki, K Yoshida, K Uematsu, T Kodama, K Toda, ZG Ye, M Ohashi, M Sato
SOLID STATE IONICS 113 89 - 96 1998.12
Efficient thermochemical cycle for CO2 gasification of coal using a redox system of reactive iron-based oxide
T Kodama, A Aoki, T Shimizu, Y Kitayama, S Komarneni
ENERGY & FUELS 12 ( 4 ) 775 - 781 1998.7
Synthesis of Sn-incorporated folded sheets mesoporous materials (Sn-FSM-16)
Y Kitayama, H Asano, T Kodama, J Abe, Y Tsuchiya
JOURNAL OF POROUS MATERIALS 5 ( 2 ) 139 - 146 1998.5
Synthesis of titania pillared saponite in aqueous solution of acetic acid
Y Kitayama, T Kodama, M Abe, H Shimotsuma, Y Matsuda
JOURNAL OF POROUS MATERIALS 5 ( 2 ) 121 - 126 1998.5
Gas-liquid chromatographic analysis of geometrical and positional octadecenoic and octadecadienoic acid isomers produced by catalytic hydrogenation of linoleic acid on Ir/Al2O3
Y Kitayama, M Takahashi, H Sugiyama, T Kodama, M Okamura
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY 75 ( 1 ) 27 - 32 1998.1
Efficient thermochemical cycle for CO2 reduction with coal using a reactive redox system of ferrite
T Kodama, A Aoki, S Miura, Y Kitayama
ADVANCES IN CHEMICAL CONVERSIONS FOR MITIGATING CARBON DIOXIDE 114 383 - 386 1998
Efficient Two-Step Thermochemical Process Using Highly Reactive Metal Oxide for Conversion of High-Temperature Heat to Chemical Fuels
Recent Res. Devel. in Mat. Sci. 1 109 - 121 1998
Oxidative Coupling of Methane Using H<sub>2</sub>O as an Oxidant over Ferrite Catalysts
SHIMIZU T., KITAYAMA Y., KODAMA T.
J. Mag. Soc. Jpn 22 ( S1 ) 400 - 402 1998
New Ferrite Application for a Thermochemical CO<sub>2</sub> Reduction with Coal
MIURA S., AOKI A., KITAYAMA Y., KODAMA T.
J. Mag. Soc. Jpn 22 ( S1 ) 403 - 405 1998
New Synthesis Method of Ultrafine Ferrite by Reduction of Fe(III)-Tartrate Chelate Solution
KODAMA T., MIURA S., KITAYAMA Y., TAMAURA Y.
J. Mag. Soc. Jpn 22 ( S1 ) 440 - 442 1998
Stabilization of superionic conduction phase in Li3Sc2(PO4)(3) Reviewed
T Suzuki, K Yoshida, K Uematsu, T Kodama, K Toda, ZG Ye, M Sato
SOLID STATE IONICS 104 ( 1-2 ) 27 - 33 1997.12
Thermochemical conversion of coal and water to CO and H-2 by a two-step redox cycle of ferrite
T Kodama, S Miura, T Shimizu, Y Kitayama
ENERGY 22 ( 11 ) 1019 - 1027 1997.11
High-temperature conversion of CH4 to C-2-hydrocarbons and H-2 using a redox system of metal oxide
T Kodama, T Shimizu, A Aoki, Y Kitayama
ENERGY & FUELS 11 ( 6 ) 1257 - 1263 1997.11
Catalytic reduction of carbon dioxide on Ni-Cu alloys Reviewed
Y Kitayama, Y Watanabe, K Muramatsu, T Kodama
ENERGY 22 ( 2-3 ) 177 - 182 1997.2
Methanation of CO2 using ultrafine NixFe3-xO4
T Kodama, Y Kitayama, M Tsuji, Y Tamaura
ENERGY 22 ( 2-3 ) 183 - 187 1997.2
Preparation and CO2 methanation activity of an ultrafine Ni(II) ferrite catalyst
M Tsuji, T Kodama, T Yoshida, Y Kitayama, Y Tamaura
JOURNAL OF CATALYSIS 164 ( 2 ) 315 - 321 1996.12
Synthesis and characterization of ultrafine Mn(II)-bearing ferrite of type MnxFe3-xO4 by coprecipitation
T Kodama, M Ookubo, S Miura, Y Kitayama
MATERIALS RESEARCH BULLETIN 31 ( 12 ) 1501 - 1512 1996.12
Catalytic acceleration for CO2 decomposition into carbon by Rh, Pt or Ce impregnation onto Ni(II)-bearing ferrite
M Tsuji, T Yamamoto, Y Tamaura, T Kodama, Y Kitayama
APPLIED CATALYSIS A-GENERAL 142 ( 1 ) 31 - 45 1996.8
Preparation of large surface area nickel magnesium silicate and its catalytic activity for conversion of ethanol into buta-1,3-diene
Y Kitayama, M Satoh, T Kodama
CATALYSIS LETTERS 36 ( 1-2 ) 95 - 97 1996
T. Kodama, Y. Kitayama, M. Tsuji, Y. Tamaura
Journal of the Magnetics Society of Japan 20 ( 2 ) 305 - 308 1996
XRD AND MOSSBAUER STUDIES ON OXYGEN-DEFICIENT NI(II)-BEARING FERRITE WITH A HIGH REACTIVITY FOR CO2 DECOMPOSITION TO CARBON
T KODAMA, M TABATA, T SANO, M TSUJI, Y TAMAURA
JOURNAL OF SOLID STATE CHEMISTRY 120 ( 1 ) 64 - 69 1995.11
SYNTHESIS AND CHARACTERIZATION OF ULTRAFINE NICKEL(II)-BEARING FERRITES (NIXFE3-XO4,X=0.14-1.0)
T KODAMA, Y WADA, T YAMAMOTO, M TSUJI, Y TAMAURA
JOURNAL OF MATERIALS CHEMISTRY 5 ( 9 ) 1413 - 1418 1995.9
CO2 DECOMPOSITION TO CARBON BY ULTRAFINE NI(II)-BEARING FERRITE AT 300-DEGREES-C
T KODAMA, Y WADA, T YAMAMOTO, M TSUJI, Y TAMAURA
MATERIALS RESEARCH BULLETIN 30 ( 8 ) 1039 - 1048 1995.8
SYNTHESIS OF HYDROTALCITE WITH HIGH LAYER CHARGE FOR CO2 ADSORBENT
T YAMAMOTO, T KODAMA, N HASEGAWA, M TSUJI, Y TAMAURA
ENERGY CONVERSION AND MANAGEMENT 36 ( 6-9 ) 637 - 640 1995.6
REACTION CONDITION FOR THE SYNTHESIS OF ULTRAFINE PARTICLES OF THE HIGH-VACANCY-CONTENT ZN(II)-BEARING FERRITES FROM IRON(III) TARTRATE SOLUTION
T KODAMA, Y TAMAURA
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 78 ( 5 ) 1335 - 1342 1995.5
CO2 DECOMPOSITION TO CARBON WITH FERRITE-DERIVED METALLIC PHASE AT 300-DEGREES-C
T KODAMA, T SANO, T YOSHIDA, M TSUJI, Y TAMAURA
CARBON 33 ( 10 ) 1443 - 1447 1995
METHANATION OF CO2 ON H-2-REDUCED NI(II) OR CO(II)-BEARING FERRITES AT 200-DEGREES-C
M TSUJI, H KATO, T KODAMA, SG CHANG, N HESEGAWA, Y TAMAURA
JOURNAL OF MATERIALS SCIENCE 29 ( 23 ) 6227 - 6230 1994.12
DECOMPOSITION OF CO2 TO CARBON BY H-2-REDUCED NI(II)- AND CO(II)-BEARING FERRITES AT 300-DEGREES-C
T KODAMA, H KATO, SG CHANG, N HASEGAWA, M TSUJI, Y TAMAURA
JOURNAL OF MATERIALS RESEARCH 9 ( 2 ) 462 - 467 1994.2
CO2 DECOMPOSITION WITH MANGANO-WUSTITE
M TABATA, H KATO, T KODAMA, T YOSHIDA, M TSUJI, Y TAMAURA
JOURNAL OF MATERIALS SCIENCE 29 ( 4 ) 999 - 1003 1994.2
Decomposition of carbon dioxide to carbon by hydrogen-reduced Ni(II)-bearing ferrite
H. Kato, T. Kodama, M. Tsuji, Y. Tamaura, S. G. Chang
Journal of Materials Science 29 ( 21 ) 5689 - 5692 1994.1
METHANATION OF CO2 WITH H2-REDUCED MAGNETITE
T YOSHIDA, K NISHIZAWA, M TABATA, H ABE, T KODAMA, M TSUJI, Y TAMAURA
JOURNAL OF MATERIALS SCIENCE 28 ( 5 ) 1220 - 1226 1993.3
CO2 DECOMPOSITION WITH OXYGEN-DEFICIENT MN(II) FERRITE
M TABATA, Y NISHIDA, T KODAMA, K MIMORI, T YOSHIDA, Y TAMAURA
