ᚑくᄢቇℂᎿቇ⎇ⓥႎ๔
J. Fac. Sci. Tech., Seikei Univ.
Vol.45 No.2 (2008) pp.27-31㧔ᣂછ⠪⺰ᢥ㧕ࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ࠍᜂ૕ߣߒߚ 0K ⸅ᇦࠍ↪޿ߚࡔ࠲ࡦ᳓⫳᳇ᡷ⾰෻ᔕߦࠃࠆ᳓⚛⵾ㅧᶆፒ ᶈᐔ Hydrogen Production by steam reforming of methane over Ni catalysts supportedon perovskite-type oxides
Kohei URASAKI*1ABSTRACT 㧦 Steam reforming of methane over nickel catalysts supported on a variety ofperovskite-type oxides, including LaAlO3, SrTiO3, BaTiO3, LaFeO3 and La0.4Ba0.6Fe0.2Co0.8O3-δ
were performed at 1073 K and 0.1 MPa. Ni/LaAlO3 and Ni/SrTiO3 showed high catalytic activities.
Temperature-programmed reduction measurements confirmed that the lattice oxygen in perovskites
was released by the reduction with hydrogen and partially recovered by steam during the steam
reforming reaction. It was found that all of recovered lattice oxygen could oxidize methane to give
carbon monoxide and carbon dioxide. We consider that the lattice oxygen participates in theoxidation of CHx fragments adsorbed on metallic Ni, leading to the suppression of the formation of
inactive carbonaceous species which cause catalyst deactivation.
Keywords㧦Steam reforming, Catalyst, Nickel, Perovskite, Hydrogen(Received September 25, 2008) ߘߩ৻ᣇߢㄭᐕ㐿⊒߇ㅴ߼ࠄࠇߡ޿ࠆ㧘࿕૕㜞ಽሶᒻ㧝㧚ߪߓ߼ߦΆᢱ㔚ᳰ↪᳓⚛⵾ㅧࡊࡠ࠮ࠬߦ὇ൻ᳓⚛ߩ᳓⫳᳇ᡷ⾰෻ ᳓⚛ߪ㧘ࠕࡦࡕ࠾ࠕ⵾ㅧࡊࡠ࠮ࠬ߿⍹ᴤ♖⵾ࡊࡠ࠮ࠬᔕࠍ↪޿ࠆ႐ว㧘ⵝ⟎ߩዊဳൻ߇᳞߼ࠄࠇࠆߎߣ߿㧘Ꮏࠍᆎ߼㧘ᄙߊߩ↥ᬺߦ߅޿ߡ㊀ⷐߥ‛⾰ߢ޽ࠅ㧘Ꮏᬺ⊛ᬺࡊࡠ࠮ࠬߢߪ᳞߼ࠄࠇߥ޿㧘㗫❥ߥ⿠േ஗ᱛࠍ઻߁㐳ߦߪ㧘ᄤὼࠟࠬ㧘LPG㧘࠽ࡈࠨ╬ߩ὇ൻ᳓⚛ߥߤࠍේᢱ޿ㆇォᤨ㑆߇᳞߼ࠄࠇ㧘ߘߩ⚿ᨐߣߒߡᓥ᧪ߩᎿᬺ⸅ᇦߣߒ㧘એਅߢ⴫ߐࠇࠆ᳓⫳᳇ᡷ⾰෻ᔕߦࠃࠅ⵾ㅧߐࠇࠆ‫ޕ‬એ਄ߦ㜞޿ᵴᕈ㧘⠴὇⚛ᨆ಴቟ቯᕈࠍ᦭ߔࠆ⸅ᇦ߇ᣂߚ

CH4 + H2O Ϻ CO + H2O∆H0298 K = 206 kJ mol-1ߦᔅⷐߣߥࠅ㧘ㄭᐕ⋓ࠎߦᣂⷙ᳓⫳᳇ᡷ⾰෻ᔕ↪⸅ᇦߩCnHm + nH2O ϺnCO + (m/2 + n)H2㐿⊒߇ߥߐࠇߡ޿ࠆ‫ޕ‬ᄢ߈ߥๆᾲ෻ᔕߢ޽ࠆߚ߼㧘1073 K ⒟ᐲߩ㕖Ᏹߦ㜞޿ ߎߩࠃ߁ߥ⁁ᴫߩਅ㧘⪺⠪ࠄߪㄭᐕ㧘㜞ᵴᕈ߆ߟ὇⚛
ᨆ಴ࠍᛥ೙ߒ㜞޿቟ቯᕈࠍ߽ߟ Ni ⸅ᇦߩ㐿⊒ࠍ⋡ᜰߒ㧘෻ᔕ᷷ᐲ߇ᔅⷐߢ޽ࠅ㧘Ꮏᬺ⊛ߦߪ㧘⠴ᾲᕈߦఝࠇߚ
α–Al2O3 ߥߤߩᜂ૕ߦ㧘Ni ࠍᜂᜬߒߚ⸅ᇦ߇↪޿ࠄࠇߡ․ߦᜂ૕ലᨐߦߟ޿ߡ⌕⋡ߒ㧘ߎࠇ߹ߢߦႎ๔଀ߩዋߥ

