1P019ࡺࡽࡂ࠿ࡽࡳࡓ㉸⮫⏺ CO2-CH3OH ΰྜ⣔ࡢᵓ㐀( ༓ⴥ኱Ꮫ኱Ꮫ㝔⼥ྜ⛉Ꮫ◊✲⛉ ) ‫ۑ‬ຍ℩㥴௓ࠊ⏣୰Ⰻᛅࠊすᕝ᝴Ꮚ࠙⥴ゝࠚ  ༢ᡂศ⣔࡟࠾ࡅࡿẼᾮඹᏑ⥺࡟ࡣࠊ㧗 㧗ᅽഃ࡟⤊Ⅼࡀ࠶ࡾࠊࡇࡢ⤊Ⅼࢆ⮫⏺Ⅼ࡜࿧ࡪࠋ⮫⏺Ⅼࡼࡾࡶ㧗 㧗ᅽഃ࡟࠶ࡿ≧ែࢆ㉸⮫⏺≧ែ࡜࿧ࡧࠊᵝࠎ࡞≉ᚩⓗ≀ᛶࢆ♧ࡍࡇ࡜࠿ࡽࠊᇶ♏◊✲ࡣࡶ࡜ࡼࡾከᵝ࡞ᛂ⏝ࡀ࡞ࡉࢀ࡚࠸ࡿࠋ  ᡃࠎࡢ◊✲ᐊ࡛ࡣࠊ㉸⮫⏺ὶయࢆ≉ᚩ௜ࡅࡿࣃ࣓࣮ࣛࢱ࣮࡜ࡋ࡚”ࡺࡽࡂ”ࢆ᥇⏝ࡋࠊ༢ᡂศ⣔࡟ࡘ࠸࡚ࡣࠊࡺࡽࡂ࡜≀ᛶ࡜ࡢ㛵ಀࢆ᫂ࡽ࠿࡟ࡋ࡚ࡁࡓ 1)ࠋ௒ᅇࡣࠊ㉸⮫⏺ὶయ࡟ᑡ㔞ࡢῧຍ≀ࢆຍ࠼ࡿ࡜≉ᐃࡢ≀㉁࡟ᑐࡍࡿ⁐ゎᗘࡀኚ໬ࡍࡿ࢚ࣥࢺ࣮ࣞࢼ࣮ຠᯝ 2)࡟╔┠ࡋࠊࡺࡽࡂࡢほⅬ࠿ࡽㄪ࡭࡚ࡳࡿࡇ࡜࡟ࡋࡓࠋ  ࡇࡇ࡛ࡢ“ࡺࡽࡂ”࡜ࡣࠊᐦᗘࡺࡽࡂ SNN ࡜⃰ᗘࡺࡽࡂ SCC ࢆᣦࡍࠋᐦᗘࡺࡽࡂࡣࠊศᏊศᕸࡢ୙ᆒ୍ࡉࢆ཯ᫎࡋࡓ≀⌮㔞࡛࠶ࡾࠊศᏊࡀᆒ୍࡟ศᩓࡋ࡚࠸ࢀࡤᑠࡉ࡞್ࢆࠊศᏊ㞟ྜయࡢᙧᡂ࡞࡝࡟ࡼࡗ࡚ศᏊศᕸ࡟୙ᆒ୍ࡀ⏕ࡌࡿ࡜኱ࡁ࡞್ࢆ࡜ࡿࠋ୍᪉ࠊ⃰ᗘࡺࡽࡂࡣࠊ஧ᡂศ
⣔࡛ᐃ⩏ࡉࢀࠊΰྜ≧ែࡢ୙ᆒ୍ࡉࢆᣦࡋ♧ࡍ≀⌮㔞࡛࠶ࡿࠋ஧✀ࡢศᏊࡀ஫࠸࡟ධࡾΰࡌࡗ