JOURNAL OF MATERIALS SCIENCE 28 ( 4 ) 971 - 974 1993.2
CARBON-DIOXIDE DECOMPOSITION INTO CARBON WITH THE RHODIUM-BEARING MAGNETITE ACTIVATED BY H-2-REDUCTION
K AKANUMA, K NISHIZAWA, T KODAMA, M TABATA, K MIMORI, T YOSHIDA, M TSUJI, Y TAMAURA
JOURNAL OF MATERIALS SCIENCE 28 ( 4 ) 860 - 864 1993.2
DECOMPOSITION OF CO2 AND CO INTO CARBON WITH ACTIVE WUSTITE PREPARED FROM ZN(II)-BEARING FERRITE
T KODAMA, M TABATA, K TOMINAGA, T YOSHIDA, Y TAMAURA
JOURNAL OF MATERIALS SCIENCE 28 ( 2 ) 547 - 552 1993.1
ADSORPTION OF CO2 ON OXYGEN-DEFICIENT MAGNETITE - ADSORPTION ENTHALPY AND ADSORPTION-ISOTHERM
K NISHIZAWA, T KODAMA, M TABATA, T YOSHIDA, M TSUJI, Y TAMAURA
JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS 88 ( 18 ) 2771 - 2773 1992.9
DECOMPOSITION OF CARBON-DIOXIDE TO CARBON WITH ACTIVE WUSTITE AT 300-DEGREES-C
T KODAMA, K TOMINAGA, M TABATA, T YOSHIDA, Y TAMAURA
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 75 ( 5 ) 1287 - 1289 1992.5
HIGH-VACANCY-CONTENT ZINC(II)-BEARING FERRITES FROM IRON(III) TARTRATE IN STRONGLY ALKALINE-SOLUTIONS
T KODAMA
JOURNAL OF MATERIALS CHEMISTRY 2 ( 5 ) 525 - 528 1992.5
High-vacancy-content ferrite with fine particles
T. Kodama, T. Itoh, M. Tabata, Y. Tamaura
Journal of Applied Physics 69 ( 8 ) 5915 - 5917 1991
The Formation of High-vacancy-content M(II)-bearing Ferrites (M=Ni and Cd) from the Strongly Alkaline Solutions of Fe(III)-tartrate, and Dextrose (Jointly Worked)
Ceramic Transactions 22 609 1991
Characterization of Zinc(II)-bearing Ferrites from the Strongly Alkaline Solutions of Fe(III)-tartrate, and Dextrose (Jointly Worked)
Ceramic Transactions 22 603 1991
HIGH-VACANCY-CONTENT MAGNETITES AND ZINC-BEARING FERRITES FROM IRON(III) TARTRATE IN STRONGLY ALKALINE-SOLUTION
Y TAMAURA, T KODAMA, T ITOH
JOURNAL OF THE AMERICAN CERAMIC SOCIETY 73 ( 8 ) 2539 - 2542 1990.8
Efficient thermochemical cycle for CO<sub>2</sub> reduciton with coal using a reactive redox system of ferrite
Studies in Suface Science and Catalysis 1998
42 ( 7 ) 12 - 19 2013.7
BEAゼオライト内に固定化したペルオキソ二核銅錯体によるベンゼンから二価フェノールへの選択光酸化反応
清水 研一, 丸山 怜, 赤羽 広也, 児玉 竜也, 北山 淑江
触媒 = Catalysts & Catalysis 47 ( 2 ) 75 - 77 2005.3
Cross-coupling reaction by FSM-16 immobilised Pd catalyst
SHIMIZU Ken-ichi, KOIZUMI Soichi, KODAMA Tatsuya, KITAYAMA Yoshie
46 ( 6 ) 533 - 535 2004.9
Flowability and reactivity of spherical Mn-doped ceria particles for a solar thermochemical two-step water splitting by a fluidized bed reactor
R. Kurosawa, T. Kodama, T. Kawamura, T. Nakano, S. Bellan
Grand Renewable Energy 2022 International Conference (GRE2022) 2022.12
各種セビオライト中の炭酸塩の除去および不純物イオンの置換サイト
粘土科学 2001.7
Substitution of Mg(II) in Sepiolite with Cu(II) in Aqueous Solution
KITAYAMA Yoshie, MURAOKA Masahiro, KODAMA Tatsuya, OMI Naohiro, OIZUMI Manabu
Nendo Kagaku 1996 The Clay Science Society of Japan
Reactive media and method of producing hydrogen
Tatsuya Kodama
Reactive media and method of producing hydrogen
Tatsuya Kodama
Method for producing hydrogen
Tatsuya Kodama, Nobuyuki Gokon
Method for producing hydrogen by means of thermochemical water-splitting, and device for producing hydrogen
Tatsuya Kodama, Nobuyuki Gokon
内循環流動層を用いた水熱分解装置及び水熱分解法
児玉竜也, 郷右近展之, 櫻井篤, 松原幸治
流動層を備えた太陽光集熱装置及びこれを用いた太陽光集熱方法
松原幸治, 櫻井篤, 児玉竜也, 郷右近展之
CONCENTRATED SOLAR HEAT RECEIVER, REACTOR, AND HEATER
Tatsuya Kodama, Koji Matsubara, Nobuyuki Gokon
内循環流動層を用いた石炭コークスのソーラーガス化装置およびガス化法
児玉竜也, 郷右近展之, 櫻井篤, 松原幸治
太陽光を利用した集熱蓄熱装置
児玉竜也, 郷右近展之, 松原幸治, 櫻井篤
Study on solar methane reforming and coal gasificatin to produce hydrogen
反応性セラミックによる集光熱/水素エネルギー転換に関する研究
新規膨潤性マイカのイオン交換に関する研究
集光太陽熱による天然ガス改質・石炭ガス化による水素製造に関する研究
Study on solar thermochemical water splitting cycle
Study on nevel inorganic ion exchangers
新潟日報文化賞 産業技術部門
2021.11 新潟日報社
11th SOLARIS Best Paper Award
2021.9 The Heat Transfer Society of Japan Hydrogen Production by Solar Fluidized Bed Reactor Using Ceria: Euler-Lagrange Modeling of Gas-solid Flow to Optimize the Internally Circulating Fludized Bed
Selvan Bellan, Tatsuya Kodama, Hyun-Seok Cho, Jin-Soo Kim
平成22年度日本エネルギー学会 進歩賞（学術部門）
2011.2 日本エネルギー学会 高温太陽集熱による水熱分解ソーラー水素製造技術の開発
The Solar Energy Division, Best Pater Award
2005.8 The American Society of Mechanical Engineers Ru/Ni-Mg-O Catalyzed SiC Foam Absorber for Solar Reforming Receiver-Reactor
財団 手島工業教育資金団工業技術研究賞
2002
第70春季年会講演奨励賞
1996
高エントロピー金属酸化物による太陽熱水分解水素製造サイクルの革新的展開
Grant number：24H00442
2024.4 - 2028.3
System name：科学研究費助成事業
Research category：基盤研究(A)
Awarding organization：日本学術振興会
児玉 竜也, Bellan Selvan, 石井 知彦, 長瀬 慶紀
Grant amount：\47710000 （ Direct Cost: \36700000 、 Indirect Cost：\11010000 ）
太陽集熱利用型CO2‐H2O共熱分解サイクルによる合成ガス製造
Grant number：20H00362
2020.4 - 2024.3
System name：科学研究費助成事業
Research category：基盤研究(A)
Awarding organization：日本学術振興会
児玉 竜也, Bellan Selvan, 長瀬 慶紀, 石井 知彦, 曹 賢石
Grant amount：\44850000 （ Direct Cost: \34500000 、 Indirect Cost：\10350000 ）
１．流動層反応器試験用に必要な量の高活性ドープセリアの微粒子をスプレードライ法で製造した。流動性に優れた真球状微粒子として製造することができた。反応性も共沈法で合成してきたドープセリアと同等であり、非ドープセリアと比較して3～4倍の活性が得られた。
２．並行して、さらなる高活性酸化還元金属酸化物の探索を行い、鉄系の高エントロピー酸化物において、ドープセリアよりも、さらに高活性の金属酸化物を見出した。
３．宮崎大学に設置している太陽集光システムで、集光エネルギー量の測定を行ったところ、地上反射鏡の経年劣化が原因と思われる太陽集光エネルギー量の著しい減少が観測された。これまでの流動層反応器の設計では太陽集光の照射しても反応温度にまで金属酸化物の温度をあげられないことが予想された。この状況に対応するためには、流動層型のみならず、移動層型反応器にも設計範囲を広げて、大型ソーラー反応器の設計を見直すことが必要となった。しがたって、ソーラー反応器数値解析モデル等により、流動層から移動層利用も含めた大型ソーラー反応器の再設計を行うこととした。
Development of thermochemical water-splitting hydrogen production reactor systems with a low temperature reactive ceramics to utilize concentrating solar thermal energy
Grant number：17H01376
2017.4 - 2020.3
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (A)
Awarding organization：Japan Society for the Promotion of Science
Kodama Tatsuya
Grant amount：\43680000 （ Direct Cost: \33600000 、 Indirect Cost：\10080000 ）
