Table 2

Induction time and total reaction times, and final solid products of the hydrothermal transformation of mackinawite to pyrite a).

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.

Hunger and Benning Geochemical Transactions 2007 8:1   doi:10.1186/1467-4866-8-1