1,2޿ࠆ‫ޕ‬὇ൻ᳓⚛ߩ᳓⫳᳇ᡷ⾰෻ᔕߦࠃࠆ᳓⚛⵾ㅧᴺߪ㧘

1930 ᐕઍߦߪࠕࡔ࡝ࠞߩ Standard Oil of New Jersey ߢᄤὼࠟࠬ߆ࠄߩ᳓⚛⵾ㅧᴺߣߒߡᦨೋߦⵝ⟎߇૞ࠄࠇࠆߥ
ߤ㧘ฎߊ߆ࠄ⎇ⓥ㐿⊒߇ⴕߥࠊࠇߡ߅ࠅ㧘Ꮏᬺ⊛ߦߪᣢ1ߦቢᚑߐࠇߚ㗔ၞߢ޽ࠆߣ߽⸒ࠊࠇࠆ ‫ޕ‬*1ᚑくᄢቇℂᎿቇㇱ‛⾰↢๮ℂᎿቇ⑼ഥᢎ
(urasaki@st.seikei.ac.jp)
Assistant Processor, Dept. of Materials and Life Science޿㧘ฦ⒳ࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ࠍᜂ૕ߣߒߚ Ni ⸅ᇦߦߟ޿ߡᬌ⸛ߒߡ߈ߚ‫ޕ‬ᓥ᧪㧘ࡔ࠲ࡦߩ᳓⫳᳇ᡷ⾰෻ᔕߢߪ㧘㊄ዻ Ni ߇ᵴᕈὐߢ޽ࠅ㧘Fig. 1(a)ߦ␜ߔࠃ߁ߦ㧘㊄

ዻ Ni ਄ߦࡔ࠲ࡦ߇⸃㔌ๆ⌕ߒߡ↢ᚑߒߚ CHx ⒳߇㊄ዻNi ਄޽ࠆ޿ߪᜂ૕਄ߢᵴᕈൻߐࠇߚ᳓ಽሶߣ෻ᔕߒߡ㧘CO ߇↢ᚑߔࠆߎߣ߇⍮ࠄࠇߡ޿ࠆ‫৻ޕ‬ᣇߢ⪺⠪ࠄ߇ᬌ⸛ࠍⴕߞߡ߈ߚࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ࠍᜂ૕ߣߒߚ႐㧙㧙(a)ว㧘޽ࠆ⒳ߩࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ߩਛߦߪ㧘ਛ㜞᷷CO, CO2CH4ߦ߅޿ߡ㧘⚿᥏᭴ㅧࠍ⛽ᜬߒߚ߹߹㧘㉄ൻ‛ਛߩ㉄⚛ࠕCHx࠾ࠝࡦ㧔ᩰሶ㉄⚛㧕ࠍ᡼಴ߒߡ㉄⚛ⓨሹࠍ↢ᚑߔࠆߎߣ
߇ߢ߈ࠆ߽ߩ߇޽ࠅ㧘Fig. 1(b)ߦ␜ߔࠃ߁ߦ㧘ߎߩࡍࡠࡉCcokeࠬࠞࠗ࠻ᜂ૕ਛߩᩰሶ㉄⚛ࠍ㧘㊄ዻ Ni ਄ߩ CHx ⒳ߩ㉄(b)ࠗ࠻ᜂ૕ਛ߆ࠄᄬࠊࠇߚᩰሶ㉄⚛ࠍ᳓߆ࠄౣ↢ߔࠆࠨࠗ

CHxH2Niࠢ࡞߇ㅴⴕߔࠇ߫㧘ቯᏱ⊛ߦᜂ૕ਛߩᩰሶ㉄⚛ࠍ෻ᔕߦ

CH4CHxNi

supportCO, CO2߹ߚ㧘CHx ⒳߿ᨆ಴὇⚛ߩ㉄ൻߦ೑↪ߐࠇ㧘ࡍࡠࡉࠬࠞ

H2OONiൻ߅ࠃ߮ᨆ಴὇⚛ߩ㉄ൻ㒰෰ߦ೑↪ߔࠆߎߣߢ㧘ᵴᕈߩะ਄޽ࠆ޿ߪ⠴὇⚛ᨆ಴቟ቯᕈߩะ਄߇ᦼᓙߢ߈ࠆ 3,4‫ޕ‬

OCO, CO2

H2O

2-O2-O2O2-O2- O2-O2- O
O2-O2-O2-೑↪ߢ߈ࠆ‫࠻ࠗࠞࠬࡉࡠࡍߥ߁ࠃߩߎޕ‬ᜂ૕ߩലᨐߪ㧘perovskiteࡔ࠲ࡦ᳓⫳᳇ᡷ⾰෻ᔕએᄖߦ߽㧘ࡃࠗࠝࠛ࠲ࡁ࡯࡞߿࠻
࡞ࠛࡦߩ᳓⫳᳇ᡷ⾰෻ᔕ߿᳓ᕈࠟࠬࠪࡈ࠻෻ᔕߥߤߦ߽ㆡ↪ߢ߈ࠆߎߣࠍ⪺⠪ࠄߪ⷗಴ߒߡ޿ࠆ 5-7 ߇㧘ᧄⓂߢߪ㧘ㄭᐕߩ⪺⠪ߩࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ࠍ↪޿ߚࡔ࠲ࡦ᳓(KI  4GCEVKQP UEJGOG QH OGVJCPG UVGCOTGHQTOKPI QXGT PKEMGN ECVCN[UVU UWRRQTVGF QP
CNWOKPCCPFRGTQXUMKVGV[RGQZKFGU⫳᳇ᡷ⾰⸅ᇦߦߟ޿ߡߩ⎇ⓥᚑᨐߦߟ޿ߡ⚫੺ߔࠆ‫ޕ‬
10 0㧞㧚ࡔ࠲ࡦ᳓⫳᳇ᡷ⾰෻ᔕߦ߅ߌࠆ Ni/perovskite