Solar thermochemical water splitting reactor systems by a metal oxide redox cycle, a fluidized bed reactor system for a large-scale (0.5-50MWth) application and a foam device reactor system for a small-scale (50kWth) application, are designed as the prototypes, via 3-100 kW reactors tests and the numerical simulation. These reactors are expected to utilize a high temperature concentrated solar thermal energy (1100-1500℃) to produce hydrogen. Novel spherical fine particles for the fluidized bed reactor and conical foam derives for the foam device reactor are successfully developed using the low temperature reactive ceramics of Mn-doped ceria, which have much greater reactivities than ones made with conventional or benchmark ceramic of undoped-ceria.
Development of water splitting device with thermal-photo-hybridized activity via solar demonstration
Grant number：16K14056
2016.4 - 2018.3
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Challenging Exploratory Research
Awarding organization：Japan Society for the Promotion of Science
Kodama Tatsuya, Kang Yong-Heack, Kim Jong-Kyu
Grant amount：\3770000 （ Direct Cost: \2900000 、 Indirect Cost：\870000 ）
This project aims at the development of water splitting device with a “thermal-photo-hybridized” activity via solar demonstration, in order to reduce the reaction temperature of solar two-step water splitting cycle with a redox metal oxide. It is well known that cerium oxide (ceria) has a high thermal activity as a working reactive ceramic (redox metal oxide) for solar “thermochemical” two-step water splitting cycle. In this project, iron oxide, which has “photochemical activity”, was doped into ceria, and then, small ceramic foams were coated with the iron-doped ceria powder. The prepared reactive foam devices were tested on activity for the two-step water splitting cycle under irradiation of artificial solar fluxes from a sun-simulator. Under the experiments, the new devices were found to split water at temperatures below 1300C while the conventional device without doping of iron-oxide needs temperatures above 1500C.
Development of solar concentrating thermochemical water splitting hydrogen production system via solar demonstration
Grant number：26249151
2014.4 - 2017.3
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (A)
Awarding organization：Japan Society for the Promotion of Science
Kodama Tatsuya, GOKON Nobuyuki, Cho Hyun Seok, Bellan Selvan, MATSUBA Tadashi, YOKOTA Masahisa, YOSHIDA Kazuo, Kang Yong-Heack, Hinkley Jeames
Grant amount：\40560000 （ Direct Cost: \31200000 、 Indirect Cost：\9360000 ）
In order to develop the prototype reactor system for water splitting to produce solar hydrogen by utilizing concentrated solar radiation in world sun-belt regions with abundant insolation, two types of the solar reactors (the conical foam device reactor type and the particle fluidized bed reactor type) for two-step thermochemical water splitting cycle using metal oxide redox pair (reactive ceramics) are developed. In this work, solar demonstrations of 30-40kWth scale reactors have proven that the two reactor concepts can split water to produce hydrogen utilizing concentrating solar thermal energy. For industrial application, the fluidized reactor system concept is suitable for MWth-scale solar hydrogen production plants since the hydrogen productivity per cycle is very high. On the other hand, the foam device reactor system concept is suitable for around 500kWth small hydrogen production systems.
Development of hot temperature fluidized bed solar receiver / thermal storage system for efficient solar power generation
Grant number：25289357
2013.4 - 2016.3
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B)
Awarding organization：Japan Society for the Promotion of Science
Matsubara Koji, NAGASE Yoshinori, Hiramoto Kazuhiko, Kodama Tatsuya, Sakurai Atsushi
Grant amount：\17420000 （ Direct Cost: \13400000 、 Indirect Cost：\4020000 ）
This study develops the fluidized bed solar receiver for efficient solar power generation. Since the solar receiver / reactor development project found that the cylindrical fluidized bed irradiated by concentrated light could increase the air and the particle temperature beyond 1000℃, this study deals development of numerical simulation methodology on fluidized bed and the experiment on irradiated fluidized bed with organized circulation, to propose new type of fluidized bed receiver. This new type fluidized bed receiver is based on the two-tower fluidized bed receiver which causes the organized circulation of particles by the aeration velocity difference between two towers. It was designed so that the particle can continuously enter and exit the receiver part. The experimental visualization revealed that the new fluidized bed can charge and discharge the particles continuously, to prove its applicability to the solar receiver / storage system.
Development of a solar gasification reactor of carbon resources by direct irradiation
Grant number：22560836
2010 - 2012
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (C)
Awarding organization：Japan Society for the Promotion of Science
HATAMACHI Tsuyoshi, KODAMA Tatsuya, KODAMA Tatsuya
Grant amount：\4420000 （ Direct Cost: \3400000 、 Indirect Cost：\1020000 ）
We aimed to validate the usefulness of solar gasification by beam-down solar concentrating system at Sun-belt using coal, biomass and so on. Stainless steel fluidized bed gasification reactors were made for direct lighting to reactant in lab scale. Coal coke and brown coal were tested as reactants by batch method using xenon arc lamp (radiant flux 3kW). As results, its were effective to increase reaction rate to reinforce insulation of reactor and to argument steam concentration in the case of steam gasification. It was effective to install a draft tube for the purpose of circulating reactant, too. Because it occurs to spread reaction zone. Besides, contrivance to increase fluidity of coke reflected that the light-to fuel energy conversion efficiency recorded up to 13%.
