Table 3 Reaction stoichiometries and stability constants used in DLM calculations for kaolinite.
From: Surface complexation modeling of Cu(II) adsorption on mixtures of hydrous ferric oxide and kaolinite
Reaction | Log Stability Constant | V(Y) (Vmin(Y), Vmax(Y)) |
|---|---|---|
>KaoliniteOH + H+(aq) = >KaoliniteOH2+ | 2.1[38] | Â |
>KaoliniteOH = >KaoliniteO- + H+(aq) | -8.1[38] | Â |
Monodentate variable charge site: | Â | 23.3 |
>KaoliniteOH + Cu+2(aq) = >KaoliniteOCu+ + H+(aq) | -1.7 (this study) | (20.2, 27.1) |
Bidentate variable charge site: | Â | 28.5 |
2 > KaoliniteOH + Cu+2(aq) = >KaoliniteO2Cu + 2H+(aq) | -4.6 (this study) | (24.8, 33.2) |
Monodentate variable charge + ion exchange site (all log K's fit in this study): | Â | Â |
>KaoliniteOH + Cu+2(aq) = >KaoliniteOCu+ + H+(aq) | -1.9 (this study) | Â |
X(Na) + H+(aq) = X(H) + Na+(aq) | 4.1 (this study) | 44.9 |
2X(Na) + Cu+2(aq) = X2(Cu) + 2Na+(aq) | 0.72 (this study) | (38.9, 52.2) |
Monodentate variable charge + ion exchange site model (fixed Na-H exchange stability constant): | Â | Â |
>KaoliniteOH + Cu+2(aq) = >KaoliniteOCu+ + H+(aq) | -2.3 (this study) | Â |
X(Na) + H+(aq) = X(H) + Na+(aq) | 4.3 (this study) | 108 |
2X(Na) + Cu+2(aq) = X2(Cu) + 2Na+(aq) | 2.5[7] | (93.6, 126) |
Bidentate variable charge + ion exchange site model (fixed Na-H exchange stability constant): | -5.3 (this study) | Â |
2>KaoliniteOH + Cu+2(aq) = >KaoliniteO2Cu + 2H+(aq) | 4.6 (this study) | 62.6 |
X(Na) + H+(aq) = X(H) + Na+(aq) | 2.5[7] | (54.4, 72.9) |
2X(Na) + Cu+2(aq) = X2(Cu) + 2Na+(aq) | Â | Â |
Monodentate variable charge + ion exchange site model, no Cu sorption on ion exchange site (fixed Na-H exchange stability constant): | -1.8 (this study) 2.5[7] | 190 (165, 221) |
>KaoliniteOH + Cu+2(aq) = >KaoliniteOCu+ + H+(aq) | Â | Â |
X(Na) + H+(aq) = X(H) + Na+(aq) | Â | Â |
Bidentate variable charge + ion exchange site model, no Cu sorption on ion exchange site (fixed Na-H exchange stability constant): | -4.6 (this study) 2.5[7] | 33.8 (29.4, 39.3) |
2 > KaoliniteOH + Cu+2(aq) = >KaoliniteO2Cu + 2H+(aq) | Â | Â |
X(Na) + H+(aq) = X(H) + Na+(aq) | Â | Â |