80
CH conversion / %⸅ᇦߩᵴᕈߣ⠴὇⚛ᨆ಴቟ቯᕈߩᬌ⸛ ࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ᜂ૕ߣߒߡ㧘ࠢࠛࡦ㉄㍲૕㊀404วᴺߦߡ⺞⵾ߒߚ LaAlO3㧘LaFeO3㧘La0.4Ba0.6Fe0.2Co0.8O3-δ60

߅ࠃ߮࿕⋧ᴺߦߡ⺞⵾ߒߚ SrTiO3㧘BaTiO3 ࠍ↪޿㧘฽ᶐ20ᴺߦࠃࠅ㧘Ni ࠍ 10 wt%ᜂᜬߒߚ⸅ᇦࠍ⺞⵾ߒ㧘࿕ቯᐥᏱ࿶ᵹㅢᑼ෻ᔕⵝ⟎ࠍ↪޿㧘෻ᔕ᷷ᐲ 1073 K㧘᳓/ࡔ࠲ࡦ0Ყ 2 mol mol-1 ߩ᧦ઙߢࡔ࠲ࡦ᳓⫳᳇ᡷ⾰෻ᔕࠍⴕߞߚ‫ޕ‬

01Ni/perovskite ⸅ᇦ߅ࠃ߮ෳᾖ↪ߦ Ni/α-Al2O3 ࠍ↪޿ߚߣ߈ߩࡔ࠲ࡦォൻ₸ߩ⚻ᤨᄌൻࠍ Fig. 2 ߦ␜ߔ‫߅ߥޕ‬㧘೨

234
Tim e on stream / hou r

56(KI   %CVCN[VKE CEVKXKVKGU QH UWRRQTVGF 0K
ECVCN[UVU
%CVCN[UV ٤ 0K.C#N1 ‫ ع‬0K5T6K1 ٨ 0K.C(G1 ً 0K$C6K1 ٕ 0K.$%( ٣ 0K࡮#N14GCEVKQPEQPFKVKQPUVGORGTCVWTG
-OQNCT*1%*TCVKQ9(IJOQNಣℂߣߒߡ෻ᔕ೨ߦ᳓⚛ᵹㅢਅ 1073 K ߢ 1 ᤨ㑆ㆶరಣℂ

ࠍⴕߞߚ‫ޕ‬ᜂ૕ߦࠃߞߡᄢ߈ߊᡷ⾰ᵴᕈ߇⇣ߥࠅ㧘
LaAlO3 ߿ SrTiO3 ࠍ ↪ ޿ ߚ ႐ ว 㧘 ෳ ᾖ ↪ ߦ ↪ ޿ ߚNi/ α-Al2O3 ⸅ᇦߣ߶߷ห⒟ᐲߩᵴᕈࠍ␜ߔߎߣ߇ࠊ߆ߞ

ߚ‫৻ޕ‬ᣇߢ㧘LaFeO3 ߪᵴᕈ߇ૐߊ㧘La0.4Ba0.6Fe0.2Co0.8O3-δ߅ࠃ߮ BaTiO3 ߢߪ߶ߣࠎߤᵴᕈࠍ␜ߐߥ߆ߞߚ‫ޕ‬100 ᰴߦ㜞޿ᵴᕈࠍ␜ߒߚ Ni/ LaAlO3 ߅ࠃ߮ Ni/ α-Al2O390
CH4 conveersion / %ࠍ↪޿ߡ㧘᳓/ࡔ࠲ࡦᲧࠍ 1 ߦਅߍ㧘὇⚛ᨆ಴ߩ⿠ߎࠅ߿ߔ޿᧦ઙߢᵴᕈ⹜㛎ࠍⴕ޿㧘⠴὇⚛ᨆ಴቟ቯᕈߩᬌ⸛ࠍⴕߞߚ‫⚿ޕ‬ᨐࠍ Fig. 3 ߦ␜ߔ‫ޕ‬Ni/LaAlO3 ߢߪ㧘෻ᔕ㐿ᆎᓟ 24 ᤨ㑆⚻ㆊߒߡ߽ೋᦼᵴᕈࠍ଻ߞߡ޿ߚߩߦኻߒ㧘Ni/ α-Al2O3 ߢߪ㧘὇⚛ᨆ಴߇ේ࿃ߣ⠨߃ࠄࠇࠆᵴᕈૐਅ

8070
60500߇⷗ࠄࠇ㧘ࡔ࠲ࡦォൻ₸߇ᷫዋߒߚ‫ޕ‬

5101520
Time on stream / h25(KI5VCDKNKVKGUQH0K࡮#N1CPF0K.C#N1
4GCEVKQPEQPFKVKQPUVGORGTCVWTG-OQNCT*1%*TCVKQ9(IJOQN%CVCN[UV٤ 0K.C#N1 ٨ 0K࡮#N1㧙㧙CO2 signal / a.u.