熱-光ハイブリット活性水分解デバイスの創製とそのソーラー試験
Grant number：22656215
2010 - 2011
System name：科学研究費助成事業
Research category：挑戦的萌芽研究
Awarding organization：日本学術振興会
児玉 竜也
Grant amount：\3560000 （ Direct Cost: \3200000 、 Indirect Cost：\360000 ）
本研究では,従来の高温太陽集熱をエネルギー源とする二段階水熱分解サイクルの反応媒体である水熱分解性セラミックの熱活性に,光半導体触媒の光活性を添加し,通常1000℃以上でしか作動しないサイクル反応を低温化することに挑戦する。すなわち熱-光ハイブリット活性型の反応性セラミックデバイスの創製に挑戦する。22年度は下記の研究成果が得られた。
研究代表者が開発したFe含有立方晶ジルコニアをゾルーゲル法で合成し,その際にセリウム等の光触媒金属酸化物を添加した反応性セラミック微粉体を合成した。この微粉体をスピンコート法でジルコニア,あるいはSiCのセラミッレ発泡体に担持し,反応デバイスの作製を行なった。この新規反応デバイスを3kW太陽炉シミュレータからの擬似太陽集光照射下で反応試験を行った。セリウムを添加しない反応デバイスと反応温度が低温化しているかを比較検討して結果,反応性セラミックの二段階反応の2つの反応,すなわち熱還元反応と水分解反応のうち,水分解反応について,従来の反応デバイスと比べて顕著な低温化が起こっていることが見出された。セリウムを添加しない場合は1100℃以上を必要としていたが,セリウムを添加すれば600～800℃でも十分に反応を行えることが見出された。後は,もう一つの反応の熱還元反応を低温化することができれば二段階反応全体を低温化することが出来る。これにはニッケル,コバルト酸化物等の添加が有効と考えられた。
反応性セラミックによる水熱分解ソーラー反応器の開発
Grant number：21360478
2009 - 2011
System name：科学研究費助成事業
Research category：基盤研究(B)
Awarding organization：日本学術振興会
児玉 竜也, 郷右近 展之
Grant amount：\19110000 （ Direct Cost: \14700000 、 Indirect Cost：\4410000 ）
本研究では,世界のサンベルト地域で得られる1000～1500℃の高温太陽集熱をエネルギー源として反応性セラミックによる二段階水熱分解サイクルによってソーラー水素の製造を行う2つの異なるコンセプトのソーラー反応器(発泡体デバイス型反応器および内循環流動層型反応器)のプロトタイプを3～5kWで作製し,これを太陽炉シミュレータあるいはパラボラディッシュ型太陽集光器(韓国インハ大学所有)を用いて性能評価することを目的とする。22年度は下記の研究成果が得られた。
1)発泡体デバイス型反応器については下記の成果が得られた。
発泡体デバイス反応器の2号器を作製し,新潟大の3kW太陽炉シミュレータによる擬似太陽集光による試験と,韓国インハ大学の5kWディッシュ型太陽集光器でのフィールド試験を並行して行った。反応体である発泡体でデバイスの反応性セラミック担持量等の合成条件を検討することにより,従来よりも発泡体デバイスの耐久性を向上させこの反応システムにおいて二段階水分解反応のサイクル化を行なうことが出来た。
2)内循環流動層型反応器については下記の成果が得られた。
内循環流動層反応器については,二段階サイクル反応を一段階プロセスとして実施できる従来にない画期的な反応器を考案している。,より安定に水素生成を行なうことを目的として反応器の設計改良を行い,これを新規に導入した5kW太陽炉シミュレータにより擬似太陽集光による性能試験を行った。同時に流動層に用いる反応性セラミック粒子の改良も行った結果,従来よりも一段階プロセスとして安定・定常的に水素生成を維持することに成功した。これに関しては国際特許出願を行なった。
低温水分解能を持つ熱-光ハイブリット活性セラミックデバイスの開発
Grant number：20656155
2008 - 2009
System name：科学研究費助成事業
Research category：挑戦的萌芽研究
Awarding organization：日本学術振興会
児玉 竜也, 郷右近 展之
Grant amount：\3600000 （ Direct Cost: \3600000 ）
本研究では,従来の高温太陽集熱をエネルギー源とする二段階水熱分解サイクルの反応媒体である水熱分解性セラミックの熱活性に,光半導体触媒の光活性を添加し,水熱分解サイクル反応を低温化することに挑戦した。初年度の研究により,研究代表者が見出した水熱分解性セラミックのFe_3O_4/ジルコニア担持体(Fe含有立方晶ジルコニア,あるいはFe_3O_4/単斜晶ジルコニア)にNiOをドープした水熱分解性セラミック粉体合成に成功し,さらにスピンコーティング法等の方法を応用して,この粉体を材料とした小型発泡体デバイスを作製することにも成功した。さらに,擬似太陽集光を直接デバイスに照射して2段階水分解反応を行う反応デバイスの活性試験を行い,NiOドーブによりデバイスの反応活性が向上することを確認した。今年度は下記の研究を実施する。今年度は下記の研究成果を得た。
1)作製の成功したFe-Ni含有立方晶ジルコニア発泡体デバイスについて,立方晶ジルコニアに対するNiOドープ量,またFeOドープを変化させ,反応デバイスの反応活性の向上を試みた。反応試験を太陽炉シミュレータで行い,FeO:NiO=2:1のドープ量が反応活性に対して最適なドープ量であることを見出した。
2)NiO同様に熱力学的見地,および光半導体活性の見地からCoOがFe_3O_4/ジルコニア担持体の反応活性を熱-光ハイブリット活性化によって高めると期待されるため,同様の手法でCoOをドープしたFe_3O_4/ジルコニア担持体粉体を合成し,その水熱分解活性を,赤外線イメージ炉を熱源として試験した。反応活性はほぼNiOドーブ型と同様の活性を得ることが出来た。
Developments of Reactive Water Splitting Ceramics and its Devices
Grant number：19360436
2007 - 2008
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B)
Awarding organization：Japan Society for the Promotion of Science
KODAMA Tatsuya, GOKON Nobuyuki
Grant amount：\20150000 （ Direct Cost: \15500000 、 Indirect Cost：\4650000 ）
熱-光ハイブリット活性セラミックによる低温水分解反応の開発
Grant number：18656274
2006 - 2007
System name：科学研究費助成事業
Research category：萌芽研究
Awarding organization：日本学術振興会
児玉 竜也, 清水 研一
Grant amount：\3500000 （ Direct Cost: \3500000 ）
本研究では,高温(1400℃)で進行する反応性セラミックによる2段階水熱分解サイクル反応を,半導体の光化学的効果を他金属ドープで反応性セラミックに添加するという手法で低温化する試みを行った。これを研究代表者が見出した水熱分解性セラミック「Fe^<2+>-Fe^<3+>含有型立方晶ジルコニア」で検討した。すなわち,反応性セラミックを反応デバイス化し,これに擬似太陽集光を直接照射して行う活性試験と,反応性セラミックの固体化学的・光触媒化学的な構造解析によるアプローチを併用して,低温水分解性セラミックの開発を行った。19年度は下記の研究成果を得た。
(1)1400℃における水素発生量増大化の検討:デバイスへの反応性セラミック担持量を増大することを目的に,スピンコート法へ担持法を変更した。担持プロセスを大幅に簡便化でき,鉄酸化物を約10wt%担持量するために数十回を要していた繰り返し担持を数回で到達できるようになり,担持量を増大させることが容易になった。1100-1400℃の水分解試験の結果,反応性セラミック粉末試料の熱活性のみの場合と比較して1.2倍に水分解活性が向上することが見出された。粉末試料の方が反応デバイスと比較して反応表面積が大きく,高活性が得られるはずであるが,逆の結果が得られたことは,期待通りに光触媒効果が関与して活性を向上させていることを示唆している。
(2)低温化の検討:担持量を増大させたデバイスでは水素発生量は増大したが,焼結が起きやすくなり反応温度は1200-1500℃とむしろ増大した。一方,鉄酸化物の粉末試料ではあるが,予めNiとMnをドープすると1400℃の反応活性が増大することが見出され,この手法で1400℃以下の反応活性も向上できると考えられる。
Development of conversion technology for concentrated solar thermal energy to solar hydrogen using continuous two step water splitting process
Grant number：17206100
2005 - 2006
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (A)
Awarding organization：Japan Society for the Promotion of Science
TAMAURA Yutaka, YOSHIZAWA Yoshio, KANEKO Hiroshi, HASEGAWA Noriko, KODAMA Tatsuya, NAKAJIMA Hiromitsu
Grant amount：\50700000 （ Direct Cost: \39000000 、 Indirect Cost：\11700000 ）
In the development on the rotary type solar reactor, the eight-step process of the 1^<st> model of the rotary type solar reactor (1kW), which had been fabricated previously on this project, has been improved to three-step process. The 2^<nd> model of the 10kW rotary type solar reactor was designed and fabricated (the specific ; diameter of the rotor= 50cm, To_2=1500℃, concentrated beam flux=2100kW/m^2, ωt=2.5 rpm. The performance test on the 2^<nd> model was carried out using the Ni-ferrite as reactive ceramics, and 80% recovery of the released O_2 and steam for H2 generation were obtained at To_2=1250℃. The H2 generation step was not achieved because of the limitation of the maximum temperature of To_2=125O℃. The simulator for solar concentration system was developed to estimate the practical flux magnitude in the Tokyo Tech Beam-down solar concentration system (TIT-BD system) at the focus point for using the rotary type solar reactor, and the CG software was developed to express the simulation result on TIT-BD system by CG. In the development on the heliostat, GPS system as a regulation system for tracking the sun was found to be superior to the three points recognition system. In the, development on the TIT-BD system, multi-ring central reflector system, cavity type molten salt receiver, and cross-beam heliostat field design were developed.