࡚࠸ࢀࡤ⃰ᗘࡺࡽࡂࡣᑠࡉࡃ࡞ࡾࠊ㏫࡟ࠊྠ୍ศᏊࡔࡅ࡛㞟ࡲࡿࡼ࠺࡞ΰྜ≧ែࢆ࡜ࡿሙྜࡣ⃰ᗘࡺࡽࡂࡀ኱ࡁࡃ࡞ࡿࠋࡲࡓࠊ஧ᡂศ⣔࡟࠾ࡅࡿࡇࢀࡽᦂࡽࡂࡣ➼ ᅽ⦰⋡ࠊ㒊ศࣔࣝయ✚n ࠾ࡼࡧᑠゅ X ⥺ᩓ஘ᙉᗘ࠿ࡽồࡵࡿࡇ࡜ࡀ࡛ࡁࡿࠋࡉࡽ࡟ࠊΰྜ⣔ࡢᐦᗘࡺࡽࡂ࣭⃰ᗘࡺࡽࡂ࠿ࡽ Kirkwood-Buff ࡢࣃ࣓࣮ࣛࢱ࣮3)ࢆồࡵࡿࡇ࡜࡛ࠊΰྜ⣔࡟࠾ࡅࡿᡂศࡢᐦᗘࡺࡽࡂ 4)ࢆศ㞳ࡍࡿࡇ࡜ࡀ࡛ࡁࡿࠋඛ㏙ࡋࡓΰྜ⣔ࡢᐦᗘࡺࡽࡂࡣࠊ஧ᡂศ⣔࡟࠾ࡅࡿ୧ᡂศࡢศᏊศᕸࢆ཯ᫎࡋ࡚࠸ࡿࡓࡵࠊᡂศࡢᣲືࢆ▱ࡿࡇ࡜ࡣ࡛ࡁ࡞࠸ࡀࠊࡇ࠺ࡋ࡚ᡂศ࡬࡜ศ㞳ࡍࡿࡇ࡜࡛ࠊΰྜ⣔࡟࠾ࡅࡿྛᡂศࡢศᏊศᕸࢆホ౯ࡍࡿࡇ࡜ࡀ࡛ࡁࡿࠋ࠙ᐇ㦂ࠚ  ᑐ㇟࡜ࡍࡿࢧࣥࣉࣝࡣࠊᕤᴗⓗ࡞ᛂ⏝ࡀ࡞ࡉࢀ࡚࠸ࡿ㉸⮫⏺ CO2 ࢆ࣮࣋ࢫ࡜ࡋࠊࡇࢀ࡟ᑐࡋ
࡚ CH3OH ࢆ 5% (w/w)⛬ᗘຍ࠼ࡓΰྜ⣔ࢆ㑅ࢇࡔࠋࡇࡢΰྜ⣔ࡣࢡ࣐ࣟࢺࢢࣛࣇ࢕࣮ࡸࠊᢳฟࡢศ㔝࡛ᐇ㝿࡟฼⏝ࡉࢀ࡚࠸ࡿࠋᐇ㦂᮲௳࡜ࡋ࡚ࡣࠊCH3OH 5%࡟ᙜࡓࡿࣔࣝศ⋡ xCO2 = 0.93ࠊᗘࡣ⮫⏺ ᗘࡼࡾ 4%㧗࠸ 321.8 Kࠊᅽຊ⠊ᅖࡣ 9 - 15MPa ࡜ࡋࡓࠋ80
SNNSCC-100
CO2CH3OH-200
-300
0.4

