Table 2

Conditions and results of reduction experiments conducted in this study. All concentrations are in μmol.kg-1. Values and their errors bigger than 10 are rounded to the nearest whole number, those smaller than 10 are rounded to the nearest tenth.
Metal/Alloy
 Run
 Solution
 T°C
 pHpre
 pHpost
 NH4+
 %
 NH4+norm*
 NO2-**
 NO3-**
Fe
 1
 Ar
 200
 5.7
 9.9
 171 ± 1
 -
 340 ± 21
 n.a.
 n.a.
Fe
 2
 650 N2
 200
 5.8
 8.9
 187 ± 1
 2.5
 371 ± 23
 n.a.
 n.a.
Fe
 3
 39/617 H2/N2
 200
 5.8
 8.4
 230 ± 1
 10
 455 ± 28
 n.a.
 n.a.
Fe
 4
 459 KCl in N2
 200
 6.2
 8.9
 267 ± 2
 15
 529 ± 32
 n.a.
 n.a.
Fe
 5
 484 KNO2 in N2
 200
 6.0
 9.8
 768 ± 1
 100
 1522 ± 93
 0
 0
Fe
 6
 465 KNO3 in N2
 200
 6.2
 9.8
 760 ± 8
 100
 1507 ± 92
 0
 0
Fe
 7
 485 KNO2 in Ar
 200
 6.0
 10.2
 749
 100
 1486 ± 91
 0
 0
Fe
 8
 477 KNO3 in Ar
 200
 6.2
 10.3
 752 ± 3
 100
 1491 ± 91
 0
 0
Ni
 9
 Ar
 200
 5.8
 8.7
 18
 -
 27 ± 3
 n.a.
 n.a.
Ni
 10
 650 N2
 200
 5.7
 8.3
 28
 1.5
 43 ± 5
 n.a.
 n.a.
Ni
 11
 39/617 H2/N2
 200
 5.8
 6.3
 30
 1.8
 45 ± 5
 n.a.
 n.a.
Ni
 12
 459 KCl in N2
 200
 6.2
 6.7
 20
 0.3
 30 ± 4
 n.a.
 n.a.
Ni
 13
 484 KNO2 in N2
 200
 6.0
 9.1
 559 ± 8
 100
 855 ± 102
 0
 0
Ni
 14
 465 KNO3 in N2
 200
 6.2
 9.0
 538 ± 7
 100
 823 ± 98
 0
 0
Ni
 15
 485 KNO2 in Ar
 200
 6.0
 9.3
 544 ± 7
 100
 833 ± 99
 0
 0
Ni
 16
 477 KNO3 in Ar
 200
 6.2
 9.3
 543 ± 4
 100
 830 ± 99
 0
 0
Ni50Fe50
 17
 Ar
 200
 5.8
 8.7
 15
 -
 40 ± 1
 n.a.
 n.a.
Ni50Fe50
 18
 650 N2
 200
 5.7
 7.9
 17
 0.3
 47 ± 1
 n.a.
 n.a.
Ni50Fe50
 19
 39/617 H2/N2
 200
 5.6
 8
 17
 0.3
 45 ± 1
 n.a.
 n.a.
Ni50Fe50
 20
 476 KCl in N2
 200
 6.3
 7.1
 14
 0
 39 ± 1
 n.a.
 n.a.
Ni50Fe50
 21
 480 KNO2 in N2
 200
 5.9
 9.8
 418 ± 3
 100
 1133 ± 29
 0
 0
Ni50Fe50
 22
 463 KNO3 in N2
 200
 6.0
 9.7
 490 ± 2
 100
 1330 ± 34
 0
 0
Ni50Fe50
 23
 474 KNO2 in Ar
 200
 6.1
 10.3
 475 ± 5
 100
 1289 ± 33
 0
 0
Ni50Fe50
 24
 487 KNO3 in Ar
 200
 6.0
 9.9
 476 ± 6
 100
 1293 ± 33
 0
 0
Ni81Fe19
 25
 Ar
 200
 5.8
 8.6
 18
 -
 98 ± 7
 n.a.
 n.a.
Ni81Fe19
 26
 650 N2
 200
 5.7
 7.9
 19
 0.2
 99 ± 7
 n.a.
 n.a.
Ni81Fe19
 27
 39/617 H2/N2
 200
 5.6
 8.3
 19
 0.2
 103 ± 7
 n.a.
 n.a.
