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-15 -10 -5 0

-15

-10

-5

0

log [O2]

NaS2

Na2SO4Na2S

Na Na2O

    l   o   g

    [    S    O

          2    ]

2 Na + ½ O2↔ Na2O

2 Na20 + SO2 + ½ O2

↔ Na2SO4

2 NaS + 2 O2

↔ Na2SO4

2 Na + SO2↔

Na2S +O2

Na2S + 3 SO2↔ 2 NaS2 + 3 O2

Na2S + 3/2 O2

↔ Na2O + SO2

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-15 -10 -5 0

glass meltpure phases

Na2SO4

Na2S

NaS2

Na2O

log [O2]

-15 -10 -5 0-15

-10

-5

0

NaS2

Na2SO

4Na

2S

Na Na2O   l  o

  g

   [   S   O

        2   ]

log [O2]

1400 °C

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Na-O-S

„Daumenkino“

„thumbs movie“

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pure phases vs. glass melts

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0

-2

-4

-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 900 °C

Na2O

Na2O2

Na2S2O7

Na2SO4

Na2S

NaS2

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0

-2

-4

-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 900 °C

Na2O

Na2SO4

Na2S

NaS2

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0

-2

-4

-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1500 °C

Na2O

NaS2

Na

Na2SO4

Na2S

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0

-2

-4

-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1500 °C

Na2ONa2S

NaS2

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pure phases, temperature dependence

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0

-2

-4

-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 800 °C

O2-

O22-

S2O72-

SO42-

S2-

S2-

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0

-2

-4

-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 800 °C

Na2O

Na2O2

Na2S2O7

Na2SO4

Na2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 900 °C

Na2O

Na2O2

Na2S2O7

Na2SO4

Na2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1000 °C

Na2O

Na2O2

Na2SO4

Na2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1100 °C

Na2O

Na2SO4

Na2S

NaS2

Na

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1200 °C

Na2O

Na2SO4

Na2S

NaS2

Na

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1300 °C

Na2O

Na2SO4

NaS2

Na

Na2S

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1400 °C

Na2O

Na2SO4

Na2S

NaS2

Na

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1500 °C

Na2O

NaS2

Na

Na2SO4

Na2S

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glass melt, temperature dependence

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 800 °C

Na2O

Na2SO4

Na2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 900 °C

Na2O

Na2SO4

Na2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1000 °C

Na2SO4

Na2ONa2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1100 °C

Na2SO4

Na2O

Na2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o

   g    [    S    O

    2    ]

log [O2]

T = 1200 °C

Na2SO4

Na2O

Na2

S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20

-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o   g    [    S    O

    2    ]

log [O2]

T = 1300 °C

Na2SO4

Na2O

Na2

S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20

-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o   g    [    S    O

    2    ]

log [O2]

T = 1400 °C

Na2ONa2S

NaS2

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0

-2

-4-6

-8

-10

-12-14

-16

-18

-20

-20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0

    l   o   g    [    S    O

    2    ]

log [O2]

T = 1500 °C

Na2ONa2S

NaS2

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log [O2]

log [SO2]

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log [O2]

log [SO2]

l [SO ] T 600 °C l SO d O ti

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-20 -10 0 log [O2]

0

-2

-4

-6

-8

log [SO2]

NiS NiSO4

Ni

T = 600 °C; only SO2 and O2 as reactive gases

Ni3S2 NiO

log [S ] T = 600 °C; SO and O ; log [H O] = 5

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0

-2

-4

-6

-8

log [Stot]

-20 -10 0 log [O2]

NiS NiSO4

Ni

T = 600 °C; SO2 and O2; log [H2O] = -5

Ni3S2 NiO

log [S ] T = 600 °C; SO and O ; log [H O] = 0

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0

-2

-4

-6

-8

-20 -10 0 log [O2]

NiS NiSO4

Ni3S2 NiO

Ni

log [Stot] T = 600 C; SO2 and O2; log [H2O] = 0