In the development of the reactive ceramics, the solid solution system between YSZ and the ferrites has been studied and was found to be used for the two-step water splitting process using rotary type solar reactor. In test of the O_2-releasing step of rotary type solar reactor, an intermediate stage of the reactive ceramics was discovered during a rapid temperature increase by the concentrated infra-red beam irradiation to the ceramics in the O_2-releasing step in the rotary type solar reactor.
Development of Reactive Ceramic Devices for High-Temperature Solar Thermo Water Splitting
Grant number：17360463
2005 - 2006
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B)
Awarding organization：Japan Society for the Promotion of Science
KODAMA Tatsuya, GOKON Nobuyuki, SHIMIZU Ken-ichi
Grant amount：\14500000 （ Direct Cost: \14500000 ）
In this research project, we have developed reactive ceramic devices to be used in solar thermochemical two-step water splitting cycle, for utilizing high-temperature solar heat in sun-belt regions. The main results are listed below :
1. Development of High Reactive Ceramic Powders
We investigated the other-metal doping effect on the ferrite supported on zirconia and found that Ni_<0.1>Fe_<2.0>O_4/ZrO_2 is the most reactive powder. On the other hand, we also found that, when yttrium-cubic-stabilized zircionia or YSZ is used as support instead of normal monoclinic zirconia, an iron-containing YSZ or Fe^<2+>-YSZ is formed by a high-temperature reaction between YSZ, and FeBBB_<3B>OB_<4B> supported on the YSZ at 1400℃ in an inert atmosphere, and that the FePPP^<2+P>-YSZ then reacts with steam and generate hydrogen at 1000-1100℃, to form FeP^<3+P>-YSZ that is re-activated by a thermal reduction in a separate step at temperatures above 1400℃ under an inert atmosphere.
2. Preparation and Reactivity Test of Reactive Devices
Zirconia foams coated with the Ni<1.0>Fe_<2.0>O4/ZrO_2or Fe_3O_4/YSZ particles were prepared as reactive devices and examined on reactivity for two-step water splitting cycle being performed alternately at temperatures between 1100 and 1400℃. Hydrogen successfully continued to be produced in the repeated 13-30 cycles, but foam device had cracks and broken after the repeated cycles. Ceramic foams with a higher thermal shock resistance, such as SiC foam, should be used as the matrix of the reactive devices.
3. Coating of SiC foam with Ziconia and Performance test for Thermal Resistance under Solar Irradiation
The SiC foam matrix was successfully coated with zirconia layers before FeBB_<3BB>OBB_<4BB> is applied on the matrix. On the other hand, the SiC foam matrix was examined on thermal resistance under solar irradiation using solar furnace and, as the results, we found that the SiC foam matrix has a good thermal resistance.
光-熱ハイブリット活性型水分解性セラミックの開発
Grant number：15656243
2003 - 2004
System name：科学研究費助成事業
Research category：萌芽研究
Awarding organization：日本学術振興会
児玉 竜也, 清水 研一
Grant amount：\3400000 （ Direct Cost: \3400000 ）
本研究は従来の反応性セラミックによる1500℃付近における2段階水分解熱化学サイクル,
M_xO_y=M_xO_<y-δ>+δ/2O_2 (高温酸素放出反応)
M_xO_<y-δ>+δH_2O=M_xO_y+δH_2 (低温水分解反応)
の反応系に、紫外-可視光応答性のある光半導体を導入して反応温度を低温化させる新しい「光-熱ハイブリット活性型反応性セラミック」を開発することを目的とする。本年度は下記の成果を得た。
1.反応試験用試料として反応性セラミックをディスク状のセラミック発泡体に担持した反応デバイスの作製を行った。光半導体で高温安定なSiCとZrO_2の発泡体を作製し、これにNiFe_2O_4/ZrO_2微粉体の反応性セラミックを担持した。石英窓付き反応器に設置し、模擬太陽集光を直接照射して1400℃に加熱し、光-熱ハイブリットによる活性化を試みた。この反応デバイスによる反応器は大型化も可能な設計であり、従来にない独特な方式と評価できる。
2.反応デバイスの構造変化を追跡し、ZrO_2発泡体のデバイスでは1400℃の活性化によりNiFe_2O_4を活性相のNi_<1/3>Fe_<2/3>Oへ還元できることを確認した。1000℃で水分解反応を行うと、水素を発生してNi_<1/3>Fe_<2/3>OがNiFe_2O_4へ再酸化され、サイクル反応が可能であることが見出された。
3.熱でのみ活性化を行った場合の反応効率を上回る結果は見られなかったが、これは、模擬太陽光照射下ではデバイスの温度分布が大きいため熱活性を十分に引き出せず、また光照射面積が十分でないことから光活性も十分に発現されてないことが要因と推察した。
4.今後は、本研究の成果を踏まえ、光照射が反応性セラミック粒子全体にいき渡る粉体流動層系で、光-熱ハイブリット活性化を検討することとし、試験用の石英窓を備えた流動層反応器を作製した。
Development Study on Solar Hydrogen Production with Concentrated-Solar-Beam Reactive Ceramics
Grant number：15206112
2003 - 2004
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (A)
Awarding organization：Japan Society for the Promotion of Science
TAMAURA Yutaka, SUEKANE Tetsuya, IHARA Manabu, KANEKO Hiroshi, HASEGAWA Noriko, KODAMA Tatsuya
Grant amount：\47060000 （ Direct Cost: \36200000 、 Indirect Cost：\10860000 ）
In the development of solar reactor for O2-releasing with Ni-ferrite (reactive ceramics), the two-step water splitting can be successfully proceeded repeatedly by temperature swing between 1473-1773K. For the Zn-ferrite system, a new solar reactor is designed based on the concept of recovering the powder mixture of ZnO+Fe3O4, and fabricated the practical testing instrument with a high temperature heat, for enhancing the reactivity of the Zn-ferrite system.
With this experiment, it was found that the solar reactor adopting the Zn-ferrite system can be developed for proceeding the O2-releasing process at the temperature around 1573K. Also, the cylindrical rotary reactor was newly designed and fabricated, with which the O2-releasing and H2-generation steps can be continuously repeated using infra red imaging furnace. It was confirmed that the cylindrical rotary reactor can work with a high efficiency for the two step water splitting process.
The optical system of the tower solar concentration plant was designed, and it was found that 3000 concentration can be obtained at the high solar angle, even though 2700 concentration is at least required, for the practical requirement of 2000 solar concentration.
When the endothermic reaction proceeds, 6.22mol/m2 of YSZ01NF is consumed for 2000kW/m2 of the beam flux, indicating that the thickness of the solid reaction bed is several cm for the dual type solar reactor (cylindrical rotary reactor). Thus, combining the newly developed reactive ceramics of YSZ01 NF and the dual type solar reactor, the solar hydrogen production can be realized by making the best use of a high solar beam flux through the solar/chemical energy conversion.
