| Mineral: |
Kaolinite |
| Reference: |
AFI02 |
| SCM Type: |
ECC - Extended Constant Capacitance
(C1: 3.0 F/m2, C2: 7.0 F/m2) |
| Ionic Strength: |
0.005 mol/L of
KNO3
|
| Site Type: |
»X-OH |
| PZC: |
|
| pK1: |
3.24 |
pK1°I=0 (Conversion to I = 0): |
3.21 |
pK12.31 nm−2 (normalized): |
3.16 |
| pK2: |
7.15 |
pK2°I=0 (Conversion to I = 0): |
7.12 |
pK22.31 nm−2 (normalized): |
7.23 |
| Site Density in nm-2: |
1.9271 |
| Original Site Density: |
3.2 µmol / m² surface
|
| Solid/Liquid Ratio in g/L: |
0.0 |
| pH Range: |
|
| Temperature in K: |
|
| Method for Site Density: |
| Method for Protolysis: | Potentiometric Titration |
| Fit Method: |
| Comment: |
inner capacitance 3.0 F/m^2; outer capacitance 7.0 F/m^2; N2 atmosphere; 2 distinct populations of adsorption sites on the kaolinite surface: relatively sparse ion-exchange sites on the siloxane faces XH (significant adsorption between pH 3 and 5); =XH + K+ = =XK + H+ with pK=2,88 and SSD=2.3µmol/m^2; and more closely spaced variable-charge hydroxyl sites SOH (probably aluminol groups at crystal edges); pK from [AJW97] (CC model); N2 atmosphere |
| |
