Table 2.
Temperature | Induction Times (min) b) | Reaction Time (min) | Products (ED-XRD) | ||
t-0 mack | t+0 grei | t+0 pyr | |||
200°C c) | 0 | 8 | 0 | 90 | Pyrite |
200°C c) | 0 | 4 | 0 | 70 | Pyrite, Greigite |
175°C | 7 | n.a.d) | 6 | 60 | Pyrite, Greigite |
150°C | 4 | 6 | 12 | 74 | Pyrite, Greigite |
125°C | 25 (± 3) | n.a. | 22 | 110 | Pyrite |
100°C | 77 (± 19) | n.a. | 117 (± 30) | 311 e) | Mackinawite, Pyrite |
a) All experiments: 1.25 ± 0.13 mmol FeS and 1.25 ± 0.13 mmol zerovalent S as polysulfide.
b) Mean errors in induction times, unless stated otherwise: ± 1. t-0 mack: induction time for mackinawite decay; t+0 grei, t+0 pyr: induction time for greigite and pyrite growth, respectively.
c) The reaction at 200°C was conducted in duplicate.
d) n.a.: not available.
e) Reaction was interrupted before completion.