Development of catalytic devices for hydrogen production by concentrated middle/high-temperature solar heat
Grant number：15360509
2003 - 2004
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B)
Awarding organization：Japan Society for the Promotion of Science
KODAIRA Tatsuya, SHIMIZU Kenichi, ANDOU Hidemasa, SATOU Nobubhiro, MIZUNO Osamu
Grant amount：\12900000 （ Direct Cost: \12900000 ）
The purpose of the present research is to develop the highly-active catalytic devices for the following two solar thermochemical processes of converting concentrated middle/high-temperature solar heat to hydrogen in would "sun-belt" regions.
1.High-temperature (1000-1500℃) thermochemical two-step water splitting cycle by the reactive ceramics
M_xO_y=M_xO_<y-δ>+δ/2O_2
M_xO_<y-δ>+δH_2O=M_xO_y+δH_2
The highly reactive ceramics of the ZrO_2-supported ferrite in a fine powder form was improved on the reactivity. Then, we prepared the ceramic foam absorber/reactor device coated with the fine reactive ceramics.
(1)We previously showed that the Fe_3O_4/FeO phase transformation occurs on the "monoclinic" ZrO_2 support, associated with the redox reaction steps. In the present research, we examined the doping effect of other metal into ferrite, and found that the Ni-doping improved the reactivity : the chemical conversion of ferrite attained to about 70%.
(2)A new redox pair was found to serve as the working material on the "cubic" YSZ-supported ferrites : the FeO-ZrO_2 solid solution was formed, which decompose H_2O to in a separate step : the reproductively of the cycle was improved.
(3)The SiC or ZrO_2 foam matrix could be coated with fine ferrite/ZrO_2 to make the new absorber/reactor device.
2.Middle-temperature (500-1000℃) endothermic methane reforming
Our active metallic (Ni-Cr-Al) foam absorber, coated with Ru/Al_2O_3 catalyst, was examined to improve the activity on various preparation conditions : the optimal condition was determined. The absorber was scaled-up to a 14-cm diameter size and then tested in the solar furnace on the thermal properties. A more uniform temperature distribution was achieved on the irradiated metallic absorber, as opposed to the ceramic (alumina) absorber, below the flux distribution of the concentrated solar radiation due to the better thermal conductivity of the metallic foam. This would result in the increased overall reaction efficiency on the metallic foam absorber.
太陽熱/化学燃料転換のための低温作動型メタン改質触媒デバイスの開発
Grant number：13780404
2001 - 2002
System name：科学研究費助成事業
Research category：若手研究(B)
Awarding organization：日本学術振興会
児玉 竜也
Grant amount：\700000 （ Direct Cost: \700000 ）
吸熱反応であるメタンの二酸化炭素改質反応(CH_4+CO_2→2CO+2H_2)に集光太陽熱をプロセスヒートとして吸収させることで、製造燃料の持つエネルギーを原料メタンと比較して25%程度、太陽エネルギーによって増大させることが可能である。触媒を担持したセラミック発泡体プレート(触媒デバイス)に集光を直接照射し、これに反応ガスを流通して改質を行う大型のソーラー改質器が、欧米で既に開発されているが、この改質器を日本等の温帯地域で有効に利用するには、さらに高活性の触媒デバイスが必要である。本研究では、従来のセラミック発泡体に替えて、熱伝導効率の高い金属発泡体をデバイスに使用することが有効と考え、検討を行った。今年度は、昨年度に開発したRu/γ-Al_2O_3担持型Ni-Al-Cr合金発泡体(高温耐久性)の触媒デバイスについて合成条件を検討し、反応活性をさらに向上させることができた。今年度の研究成果の総括として、下記の2点が見出された。
1)本研究のRu/γ-Al_2O_3担持金属発泡体は、太陽集光のエネルギー密度が低い場合に従来のRu/γ-Al_2O_3担持セラミック発泡体を超える反応効率を実現する。集光のエネルギー密度が200kW/m^2程度のとき、従来の触媒デバイスではエネルギー転換率が高々45%程度であるのに対し、本研究の金属発泡体触媒デバイスでは70%を超えるエネルギー転換率を達成することができた。コスト的にも高価なRhに替えて、より安価なRuを使用できるので触媒デバイスのコストダウンができる。
2)本研究の金属発泡体触媒デバイスは、集光のエネルギー密度が高い場合においても、そのエネルギー分布が不均一なときに、従来のセラミック発泡体よりも高い反応効率を実現する。
これらの特性は金属発泡体の良熱伝性によるものと考えられる。200kW/m^2の集光エネルギー密度は、日本等の温帯地域で1000倍程度の集光で容易に達成できる。実用化のためには、今後、本反応デバイスの大型化による反応試験が必要である。
Study on Solar Hydrogen Production using Concentrated-Solar-Heat Reactive Ceramics
Grant number：12308022
2000 - 2001
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (A)
Awarding organization：Japan Society for the Promotion of Science
TAMAURA Yutaka, TSUJI Masamichi, KANEKO Hiroshi, KODAMA Tatsuya
Grant amount：\40800000 （ Direct Cost: \37800000 、 Indirect Cost：\3000000 ）
1)A laboratory-scale solar reactor which could be practically applicable for industrial technology was fabricated and its performance for solar hydrogen production by two-step water splitting using the two-solid-phase ceramics with the Zn/ferrite system was evaluated. The two-step water splitting consists of 1) the O_2-releasing step of ZnFe_2O_4=Zn+2/3Fe_3O_4+2/3O_2 and 2) the H_2 production step of Zn+2/3Fe_3O_4+4/3H_2O=ZnFe_2O_4+4/3H_2. The temperature for the O_2-releasing step is around 1500℃, which is lower by about 200-300℃ than for the Zn/ZnO system.
2)Based on the Zn/ferrite system, we have found out more feasible two-solid-phase ceramics with ZnO/Mn-ferrite system, which can be operated at temperatures around 1000℃ for the 0_2-releasing step. This temperature (1000℃) is the lowest for the 0_2-releasing step of the two-step water splitting using metal oxides. The solar reactor for this ZnO/Mn-ferrite system was designed to be operated by repetition of the two-steps for solar hydrogen production using the phase transition between mono phase and two phases. The paper on the experimental results concerning the ZnO/Mn-ferrite system was presented at the International Solar Energy Congress, which was held at Adelaide (Australia) in Nov.2001. At this congress, we had a meeting to discuss on the solar reactor with the international collaboration members of this study at the Australia University.
3)The beam-down solar concentrating system, which had been fabricated at TIT (Tokyo Institute of Technology) in laboratory scale, was modified to improve the concentrating performance by expanding reflection mirror area by two-times, and the relationship between the focus image distribution and concentrating system was examined. To develop an original technology belonging to Japan for heliostat, the heliostat which had been made to be used for the beam-down solar concentrating system was redesigned, and the improvement points were extracted. With those improved beam-down solar concentrating system, ZnO/Mn-ferrite system was examined for the solar/chemical energy conversion efficiency.
Synthesis of Titania Pillared Clays in An Aqueous Solution of Organic Acid and Its Application for Functional Material
Grant number：11555235
1999 - 2001
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B)
Awarding organization：Japan Society for the Promotion of Science
KITAYAMA Yoshie, KIJIMA Hiroyuki, MATSUDA Yasuhiro, KODAMA Yatsuya
Grant amount：\10400000 （ Direct Cost: \10400000 ）
From the environmental point of view, the soft synthetic methods of TiO_2-pillared and ZrO_2-pillared clays, such as montmorillonite, saponite and mica, have been studied in a dilute aqueous solution of acetic acid, since TiO_2-pillared clays have been usually prepared in HCl solution which brings environmental hazards due to its high reactivity and stimulus. Utilizations of the synthesized TiO_2-pillared clays were investigated.
(1) We found that TiO_2-pillared mica showed extremely high activity for the complete photodecomposition of organochlorine pesticides, especially for a photodecomposition of y-hexaxhrolo-cyclohexane that could not be decomposed by TiO_2 photocatalyst alone. The high activity of TiO_2-pillared mica is attributed to its affinity for y-hexaxhrolo-cyclohexane.
