Table 1: Dissolution reactions for Mg and Ni end-members of garnierite and Fayalite-Fe, with the corresponding equilibrium constants at 25 °C and 1 bar used for the PHREEQC modelling.
|
Minerals |
Reaction |
Log K |
|
Nepouite |
Ni3Si2O5(OH)4 + 6.00 H+ = 3.00 Ni++ + 2.00 SiO2 + 5.00 H2O |
21.5a |
|
Pimelite |
Ni3Si4O10(OH)2:H2O + 6.000 H+ = 3.00 Ni++ + 4.00 SiO2 + 5.00 H2O |
11.46a |
|
Falcondoite |
Ni4Si6O15(OH)2:6H2O + 8.0000 H+ = + 4.0000 Ni++ + 6.0000 SiO2 + 11.0000 H2O |
12.31a |
|
Kerolite |
Mg3Si4O10(OH)2:H2O + 6.000 H+ = 3.00 Mg++ + 4.00 SiO2 + 5.00 H2O |
25.55a |
|
Ferrosilite |
FeSiO3 + 2.0000 H+ = + 1.0000 Fe++ + 1.0000 H2O + 1.0000 SiO2 |
7.447 b |
|
Enstatite |
MgSiO3 + 2.0000 H+ = + 1.0000 H2O + 1.0000 Mg++ + 1.0000 SiO2 |
11.3269b |
|
Fosterite |
Mg2SiO4 + 4.0000 H+ = + 1.0000 SiO2 + 2.0000 H2O + 2.0000 Mg++ |
27.8626llb |
|
Fayalite |
Fe2SiO4 + 4.0000 H+ = + 1.0000 SiO2 + 2.0000 Fe++ + 2.0000 H2O |
19.1113b |
|
Fe(OH)2Ni |
>Fe(OH)2-1 + Ni2+ = Fe(OH)2Ni+ |
12.60c |
|
(FeOH)2Ni |
2 > FeOH-0.5 + Ni2+ = (> FeOH)2Ni+ |
10.1c |
|
Fe(OH)2Co |
> Fe(OH)2-1 + Co2+ = Fe(OH)2Co+ |
12.80d |
|
(FeOH)2Co |
2 > FeOH-0.5 + Co2+ = (> FeOH)2Co+ |
10.60d |