0.5
0.6
0.7
0.8
-3
Density / g cm
Fig. 1 Partial molar volume vs. density

Fluctuation

03n / cm mol

-1

10060
40
20
00.4

0.5

0.6

0.7

0.8

-3

Density / g cm
Fig. 2 Fluctuations of mixture vs. density௨ୖࡢ⣔࡟ᑐࡋ࡚ᑠゅ X ⥺ᩓ஘ ᐃ࠾ࡼࡧᐦᗘ ᐃࢆ⾜ࡗࡓࠋX ⥺ᩓ஘ ᐃࡣࠊᨺᑕගඹྠ฼⏝᪋タ Photon Factory ෆࡢ BL-15A ࡟࡚⾜࠸ࠊἼ㛗ࡣ l = 0.150 nmࠊ ᐃࡋࡓゅᗘ⠊ᅖࡣᩓ஘ࣃ࣓࣮ࣛࢱ࣮ s = 4p sinq / l࡛ 0.2 - 2 nm-1 ࡛࠶ࡿࠋᐦᗘ ᐃࡣᡃࠎࡢ◊✲ᐊ࡟࡚᣺ື⟶ᘧᐦᗘィࢆ⏝࠸࡚⾜ࡗࡓࠋᐦᗘࡢᅽຊᚤศࡼࡾ➼ ᅽ⦰⋡ࢆồࡵࡓࠋ୪⾜ࡋ࡚ࠊྠࡌ ᗘࠊᅽຊ⠊ᅖ࡟࠾࠸࡚ xCO2 = 0.90 , 0.95 ࡟ࡘ࠸࡚ࡶᐦᗘ ᐃࢆ⾜࠸ࠊᐦᗘࡢ⃰ᗘᚤศࡼࡾ CO2 ࡜ CH3OHࡢ㒊ศࣔࣝయ✚n ࢆࡑࢀࡒࢀồࡵࡓࠋ௨ୖࡢ⤖ᯝ࠿ࡽΰྜ⣔ࡢᐦᗘࡺࡽࡂ࣭⃰ᗘࡺࡽࡂࢆồࡵࡓࠋḟ࠸࡛ࠊKirkwood-Buff ࡢࣃ࣓࣮ࣛࢱ࣮ࢆ⟬ฟࡋࠊᡂศࡢᐦᗘࡺࡽࡂࢆศ㞳ࡋࡓࠋ࠙⤖ᯝ࡜⪃ᐹࠚ  ᐦᗘ ᐃࡼࡾồࡵࡓ㒊ศࣔࣝయ✚n ࢆ Fig. 1 ࡟♧ࡍࠋ ᐃࡋࡓ⠊ᅖෆ࡛ CH3OH ࡢ㒊ศࣔࣝయ✚ࡀ㈇ࡢ್ࢆ♧ࡋࡓࠋࡇࢀࡣࡇࡢ⠊ᅖෆ࡛ࡣࠊ㉸⮫⏺ CO2-CH3OH ΰྜ⣔࡟ CH3OH ࢆຍ࠼ࡿ࡜⣔ࡢయ✚ࡀῶᑡࡍࡿࡇ࡜ࢆ⾲ࡋࠊCH3OH ࡢจ㞟ࡀᘬࡁ㉳ࡇࡉࢀ࡚࠸ࡿࡇ࡜ࢆព࿡ࡍࡿࠋḟ࡟ࠊᚓࡽࢀࡓ➼ ᅽ⦰⋡࡜㒊ศࣔࣝయ✚࠾ࡼࡧ X ⥺ᩓ஘ᙉᗘ࠿ࡽΰྜ⣔ࡢᐦᗘࡺࡽࡂ࣭⃰ᗘࡺࡽࡂࢆồࡵࡓࠋࡑࡢ⤖ᯝࢆ Fig. 2 ࡟♧ࡍࠋࡲࡓࠊẚ㍑ࡢࡓࡵࠊᙜ◊✲ᐊ࡟ࡼࡗ࡚ᚓࡽࢀࡓྠࡌ᥮⟬ ᗘ Tr = 1.04 ࡟࠾ࡅࡿ௚ࡢ㉸⮫⏺⣔ࡢᐦᗘࡺࡽࡂ࣭⃰ᗘࡺࡽࡂࡢᴟ኱್ࢆ Tab. 1 ࡟♧ࡍࠋ㉸⮫⏺ CO2-CH3OH ΰྜ⣔ࡀ኱ࡁ࡞ᐦᗘࡺࡽࡂࠊ⃰ᗘࡺࡽࡂࢆᣢࡘࡇ࡜ࡀࢃ࠿ࡿࠋࡲࡓࠊ㒊ศࣔࣝయ✚ࡢᴟ್ࢆ୚࠼ࡿᐦᗘ㏆㎶࡛ᐦᗘࡺࡽࡂࡀᴟ್ࢆ࡜ࡗ࡚࠸ࡿࡇ࡜࠿ࡽࠊจ㞟࡟ࡼࡗ࡚ศᏊศᕸ࡟୙ᆒ୍ࡀ⏕ࡌࠊᐦᗘࡺࡽࡂࡀቑຍࡋࡓ࡜⪃࠼ࡿࡇ࡜ࡀ࡛ࡁࡿࠋ

Density fluctuation

120
CO2CH3OH

80
4000.50.6
0.70.8-3Density / g cm
Fig. 3 Fluctuations of components vs. density