(2) Characteristic photocatalytic properties of TiO_2-pillared clays were observed in oxidation of benzene and decomposition of carboxylic acids.
In oxidation of benzene, catechol was produced predominantly by using TiO_2 alone. On the other hand, by using TiO_2-pillared mica and TiO_2-pillared saponite catalysts, maleic acid was successively produced via phenol and catechol formation. TiO_2-pillared montmorillonite showed different catalytic activity. Resosinol and phenol were predominantly produced. These results indicate that the reaction path of benzene photo-oxidation may be attributed tfc property of the clay itself pillaring with TiO_2.
In photocatalytic decomposition of organic acids, dependency of molecular size of organic acid on the catalytic activity of TiO_2-pillared clays was investigated. The photocatalytic activity of TiO_2-pillared clays decreased with an increase of the molecular size of the carboxylic acid. Since the photocatalytic activity of TiO_2-pillared saponite shows the lowest activity for the decomposition of carboxylic acids, TiO_2-pillared saponite can be possible to use as an effective UV protector of cosmetics.
太陽熱/化学エネルギー低温転換を目指した太陽光石炭ガス化触媒の開発
Grant number：11780365
1999 - 2000
System name：科学研究費助成事業
Research category：奨励研究(A)
Awarding organization：日本学術振興会
児玉 竜也
Grant amount：\2100000 （ Direct Cost: \2100000 ）
本研究は、集光太陽熱を化学エネルギー(化学燃料:CO及びH_2)へ高効率で転換する、二酸化炭素による石炭のソーラーガス化システムを構築することを目的として、太陽光石炭ガス化反応に高活性を示す触媒の開発を行うものである。触媒には、石炭灰からの分離回収が可能であることが必要であり、その分離回収プロセスも検討する。
1 本研究では、ZnO、In_2O_3触媒を高温(1000-1300℃)でZn(g),In_2O(g)として石炭灰から気化分離し、直ちに酸化することでZnO、In_2O_3として回収、再利用するプロセスを提案している。小型の反応器を使って、石炭の固定相ガス化の後、ZnO、In_2O_3触媒の高温分離を1150℃においてメタン-CO_2混合ガス気流中で試験した。95〜98%のZn、Inが石炭灰から気化分離された。反応器出口に設置した冷却トラップには、それぞれZnO,In_2O_3粒子が析出し、Zn(g),In_2O(g)を通して触媒が高効率で分離できることが見出された。
2 鉄酸化物触媒(Fe_2O_3あるいはFe_3O_4)は安価で環境に無害であり、ガス化後の鉄を含んだ石炭灰は、製鉄プラントの高炉に導入して容易に鉄を製鉄として回収できる。そこで赤外線照射小型流動層ガス化装置により触媒活性を試験した。その結果、含有率10wt%、800-900℃でガス化速度を1.5〜2倍に向上させる活性のあることが見出された。
3 小型の石炭流動層反応器を使って3KWキセノンランプ模擬太陽光の直接照射により、ZnO、In_2O_3、Fe_3O_4触媒の石炭ガス化活性を試験した。照射光エネルギー密度は最大で480kWm^<-2>までしか上げることができなかったが、太陽光/化学エネルギー転換率がIn_2O_3触媒(8wt%)により3倍(6%)に向上できることが見出された。
Studies on the Thermochemical Cycle for Heat/Chemical Energy Conversion by a hybrid use of Natural Gas/Unutilized Heat
Grant number：10558072
1998 - 2000
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B).
Awarding organization：Japan Society for the Promotion of Science
KODAMA Tatsuya, FUJII Yoshio, KITAYAMA Yoshie
Grant amount：\6800000 （ Direct Cost: \6800000 ）
Thermochemical redox Cycles for converting methane to calorie-upgraded chemical fuels of H_2, CO and C_2-hydrocarbon were investigated for the purpose of efficiently converting unutilized heat, such as concentrated solar heat, to chemical fuels below 1273 K.The following thermochemical cycles using a metal-oxide redox system were examined.
1. Methane reforming/Water Decomposition Cycle
CH_4+M_xO_y→M_xO_<y-m-n-1>+(1-n)CO+nCO_2+(2-m)H_2+mH_2O
M_xO_<y-m-n-1>+(m+n+1)H_2O→M_xO_y+(m+n+1)H_2
The reactive working materials of WO_3/ZrO_2 and Ni_<0.39>Fe_<2.61>O_4/ZrO_2 were prepared for this redox cycle. Especially, the cycle using Ni_<0.39>Fe_<2.61>O_4/ZrO_2 could be repeated below 1173K, yielding 40-60% methane conversion. The syngas produced in the first reaction step has a H_2/CO molar ratio of about two, which is suitable for methanol production. Also almost pure hydrogen was obtained in a separate second step.
2. Methane Coupling/Water Decomposition Cycle
2CH_4+M_xO_y→M_xO_<y-2>+C_2H_4+2H_2O
M_xO_<y-2>+2H_2O→M_xO_y+2H_2
The reactive working material of SnO_2/Fe_3O_4/SiO_2 was prepared for this cycle. methane was also highly selectively converted to C_2-hydrocargon and H_2 by a single-step reaction mode of co-feeding methane and steam over SnO_2/Fe_3O_4/SiO_2 at 1173K.In comparison with earlier studies on methane coupling using steam as an oxidant, our experimental data gave the higher C_2-formation rate with a high C_2-selectivity.
Synthesis of Titania Pillared Clays and Its Application for Photocatalyst
Grant number：10650821
1998 - 2000
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (C)
Awarding organization：Japan Society for the Promotion of Science
KITAYAMA Yoshie, KODAMA Tatsuya
Grant amount：\2900000 （ Direct Cost: \2900000 ）
The preparation of TiO_2-pillared clays was carried out in an dilute acetic acid solution to prevent the pollution of the environment and the decomposition of the clay itself. The titanium organic complex was formed by the reaction between titanium tetra-isopropoxide and acetic acid. The intercalation of titanium organic complex into the interlayer of clays was carried out in an aqueous solution of acetic acid. TiO_2-pillared clays, such as aconite, mica and montmorillonite, were prepared by the calcinations of the titanium organic complex intercalated into the interlayer of clays. Characterizations of the products were carried out by measurements of XRD, XPS, surface area, pore size distribution. The TiO_2-pillared clays obtained in this study showed high surface areas and homogeneous pore size distributions. ZrO_2-pillared clays and Ti_xZr_<1-x>O_2 could be obtaind by the same preparation method as TiO_2-pillared clays
Photocatalytic activity of the TiO_2-pillared clays were studied for the oxidation of benzene which was suspended in water. Catechol was produced predominantly in the photocatalytic oxidation of benzene by using TiO_2 alone. On TiO_2-pillared mica, after phenol and catechol were produced in the initial stage of the reaction, mareic acid was formed predominantly with an increase of reaction time. On TiO_2-pillared aconite, phenol and hydroquinon were produced, then mareic acid increased with an increase of reaction time. TiO_2-pillared montmorillonite showed different catalytic activity. Resosinol and phenol were predominantly. These results indicate that the reaction path of benzene photoxidation may be attributed to property of the clay itself pillaring with TiO_2.