Ni81Fe19
 28
 476 KCl in N2
 200
 6.3
 6.2
 18 ± 1
 0
 96 ± 7
 n.a.
 n.a.
Ni81Fe19
 29
 480 KNO2 in N2
 200
 5.9
 9.9
 410 ± 6
 100
 2186 ± 153
 0
 0
Ni81Fe19
 30
 463 KNO3 in N2
 200
 6.0
 9.8
 483 ± 4
 100
 2576 ± 180
 0
 0
Ni81Fe19
 31
 474 KNO2 in Ar
 200
 6.1
 10.3
 485 ± 4
 100
 2583 ± 180
 0
 0
Ni81Fe19
 32
 487 KNO3 in Ar
 200
 6.0
 9.9
 493 ± 3
 100
 2626 ± 183
 0
 0
-
 33
 497 KNO2
 200
 6.0
 9.4
 45
 9.1
 -
 288 ± 2
 73 ± 1
-
 34
 444 KNO3
 200
 6.1
 6.4
 3.6
 0.8
 -
 273 ± 1
 129 ± 1
-
 35
 506 FeCl2 in N2
 200
 4.7
 3.3
 8.1 ± 0.1
 1.2
 -
 n.a.
 n.a.
-
 36
 492 NiCl2 in N2
 200
 5.3
 5.7
 8.0 ± 0.3
 1.2
 -
 n.a.
 n.a.
Fe
 37
 Ar
 70
 5.7
 7.6
 3.8
 -
 7.4 ± 0.5
 n.a.
 n.a.
Fe
 38
 650 N2
 70
 5.8
 8.5
 3.6
 0
 7.2 ± 0.4
 n.a.
 n.a.
Fe
 39
 492 KNO2 in O2
 70
 6.9
 10.1
 559 ± 3
 100
 1107 ± 68
 0
 0
Fe
 40
 502 KNO2 in N2
 70
 6.1
 9.8
 550 ± 3
 100
 1091 ± 67
 0
 0
Fe
 41
 511 KNO3 in O2
 70
 6.7
 9.9
 558 ± 2
 98
 1106 ± 68
 0
 8.8 ± 0.2
Fe
 42
 486 KNO3 in N2
 70
 6.3
 10.1
 512 ± 6
 98
 1015 ± 62
 0
 9.6 ± 0.2
Ni
 43
 Ar
 70
 5.7
 7.6
 0.9
 -
 1.4 ± 0.2
 n.a.
 n.a.
Ni
 44
 650 N2
 70
 5.8
 6.9
 0.9
 0
 1.4 ± 0.2
 n.a.
 n.a.
Ni
 45
 492 KNO2 in O2
 70
 6.9
 10.1
 528 ± 2
 100
 807 ± 96
 0
 0
Ni
 46
 502 KNO2 in N2
 70
 6.1
 9.9
 534 ± 3
 100
 818 ± 97
 0
 0
Ni
 47
 511 KNO3 in O2
 70
 6.7
 10.2
 521 ± 5
 100
 797 ± 95
 0
 0
Ni
 48
 486 KNO3 in N2
 70
 6.3
 10.2
 534 ± 5
 100
 817 ± 97
 0
 0
Ni50Fe50
 49
 Ar
 70
 5.7
 8.2
 0.4
 -
 1.2
 n.a.
 n.a.
Ni50Fe50
 50
 650 N2
 70
 5.8
 8.3
 0.4
 0
 1.2
 n.a.
 n.a.
Ni50Fe50
 50
 492 KNO2 in O2
 70
 6.9
 8.4
 22 ± 1
 3.9
 61 ± 2
 473 ± 3
 0
Ni50Fe50
 51
 502 KNO2 in N2
 70
 6.1
 8.1
 23 ± 1
 2.8
 62 ± 2
 488 ± 2
 0
Ni50Fe50
 52
 511 KNO3 in O2
 70
 6.7
 8.0
 19 ± 1
 8
 53 ± 1
 0
 470 ± 2
Ni50Fe50
 53
 486 KNO3 in N2
 70
 6.3
 8.4
 28 ± 1
 6.2
 77 ± 2
 0
 456 ± 2
Ni81Fe19
 54
 Ar
 70
 5.7
 8.2
 0.5
 -
 2.9 ± 0.2
 n.a.
 n.a.
Ni81Fe19
 55
 650 N2
 70
 5.8
 8.1
 0.5
 0
 2.7 ± 0.2
 n.a.
 n.a.