(a)
 (b)
Cαߔࠆ࿁᛬✢ߩߺ߇ᓧࠄࠇ㧘෻ᔕᓟ߅ࠃ߮᳓⚛ㆶరᓟߩ⸅ᇦߢߪ㧘㊄ዻ Ni ߣࡍࡠࡉࠬࠞࠗ࠻ဳ᭴ㅧߦ⿠࿃ߔࠆ࿁᛬✢ߩߺ߇᷹ⷰߐࠇߚ‫ࠄ߆ߣߎߩߎޕ‬㧘ᧄ෻ᔕ᧦ઙߢߪ㧘CαCβࡍࡠࡉࠬࠞࠗ࠻ᜂ૕ߪ᳓⫳᳇ᡷ⾰෻ᔕ߅ࠃ߮᳓⚛ㆶరᓟCγߩ޿ߕࠇߦ߅޿ߡ߽ࡍࡠࡉࠬࠞࠗ࠻ဳ᭴ㅧࠍ⛽ᜬߔࠆߎߣ߇⏕⹺ߐࠇߚ‫ߦࠄߐޕ‬㧘ᵴᕈᚑಽߢ޽ࠆ Ni ߦ㑐ߒߡߪ㧘᳓⚛ㆶరߦࠃࠅోߡߩ NiO ߇ Ni ߦㆶరߐࠇߡ߅ࠅ㧘৻ᣇߢ෻ᔕᓟߩ⸅ᇦߩ XRD ࡄ࠲࡯ࡦ߆ࠄ NiO ߦ⿠࿃ߔࠆ

300 400 500 600 700 800 900 1000
Temperature / K(KI6GORGTCVWTGRTQITCOOGFQZKFCVKQPHQT C
0K.C#N1CPF D 0K࡮#N1CHVGTTGCEVKQPHQT J࿁᛬✢߇᷹ⷰߐࠇߥ߆ߞߚߎߣ߆ࠄ㧘᳓⚛ㆶరಣℂߦࠃߞߡ৻ᣤㆶరߐࠇߡ↢ᚑߒߚ㊄ዻ Ni ߪ෻ᔕਛߦ߽቟ቯߢ޽ࠅ㧘NiO ߦౣ㉄ൻߐࠇߥ޿ߎߣ߇ࠊ߆ߞߚ‫ޕ‬ ᰴߦ Ni/perovskite ⸅ᇦߩ㉄ൻㆶర․ᕈࠍ⺞ߴࠆߚ߼㧘෻ᔕ೨߅ࠃ߮෻ᔕᓟߩ⸅ᇦࠍ↪޿㧘᳓⚛ᵹㅢਅ㧘ቶ᷷߆ ෻ᔕᓟߩ⸅ᇦ਄ߦᨆ಴ߒߚ὇⚛ߩቯᕈ㧘ቯ㊂ಽᨆࠍⴕࠄ 1173 K ߹ߢ᣹᷷ߒߚߣ߈ߩ㊀㊂ᄌൻࠍᾲ㊀㊂ಽᨆⵝ߁ߚ߼㧘෻ᔕᓟߩ⸅ᇦࠍขࠅ಴ߒ㧘㉄⚛ᵹㅢਅቶ᷷߆ࠄ
1173 K ߹ߢ᣹᷷ߒߚߣ߈ߦ↢ᚑߔࠆ CO2 ࠍ⾰㊂ಽᨆེߦ⟎ ߦ ߡ ᷹ ቯ ߔ ࠆ ߎ ߣ ߢ 㧘 Temperature Programmed

㧔TPO㧕᷹ቯࠍⴕߞߚ‫⚿ޕ‬ᨐࠍ Fig. 4 ߦ␜ߔ‫ޕ‬ᵴᕈ߇ૐ߅ࠃ߮ 1073 K ߦߡ 1 h ᳓⚛ㆶరಣℂࠍⴕߞߚᓟ㧘1073 K޿ᣇ߆ࠄ Cα㧘Cβ㧘Cγߣߔࠆ㧕߇⏕⹺ߐࠇߚ߇㧘Ni/LaAlO3