熱/化学エネルギー低温転換を目指した石炭利用型水分解熱化学サイクルの開発
Grant number：09780455
1997 - 1998
System name：科学研究費助成事業
Research category：奨励研究(A)
Awarding organization：日本学術振興会
児玉 竜也
Grant amount：\2000000 （ Direct Cost: \2000000 ）
本研究は、外熱式石炭ガス化反応による集光太陽熱/化学エネルギー転換を行うことを目的として、反応性セラミックを媒体とした以下の2段階熱化学サイクルを検討するものである。
CH_n(coal)+metal oxide→CO+n/2H_2+metal (1段目)
metal+H_2O or CO_2→H_2 or CO+metal oxide (2段目)
上式にあるように2段目の反応では水蒸気の他、二酸化炭素を反応させて一酸化炭素を得ることも可能である。この場合、全反応は石炭のCO_2ガス化反応[CH_n+CO_2→2CO+n/2H_2]となり、水蒸気の場合と同様、太陽熱/化学エネルギー転換ができる。本年度はこちらのサイクルも検討課題に加えた。反応試験は固定床方式、900℃以下で行った。反応性セラミックとして鉄酸化物(フェライト)系を検討した結果、In-フェライトが最も活性が高く、触媒を用いない場合の約3倍の速度で石炭の水蒸気あるいはCO_2ガス化が行えることが見出された。石炭灰からのフェライトの分離回収は磁気分離が考えられる。しかし、磁気分離速度を考慮すると、このプロセスが律速となり全体的な石炭ガス化効率を低下させると予想される。そこで、セラミックを高温(1000℃程度)で気化し、石炭灰から分離回収するプロセスを考案した。既にフェライト系以外ではIn_2O_3がIn-フェライトと同等の高活性を有することを見出しているが、これを分離回収時に高温・還元雰囲気でIn_2O(g)とすれば高速で反応性セラミックを石炭灰から回収できる可能性がある。反応後の石炭灰+In_2O_3を1000℃でCH_4/CO_2(P_<CH4>=50%)混合ガスで処理した結果、石炭灰から82%のInを気化して分離することができた。今後はさらなる回収効率の向上、流動床方式による反応試験、反応システムと分離回収システムの結合を検討していく必要がある。
無機層状化合物のイオン交換
1997
Grant type：Competitive
Study on solar thermochemical water splitting cycle for H<sub>2</sub> production
1997
Grant type：Competitive
Study on solar thermochemical, natural-gas reforming and coal gasification to produce hydrogen
1997
Grant type：Competitive
Ion Exchange by novel inorganic materials
1997
Grant type：Competitive
水分解熱化学サイクルの研究
1997
Grant type：Competitive
太陽熱による天然ガス改質・石炭ガス化水素製造システムの研究
1997
Grant type：Competitive
Synthesis of Iithium ion conductors with an average structure
Grant number：08455405
1996 - 1997
System name：Grants-in-Aid for Scientific Research
Research category：Grant-in-Aid for Scientific Research (B)
Awarding organization：Japan Society for the Promotion of Science
SATO Mineo, KODAMA Tatsuya
Grant amount：\500000 （ Direct Cost: \500000 ）
The present study has been aimed to obtain fundamental aspects on the design for a room temperature superionic conducting material, Li_3M_2 (PO_4)_3 (M=Sc and In), which has a so called average structure at a high temperature. In order to obtain the superionic conducting phase Li_3M_2 (PO_4)_3 (M=Sc and In), several kinds of aliovalent ions such as Mg^<2+>, Ti^<4+>, Zr^<4+>, Sn^<4+>, Hf^<4+>, Nb^<5+>, and Ta^<5+> were substituted for the M site. The differential thermal analysis indicated that no phase transition existed in the divalent ion substituted samples with the substituted ratio over 5 mol%, the tetravalent ion substituted samples with the ratio over 5 mol%, and the pentavalent ion substituted samples with the ratio over 2.5 mol%. The highest ionic conducting materials, which were found in the Ti-and Zr-substituted samples, has a quite higher room temperature conductivity by three orders of magnitude than that of the unsubstituted samples. The neutron diffraction measurements confirmed the stabilization of the high temperature phase at room temperature in the substituted samples, and also confirmed a disorder of Li ion distribution among three kinds of available sites, giving a driving factor to the stabilization of the high temperature phase. The substituted materials could be a promising material for the solid electrolyte in a solid state lithium battery or a chemical sensor.
We also investigated the stabilization of the high temperature phase of Li_3V_2 (PO_4)_3, which has the same structure as that of Li_3M_2 (PO_4)_3. The stabilization of the high temperature phase was also observed in this compound by substituting 10 mol% of Zr for M sites. The charge-discharge capacity of an electrochemical lithium cell where this material was used as a cathode material was found to be improved by 20%.
反応性セラミック利用型水素製造熱化学サイクルを目指した新材料フェライトの開発
Grant number：08780470
1996
System name：科学研究費助成事業
Research category：奨励研究(A)
Awarding organization：日本学術振興会
児玉 竜也
Grant amount：\1100000 （ Direct Cost: \1100000 ）
1200℃以下で下記の水分解熱化学サイクルを構築することを目的として、反応媒体となる反応性セラミック新材料の開発を、複合鉄酸化物(フェライト)のredox系で検討した。
MFe_2O_4→MFe_2O_<4-x>+x/2O_2(酸素放出反応)
MFe_2O_<4-x>+xH_2O→xH_2+MFe_2O_4(水分解反応)
Zn(III)-、Mn(II)-フェライトに加え、マグネタイト(Fe_3O_4)、Ni(II)-、Mg(II)-、Co(II)-、In(II)-フェライトの反応性を調べた。比表面積を大きくし、反応を有利にするために粒径20-50nmの超微粒子を合成し、赤外線イメージ炉で作製した太陽炉モデルの反応炉で実験を行った。酸素放出反応に対する反応性を700℃の低温で速度論的に解析するため、炭素(活性炭)を還元剤として加えた。その結果、M=Zn<Mn<Fe<Co<Mg<In<Niの順で格子酸素の放出速度が増大することがわかった。さらにMg(II)以下のフェライトでは準安定ウスタイトで還元が止まるに対し、In(III)、Ni(II)ではα-Fe+In、Ni-Fe合金の金属相まで還元が進行することが見出された。Ni(II)-フェライトについてはNiとの合金化で金属鉄の生成自由エネルギーが低下することが原因と考えられるが、金属Inが独自に形成されるIn(III)-フェライトでは、Fe(II)への電子の授与にInが触媒的に関与するという興味深い還元機構が推察される。これら金属相は500℃で水蒸気を分解して水素を生成し、ほぼ完全にフェライト相に再酸化されることが確認された。次に、In(III)-、Ni(II)-フェライトで活性炭を用いず900℃以下においてN_2気流中での酸素放出反応を試みた結果、金属相の生成はほとんど起らなかった。これらフェライトにさらに改良を加える必要があるが、本研究で見出されたNi(II)-フェライトの低温のおけるNi-Fe合金への転移を、さらにInの触媒効果を利用し低温化することが期待でき、現在、Ni(II)-In(III)-フェライトによって検討中である。
物理化学I
エネルギー関連国際学会コミュニケーション法
ソーラー水素エネルギー概論
統合化学入門
エネルギー化学特論
素材平衡化学
技術文献リサーチA
技術文献リサーチC
技術文献リサーチB
水素エネルギー製造・輸送論
集光・集熱技術論
技術文献リサーチD
物理化学実験(工)
工学リテラシー入門(化学材料分野)
物理化学IV
材料生産システム博士セミナーⅡ
材料生産システム博士特定研究Ⅲ
材料生産システム博士セミナーⅢ
材料生産システム博士特定研究Ⅱ
ソーラー水素エネルギー国際会議コミュニケーション
中間発表
素材生産科学コース演習
材料生産システム博士特定研究Ⅰ
材料生産システム博士セミナーⅠ
外国語論文解説・討論Ⅰ
水素エネルギーシステムデザイン演習・実習Ⅰ
素材生産科学文献詳読Ⅱ
材料生産システム特定研究Ⅰ
素材生産科学特別演習
素材生産科学セミナーⅠ
材料生産システム特定研究Ⅱ
研究発表演習・発表
素材生産科学セミナーⅡ
素材生産科学文献詳読Ⅰ
リサーチキャンプ
統合化学入門
自然科学総論Ⅱ
卒業研修
工学リテラシー入門(化学システム工学科)
化学技術英語
物理化学III
化学システム工学入門
卒業研究
最先端技術を支える化学 I
エネルギー化学特論
素材平衡化学
論文輪講I
物理化学実験
論文輪講II
物理化学II
卒業基礎研究
応用化学演習III
応用化学実習
化学熱力学