Tab. 1 ( Mole ratio in the brackets )Maximum at Tr = 1.04

SNNSCC

CO212-Xe-Kr mixture (0.50:0.50)

170.3

CO2-CHF3 mixture (0.75:0.25)

12

1.5

CO2-CH3OH mixture (0.93:0.07)

64

5.20.4 ࡉࡽ࡟ࠊ௨ୖ࡛ᚓࡽࢀࡓΰྜ⣔ࡢᐦᗘࡺࡽࡂ࣭⃰ᗘࡺࡽࡂࢆ⏝࠸࡚ Kirkwood-Buff ࡢࣃ࣓࣮ࣛࢱ࣮ࢆィ⟬ࡋࠊΰྜ⣔࡟࠾ࡅࡿྛᡂศࡢᐦᗘࡺࡽࡂࢆศ㞳ࡋࡓࠋࡑࡢ⤖ᯝࢆ Fig. 3 ࡟♧ࡍࠋ
Fig. 2 ࠾ࡼࡧ Fig. 3 ࡼࡾࠊCO2 ࡢᐦᗘࡺࡽࡂࡀᴟ኱್ࢆྲྀࡿ㎶ࡾ࡛ΰྜ⣔ࡢᐦᗘࡺࡽࡂࡶᴟ኱
್ࢆ࡜ࡗ࡚࠸ࡿࡇ࡜ࡀࢃ࠿ࡿࠋࡇࢀࡣࠊᡂศẚ࠿ࡽ᫂ࡽ࠿࡞ࡼ࠺࡟ࠊᩘࡢୖ࡛ᅽಽⓗ࡞ CO2 ࡢศᏊศᕸࡢኚ໬ࡀΰྜ⣔඲య࡬࡯࡜ࢇ࡝ᨭ㓄ⓗ࡞ᙳ㡪ࢆ୚࠼࡚࠸ࡿ࡜⪃࠼ࡿࡇ࡜ࡀ࡛ࡁࡿࠋ୍
᪉ CH3OH ࡣ㠀ᖖ࡟኱ࡁ࡞ᐦᗘࡺࡽࡂࢆᣢࡕࠊCH3OH ࡢᐦᗘࡺࡽࡂࡢᴟ኱್ࡢ఩⨨ࡣΰྜ⣔࡟࠾ࡅࡿ⃰ᗘࡺࡽࡂࡢᴟ኱್ࡢ఩⨨࡜኱య୍⮴ࡍࡿࠋ኱ࡁ࡞ᐦᗘࡺࡽࡂࢆࡶࡘࡇ࡜ࡣศᏊศᕸࡢ␯ᐦࡀ኱࡛࠶ࡿࡇ࡜ࢆ♧ࡍࡢ࡛ࠊCH3OH ࡀᒁᡤⓗ࡟㞟ྜࡍࡿࡇ࡜࡟ࡼࡗ࡚⣔඲యࡢ CH3OH ࡜CO2 ࡢΰࡊࡾලྜ࡟୙ᆒ୍ࡀ⏕ࡌࠊ⃰ᗘࡺࡽࡂࡢቑຍࢆࡶࡓࡽࡋࡓ࡜⪃࠼ࡿࡇ࡜ࡀ࡛ࡁࡿࠋࡲ
ࡓࠊ㉸⮫⏺ CO2-CH3OH ΰྜ⣔࡟࠾࠸࡚ CH3OH ศᏊ㛫࡟Ỉ⣲⤖ྜࡀᙧᡂࡉࢀ࡚࠸ࡿ 5)ࡇ࡜ࡀࢃ
࠿ࡗ࡚࠾ࡾࠊ௚ࡢ⣔࡟ẚ࡭࡚ΰྜ⣔ࡢᐦᗘࡺࡽࡂࠊ⃰ᗘࡺࡽࡂ࠾ࡼࡧ CH3OH ᡂศࡢᐦᗘࡺࡽࡂࡀ኱ࡁ࡞್ࢆ♧ࡍࡢࡣࠊỈ⣲⤖ྜ࡟ࡼࡿᙳ㡪ࡀ኱ࡁ࠸࡜⪃࠼ࡽࢀࡿࠋ࠙ཧ⪃ᩥ⊩ࠚ1)
2)
3)
4)
5)

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