ࠍⴕߞߚ⚿ᨐࠍ Fig. 5 ߦ␜ߔ‫ޕ‬෻ᔕ೨ߩ⸅ᇦࠍ↪޿ߡߩߺ↢ᚑߒߚ㧘㜞᷷ߢΆ὾ߔࠆ Cβ㧘Cγߪ㧘෻ᔕᕈ߇ૐ

ߐࠇߚ‫ߪࠇߎޕ‬㧘NiO ߩㆶరߦ⿠࿃ߔࠆ߽ߩߢ޽ࠆ߇㧘ࠃࠅᬌ಴ߔࠆߎߣߢ㧘Temperature Programmed Oxidation

Reduction(TPR)᷹ቯࠍⴕߞߚ‫ޕ‬෻ᔕ೨ᓟߩ Ni/SrTiO3 ⸅ᇦਅߒߚ Ni/ α-Al2O3 ߢߪ 3 ⒳ߩᨆ಴὇⚛⒳㧔Ά὾᷷ᐲߩૐ

ߦߡ 1 h ᳓⫳᳇ߦធ⸅ߐߖߚ Ni/SrTiO3 ⸅ᇦߩ TPR ᷹ቯߢߪ Cαߩߺ߇↢ᚑߔࠆߎߣ߇ಽ߆ߞߚ‫ޕ‬Ni/ α-Al2O3 ߢTPR ᷹ቯࠍⴕ߁ߣ㧘550 K ઃㄭߦᄢ߈ߥ㊀㊂ᷫዋ߇⏕⹺ߔߴߡߩ NiO ߇ Ni ߦㆶరߐࠇࠆߣ߈ߩ㊀㊂ᷫዋ㊂ 26.5ߊ㧘᳓⫳᳇ߦࠃࠆ㒰෰߇࿎㔍ߢ޽ࠆߎߣ߇੍ᗐߐࠇࠆߎmg g-cat-1 ࠃࠅ߽ᄢ߈߆ߞߚ‫ߪࠇߎޕ‬㧘NiO ߣหᤨߦࡍࡠߣ߆ࠄ㧘෻ᔕਛߦ⸅ᇦ⴫㕙ߦ⫾Ⓧߒߡᵴᕈὐߢ޽ࠆ㊄ዻNi ࠍⷒ޿㧘ᵴᕈૐਅߩේ࿃ߣߥߞߚߣ⠨߃ࠄࠇࠆ‫৻ޕ‬ᣇࡉࠬࠞࠗ࠻ᜂ૕߽ㆶరߐࠇߚߎߣࠍ␜ߒߡ޿ࠆ‫ޕ‬XRD ᷹ߢ㧘Ni/LaAlO3 ߢߪ෻ᔕᕈߩૐ޿㧘Cβ㧘Cγߩ↢ᚑ߇ᛥ೙ቯߩ⚿ᨐ߆ࠄ㧘᳓⚛ㆶరᓟߦ߅޿ߡ߽ᜂ૕ߪࡍࡠࡉࠬࠞࠗ࠻ဳ᭴ㅧࠍ⛽ᜬߒߡ޿ߚߎߣ߆ࠄ㧘᳓⚛ㆶరಣℂߦࠃߐࠇ㧘㜞޿቟ቯᕈࠍ␜ߒߚ߇㧘ߎࠇߪࡍࡠࡉࠬࠞࠗ࠻ᜂ
ࠅ㧘ࡍࡠࡉࠬࠞࠗ࠻ᜂ૕ਛߩᩰሶ㉄⚛߇᡼಴ߐࠇ㧘㉄⚛
૕ਛߩᩰሶ㉄⚛ߦࠃࠅ㧘Cβ㧘Cγߩ㉄ൻ߇ଦㅴߐࠇ㧘⫾Ⓧߔࠆߩࠍ㒐޿ߛߚ߼ߢ޽ࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬Ni/LaAlO3 ਄ⓨሹ߇↢ߓࠆߎߣ߇⏕⹺ߐࠇߚ‫ޕ‬Ყߴ㧘⚂ 50 K ૐ޿ߎߣ߆ࠄ߽㧘LaAlO3 ਛߩᩰሶ㉄⚛ߦ߿ߪࠅ㊀㊂ᷫዋ߇⏕⹺ߐࠇߚ‫ޕ‬XRD ᷹ቯߩ⚿ᨐ߆ࠄ෻ᔕ ᰴߦ㧘෻ᔕᓟߩ⸅ᇦࠍ↪޿ߚ TPR ᷹ቯࠍⴕߞߚߣߎࠈ㧘ߦ↢ᚑߔࠆ CαߩΆ὾ࡇ࡯᷷ࠢᐲ߇ Ni/ α-Al2O3 ߩ႐วߣਛߦ㧘᳓⚛ㆶరಣℂߦࠃࠅ↢ߓߚ㊄ዻ Ni ߪ㧘෻ᔕਛߦౣ

ࠃࠅ㧘⸅ᇦ⴫㕙ߦᨆ಴ߒߚ὇⚛ߩ㉄ൻ߇ଦㅴߐࠇࠆߎߣ߇␜ໂߐࠇࠆ‫ ߚ߹ޕ‬TPO ᷹ቯߩ⚿ᨐࠃࠅ㧘὇⚛ᨆ಴㊂ߪ㧘Ni/ α-Al2O3 ߢߪ 3.96 mg g-cat ߢ޽ ߞߚߩ ߦ ኻߒ㧘-1㉄ൻߐࠇߕ㊄ዻ Ni ߩ⁁ᘒࠍ⛽ᜬߔࠆߎߣ߇ࠊ߆ߞߡ޿
ࠆߚ߼㧘ߎߩ㊀㊂ᷫዋߪᜂ૕߇ㆶరߐࠇ㧘ᩰሶ㉄⚛ࠍ᡼

Ni/LaAlO3 ߢߪ 3.32 mg g-cat-1 ߣ߿߿ዋߥ߆ߞߚ‫ޕ‬಴ߒߚߎߣߦ⿠࿃ߔࠆ߽ߩߢ޽ࠆ‫ޕ‬ᓥߞߡ㧘೨ಣℂߣߒ એ਄ߩ⚿ᨐࠃࠅ LaAlO3 ߿ SrTiO3 ߥߤߩࡍࡠࡉࠬࠞࠗ
Weight loss g g-cat-1