Ni81Fe19
 56
 492 KNO2 in O2
 70
 6.9
 9.2
 23 ± 1
 4.7
 125 ± 9
 410 ± 1
 0
Ni81Fe19
 57
 502 KNO2 in N2
 70
 6.1
 9.2
 71 ± 2
 14
 379.27
 406 ± 1
 0
Ni81Fe19
 58
 511 KNO3 in O2
 70
 6.7
 8.6
 35
 6.8
 186 ± 13
 13 ± 1
 425 ± 2
Ni81Fe19
 59
 486 KNO3 in N2
 70
 6.3
 8.7
 69 ± 2
 14.2
 370 ± 26
 9.1 ± 0.7
 424 ± 3
Fe
 60
 Ar
 22
 5.7
 6.4
 0.7
 -
 1.4
 n.a.
 n.a.
Fe
 61
 650 N2
 22
 5.8
 6.6
 0.7
 0
 1.4
 n.a.
 n.a.
Fe
 62
 541KNO2 in O2
 22
 6.2
 10.8
 544 ± 6
 100
 1078 ± 66
 0
 0
Fe
 63
 549 KNO2 in N2
 22
 6.0
 10.6
 542 ± 5
 99
 1075 ± 66
 0
 0
Fe
 64
 529 KNO3 in O2
 22
 6.4
 10.5
 527 ± 4
 100
 1044 ± 64
 0
 0
Fe
 65
 521 KNO3 in N2
 22
 5.9
 10.8
 486 ± 5
 93
 963 ± 59
 0
 0
Ni
 66
 Ar
 22
 5.7
 6.9
 0.4
 -
 0.6
 n.a.
 n.a.
Ni
 67
 650 N2
 22
 5.8
 5.6
 0.4
 0
 0.6
 n.a.
 n.a.
Ni
 68
 541KNO2 in O2
 22
 6.2
 10.6
 422 ± 3
 78
 646 ± 77
 0
 0
Ni
 69
 549 KNO2 in N2
 22
 6.0
 10.7
 451 ± 5
 82
 690 ± 82
 0
 0
Ni
 70
 529 KNO3 in O2
 22
 6.4
 10.2
 139
 26
 213 ± 25
 43
 36
Ni
 71
 521 KNO3 in N2
 22
 5.9
 10.1
 364 ± 1
 70
 557 ± 66
 1.2
 22
Ni50Fe50
 72
 Ar
 22
 5.7
 6.3
 0
 -
 0
 n.a.
 n.a.
Ni50Fe50
 73
 650 N2
 22
 5.8
 6.3
 0
 0
 0
 n.a.
 n.a.
Ni50Fe50
 74
 541 KNO2 in O2
 22
 6.2
 6.8
 1.4
 0.3
 3.9 ± 0.1
 553 ± 2
 0
Ni50Fe50
 75
 549 KNO2 in N2
 22
 6.0
 7.7
 1.1 ± 0.1
 0.2
 3.1 ± 0.1
 556
 0
Ni50Fe50
 76
 529 KNO3 in O2
 22
 6.4
 7.2
 0.8
 0.2
 2.1 ± 0.1
 0
 526 ± 1
Ni50Fe50
 77
 521 KNO3 in N2
 22
 5.9
 7.3
 1
 0.2
 2.7 ± 0.1
 0
 523 ± 2
Ni81Fe19
 78
 Ar
 22
 5.7
 6.9
 0
 -
 0
 n.a.
 n.a.
Ni81Fe19
 79
 650 N2
 22
 5.8
 6.6
 0
 0
 0
 n.a.
 n.a.
Ni81Fe19
 80
 541 KNO2 in O2
 22
 6.2
 9.4
 3 ± 0.1
 0.6
 16 ± 1
 515 ± 2
 0
Ni81Fe19
 81
 549 KNO2 in N2
 22
 6.0
 9.3
 1.9 ± 0.1
 0.4
 10 ± 1
 539 ± 3
 0
Ni81Fe19
 82
 529 KNO3 in O2
 22
 6.4
 8.9
 0
 0
 0
 0
 493 ± 1
Ni81Fe19
 83
 521 KNO3 in N2
 22
 5.9
 9.0
 1.9 ± 0.1
 0.4
 10 ± 1
 0
 482

"n.a." denotes "not analyzed, "-" not applicable. * denotes NH4+ concentration formed in the experiment normalized to 1 m2 of surface area of the metal/alloy. ** denote residual concentration after the experiment was completed.

Smirnov et al. Geochemical Transactions 2008 9:5   doi:10.1186/1467-4866-9-5