Mineral: |
Hematite |
Reference: |
LH99 |
SCM Type: |
TL - Triple Layer |
Ligand: |
UO2<2+>
- uranyl(VI)
|
Site Type: |
»Fe(s)-OH |
Equation: |
2 »Fe(s)-OH + UO2<2+> + CO3<2-> ⇔ (»Fe(s)-O)2-UO2CO3<2-> + 2 H<1+> |
LogK: |
4.555 LogK°I=0 (Conversion to I = 0): 5.20
LogK2.31 nm−2 (SSD-normalized): 2.62
|
Experiment: |
Batch Sorption Experiments |
Ionic Strength: |
0.1 mol/L
NaClO4
|
Temperature: |
298.15 K |
Solid/Liquid Ratio: |
9.0 g/L |
pH Range: |
3-10 |
Ligand Concentration Range: |
1E-6 mol/L |
Fit Method: |
FITEQL |
Comment: |
log K determined for I =0; 25+-0.1°C; assumed to be same reaction for strong and weak sites; original reaction equation in the study: 2 »Fe(s)-OH + UO2<2+> + H2CO3 = (»Fe(s)-O)2-UO2CO3<2-> + 4 H<1+> with logK = -12.14, formation constants: logK1 = -6.366 for the reaction H2CO3 = H<1+> + HCO3<1->[FNK96], logK2 = -10.329 for HCO3<1-> = H<1+> + CO3<2-> [GFFGN03] --> so for H2CO3 = 2H<1+> + CO3<2-> the logK = -16.695 |
|