࠻ဳ㉄ൻ‛ࠍ Ni ⸅ᇦᜂ૕ߦㆡ↪ߔࠆߎߣߢ㧘Ყセ⊛㜞޿ᵴᕈࠍ␜ߔߣหᤨߦ㜞޿⠴὇⚛ᨆ಴቟ቯᕈࠍ᦭ߔࠆ⸅ᇦ
߇ᓧࠄࠇࠆߎߣ߇ಽ߆ߞߚ‫ޕ‬

㧟㧚0KRGTQXUMKVG ⸅ᇦߩ㉄ൻㆶర․ᕈߩᬌ⸛ ࡍࡠࡉࠬࠞࠗ࠻ဳ㉄ൻ‛ᜂ૕ߣߒߡ LaAlO3㧘SrTiO3㧘
BaTiO3 ࠍ↪޿ߚ Ni ⸅ᇦߦߟ޿ߡ㧘෻ᔕ೨ᓟ߅ࠃ߮᳓⚛

0(a)
-0.02
-0.04
-0.06
(b)
Weight loss
-0.08
-1= 26.5 mg g-cat-0.1-0.12(B)
-0.14
400
600
800
1000 1200
Temperature/ K(KI 624WUKPI6)HQT C WUGFECVCN[UVUCPF D
HTGUJECVCN[UVU%CVCN[UV0K5T6K14GCEVKQP
EQPFKVKQPU-OQNCT*1%*TCVKQㆶరᓟߩ᭴ㅧࠍ⺞ߴࠆߚ߼㧘XRD ᷹ቯࠍⴕߞߚ‫ޕ‬෻ᔕ೨ߩ⸅ᇦߦ߅޿ߡߪ㧘NiO ߣࡍࡠࡉࠬࠞࠗ࠻ဳ᭴ㅧߦ⿠࿃㧙㧙

He flowߡⴕߞߚ᳓⚛ㆶరಣℂߦࠃࠅࡍࡠࡉࠬࠞࠗ࠻ᜂ૕߇ㆶర

CH flow450ߐࠇ㧘ᩰሶ㉄⚛ࠍ᡼಴ߔࠆ߽ߩߩ㧘෻ᔕਛߦ᳓⫳᳇ߦࠃ-1

ߞߡౣ㉄ൻߐࠇߡᩰሶ㉄⚛߇⵬లߐࠇࠆߎߣ߇ࠊ߆ߞߚ‫ޕ‬O consumption rate / mmol min߹ߚ㧘޿ߕࠇߩ Ni/perovskite ⸅ᇦߦ߅޿ߡ߽㧘෻ᔕᓟߩ⸅ᇦ߆ࠄ᡼಴ߐࠇࠆᩰሶ㉄⚛㊂ߪ㧘෻ᔕ೨ߩ⸅ᇦ߆ࠄ᡼಴ߐࠇࠆᩰሶ㉄⚛㊂ߣᲧߴߡዋߥ߆ߞߚ‫ࠄ߆ߣߎߩߎޕ‬㧘෻ᔕ႐ߦ߅޿ߡ᳓⚛ㆶరಣℂߦࠃࠅ᡼಴ߐࠇߚᩰሶ㉄⚛
ߩ⵬లߛߌߢߥߊᶖ⾌߽ⴕࠊࠇߡ޿ࠆߎߣ߇ផ᷹ߐࠇࠆ‫ޕ‬ߎߩ෻ᔕਛߦᶖ⾌ߐࠇߡ޿ࠆߣ⠨߃ࠄࠇࠆᩰሶ㉄⚛ߪ㧘

Ni/SrTiO330
Ni/LaAlO320

Ni/BaTiO3102-㊄ዻ Ni ߦ⸃㔌ๆ⌕ߒߚ CHx ߩ㉄ൻ߅ࠃ߮ᨆ಴὇⚛ߩ㒰40෰ߦ೑↪ߐࠇߚ߽ߩߣ⠨߃ࠄࠇࠆ‫ޕ‬ ᦨᓟߦ㧘Ni/SrTiO3 ⸅ᇦࠍㆶరᓟ㧘᳓⫳᳇ߦធ⸅ߐߖߚ00⸅ᇦߦߟ޿ߡ TPR ᷹ቯࠍⴕߞߚ႐ว߽㊀㊂ᷫዋ߇⷗ࠄ246Time on stream / minࠇߚ‫⸅ߩߎޕ‬ᇦࠍ XRD ߦߡ᷹ቯߒߚߣߎࠈ㧘㊄ዻ Ni ߪ(KI  #OQWPVU QH EQPUWOGF NCVVKEG QZ[IGP
4GCEVKQPEQPFKVKQPU-OQNCT*1%*TCVKQ⷗ࠄࠇߕ㧘NiO ߩ↢ᚑ߇⏕⹺ߐࠇߚߎߣ㧘㊀㊂ᷫዋ㊂߇NiO ߇㊄ዻ Ni ߦㆶరߐࠇࠆߣ߈ߩ㊀㊂ᷫዋ㊂ 26.5 mg

