Table 2
Surface complexation reactions relevant for the present system at 25°C and I = 0, used in PHREEQC. Data for reactions 01 to 06 from (Pokrovsky et al., 2000); log K for reactions 07, 08 and 09 are determined from experimental results and presented in Table 5
| Reactions | Surface complexation equilibrium reactions | log K°int (25°C, I = 0) | |
|---|---|---|---|
| Data from literature and thermodynamic databases | 01 | CaOH° – H+ = > > CaO− | −12 |
| 02 | CaOH° + H+ = > CaOH2+ | 11.5 | |
| 03 | CaOH° + CO32− + 2H+ = > CaHCO3° + H2O | 23.5 | |
| 04 | CaOH° + CO32− + H+ = > CaCO3− + H2O | 17.1 | |
| 05 | CO3H° = > CO3− + H+ | −5.1 | |
| 06 | CO3H° + Ca2+ = > CO3Ca+ + H+ | −1.7 | |
| Fit from experimental data | 07 | CO3Ca+ + Zn2+ = > CO3Zn+ + Ca2+ | |
| 08 | CO3Ca+ + Sr2+ = > CO3Sr+ + Ca2+ | ||
| 09 | CO3Ca+ + Mn2+ = > CO3Mn+ + Ca2+ |