g-cat-1 ߣ߶߷╬ߒ߆ߞߚߎߣ߆ࠄ㧘᳓⚛ㆶరಣℂࠍⴕߞߚ Ni/SrTiO3 ࠍ᳓⫳᳇ߣធ⸅ߐߖߡ߽㊄ዻ Ni ߩ㉄ൻߩߺ߇ㅴⴕߒ㧘ᜂ૕ߩౣ㉄ൻߦࠃࠆᩰሶ㉄⚛ߩౣ⵬లߪⴕࠊࠇߥ޿ߎߣ߇ࠊ߆ߞߚ‫߼ߚߩߘޕ‬㧘᳓߆ࠄߩᩰሶ㉄⚛ߩ⵬లߦߪ㧘㊄ዻ Ni ߇ᔅⷐߢ޽ࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬8ࠄ▚಴ߒߚ㧘ᩰሶ㉄⚛ߩᶖ⾌ㅦᐲߩ⚻ᤨᄌൻࠍ Fig. 6 ߦ␜ߔ‫ߚ߹ޕ‬㧘ࡔ࠲ࡦ㉄ൻߦ೑↪ߐࠇߚᩰሶ㉄⚛㊂ࠍห෻ᔕ᧦ઙߦߡ෻ᔕࠍⴕߥߞߚᓟߩ Ni/perovskite ⸅ᇦࠍ↪޿ߡ TPR ᷹ቯࠍⴕߥ޿㧘෻ᔕਛߦౣ↢ߐࠇߚᩰሶ㉄⚛㊂ࠍ᷹ቯߒߚ⚿ᨐߣᲧセߒߚ⚿ᨐࠍ Table 1 ߦ␜ߔ‫ߩࠇߕ޿ޕ‬ એ਄ߩ⚿ᨐ߆ࠄ㧘೨ಣℂߣߒߡⴕ߁᳓⚛ㆶరߦࠃࠅ㧘⸅ᇦߦ߅޿ߡ߽ਔ⠪ߩ୯߇ㄭ޿ߎߣ߆ࠄ㧘෻ᔕਛߦౣ↢NiO ߇ Ni ߦㆶరߐࠇࠆߩߣหᤨߦ㧘ࡍࡠࡉࠬࠞࠗ࠻ᜂ૕

ߐࠇࠆᩰሶ㉄⚛ߩ߶߷ో㊂߇ࡔ࠲ࡦߩ㉄ൻߦ೑↪ߐࠇߚ߽ㆶరߐࠇ㧘ᩰሶ㉄⚛ࠍ᡼಴ߒ㧘ߘߩᓟ෻ᔕ႐ߦ߅޿ߡ㧘ߎߣ߇ࠊ߆ߞߚ‫ޕ‬᳓⚛ߦࠃࠅㆶరߐࠇߚࡍࡠࡉࠬࠞࠗ࠻ᜂ૕߇᳓⫳᳇ߦࠃࠅౣ㉄ൻߐࠇ㧘ᩰሶ㉄⚛߇ౣ↢ߐࠇࠆߎߣ߇ಽ߆ߞߚ‫ޕ‬

6CDNG  #OQWPVU QH EQPUWOGF NCVVKEG QZ[IGP KP
RGTQXUMKVGU߹ߚ㧘᳓⚛ㆶరߦࠃࠅ᡼಴ߐࠇߚᩰሶ㉄⚛ߩోߡߢߪߥߊ㧘৻ㇱߩߺ߇ౣ↢ߐࠇߡ޿ߚߎߣ߆ࠄ㧘෻ᔕ႐ߦ߅޿



Catalystߡ᳓⫳᳇߆ࠄౣ↢ߐࠇߚᩰሶ㉄⚛߇෻ᔕߦ೑↪ߐࠇߚߣ
Ni/LaAlO3
Ni/SrTiO3
Ni/BaTiO3⠨߃ࠄࠇࠆ‫ޕ‬㧠㧚ᩰሶ㉄⚛ߩ෻ᔕᕈaConsumed lattice oxygen/ mg g-cat-1
7.4
12.1
23.5

∆WLa/ mg g-cat-1
8.4
14.5
22.3

Amounts of lattice oxygen released from catalysts used

after reaction at 923 K during TPR experiment.

Reaction conditions; 923 K; molar H2O/CH4 ratio, 2.

 ࡍࡠࡉࠬࠞࠗ࠻ᜂ૕ਛߩᩰሶ㉄⚛ߩ෻ᔕᕈࠍᬌ⸛ߔࠆߚ߼㧘ᩰሶ㉄⚛ߦࠃࠆࡔ࠲ࡦ㉄ൻታ㛎ࠍⴕߞߚ‫ߕ߹ޕ‬㧘Ni/perovskite ⸅ᇦߣߒߡ Ni/LaAlO3㧘Ni/SrTiO3㧘Ni/BaTiO3

㧡㧚෻ᔕࡕ࠺࡞

ᔕ᷷ᐲ 923 K ߢ෻ᔕࠍⴕ޿㧘ߘߩᓟห෻ᔕ᷷ᐲߦߡࡋ࡝ ߎࠇ߹ߢߦᓧࠄࠇߚ⚿ᨐ߆ࠄ㧘Fig. 7 ߦ Ni/perovskiteࠍ↪޿㧘1073 K ߦߡ 1 h ᳓⚛ㆶరಣℂࠍⴕߥߞߚᓟ㧘෻
࠙ࡓߢ 30 min ࡄ࡯ࠫࠍⴕߥߞߚᓟߦ㧘ࡔ࠲ࡦߩߺࠍଏ⛎

⸅ᇦߦࠃࠆࡔ࠲ࡦߩ᳓⫳᳇ᡷ⾰෻ᔕߩࡕ࠺࡞࿑ࠍ␜ߔ‫ޕ‬ߒ㧘ᩰሶ㉄⚛ߩߺߦࠃࠆࡔ࠲ࡦ㉄ൻታ㛎ࠍⴕߥߞߚ‫↢ޕ‬᳓⚛ㆶరߦࠃࠅ㧘NiO ߇ㆶరߐࠇࠆߩߣหᤨߦ㧘ᜂ૕߽ᚑࠟࠬߩቯᕈቯ㊂ಽᨆߪ㧘྾㊀ᭂ⾰㊂ಽᨆེࠍ↪޿ߚ‫ޕ‬ㆶరߐࠇߡᩰሶ㉄⚛߇᡼಴ߒ㧘ᩰሶᰳ㒱ࠍ↢ߓࠆ߇㧘㊄޿ߕࠇߩ Ni/perovskite ⸅ᇦߦ߅޿ߡ߽෻ᔕᓟߩ⸅ᇦߦࡔ

ዻ Ni ߇ሽ࿷ߔࠆ႐ว㧘ߎࠇࠄߩᩰሶ㉄⚛ߪ෻ᔕਛߦౣ↢࠲ࡦࠍଏ⛎ߒߚߣߎࠈ㧘ࡔ࠲ࡦ߇㉄ൻߐࠇ㧘CO㧘CO2ߐࠇ㧘Ni ߣࡍࡠࡉࠬࠞࠗ࠻ᜂ૕ߩ⇇㕙ߦ߅޿ߡ㧘ࡔ࠲ࡦ߇↢ᚑߒߚ‫ࠄ߆ߣߎߩߎޕ‬㧘ᩰሶ㉄⚛ߦࠃࠆࡔ࠲ࡦߩ㉄ൻ෻ᔕ߇ㅴⴕߔࠆߎߣ߇ࠊ߆ߞߚ‫ޕ‬CO㧘CO2 ߩ↢ᚑ㊂߆߇ Ni ਄ߦ⸃㔌ๆ⌕ߒߡ↢ᚑߒߚ CHx ⒳ߣߩ෻ᔕߦ೑↪
ߐࠇࠆߣ⠨ኤߒߚ‫ߥ߁ࠃߩߎޕ‬ᩰሶ㉄⚛ߦࠃࠆ Ni ਄ߦ↢㧙㧙

H2 reduction

NiO

O2- O2- O2-Perovskite

CH4defect
Ni

Perovskite
COCH4/H2O

CHx
NiPerovskite

Oad

H2O

O2- O2- O2-(KI  2TQRQUGF TGCEVKQP OGEJCPKUO HQT UVGCOTGHQTOKPIQHOGVJCPGQXGT0KRGTQXUMKVG
ᚑߒߚ CHx ⒳ߩ㉄ൻଦㅴലᨐߦࠃߞߡ㧘Ni/perovskite ⸅ᇦߩ㜞޿⠴὇⚛ᨆ಴቟ቯᕈ߇ᓧࠄࠇߚ߽ߩߣ⠨߃ࠄࠇࠆ‫ޕ‬㧢㧚⻢ ㄉ ᧄ⺰ಽߪ⪺⠪߇ᣧⒷ↰ᄢቇℂᎿቇㇱߦ࿷☋ᤨߦ⊒⴫ߒߚ⎇ⓥᚑᨐࠍ߹ߣ߼ߚ߽ߩߢ޽ࠅ㧘ᣧⒷ↰ᄢቇ⩵࿾⧷৻ᢎ᝼㧘᧻ᣇᱜᒾᢎ᝼㧘㑐ᩮᵏḰᢎ᝼෸߮㑐ଥ⠪ߦᗵ⻢޿ߚߒ߹ߔ‫ޕ‬ෳ⠨ᢥ₂
1. J. R. Rostrup-Nielsen, Catalytic steam reforming,

in: J. R. Andersen, M. Boudart (Eds.), Catalysis,
Science and Technology, Vol. 5, Springer, Berlin,䋨1983䋩 p. 1.

2. J. R. Rostrup-Nielsen, J–H. B. Hansen, L. M.
Aparicio, Sekiyu Gakkaishi, 40 (1997) 366.

3. K. Urasaki, Y. Sekine, S. Kawabe, E. Kikuchi, M.
Matsukata, Appl. Catal. A., 286 (2005) 23-29.

4. ᶆፒ ᶈᐔ䋬દ⮮ ੝♿ሶ䋬㑐ᩮ ᵏ䋬⩵࿾ ⧷৻䋬᧻ᣇᱜᒾ䋬⸅ᇦ, 47 (2005) 409䋮5. K. Urasaki, Y. Fukuda, Y. Sekine, M. Matsukata, E.
Kikuchi, J. Jpn. Petrol. Inst., 51 (2008) 83.

6. K. Urasaki, K. Tokunaga, Y. Sekine, E. Kikuchi, M.
Matsukata, Chem. Lett., 34 (2005) 668.

7. ᶆፒ ᶈᐔ䋬⍹Ꮉ ᷡብ䋬㑐ᩮ ᵏ䋬⩵࿾ ⧷৻䋬᧻ᣇ ᱜᒾ䋬⸅ᇦ䋬48 (2006) 65䋮㧙㧙