Table 4.
Kinetic parameters of the W–M, D–W, and HSDM models for the adsorption of Cr(VI) and dyes onto MgAl-LDH@SiO2.
| Model | Parameter | Cr(VI) | AB-225 | AV-109 | AG-40 |
|---|---|---|---|---|---|
| W–M (Step 1) |
kp1 (mg g−1 min−0.5) | 9.726 ± 0.30 | 23.39 ± 0.94 | 21.07 ± 1.05 | 47.59 ± 1.88 |
| C (mg g−1) | 21.81 | 110.9 | 97.47 | 248.23 | |
| R 2 | 0.999 | 0.999 | 0.999 | 0.998 | |
| W–M (Step 2) |
kp2 (mg g−1 min−0.5) | 0.435 ± 0.01 | 0.264 ± 0.02 | 0.352 ± 0.02 | 0.527 ± 0.0 |
| C (mg g−1) | 79.08 | 237.1 | 214.3 | 467.9 | |
| R 2 | 0.998 | 0.998 | 0.998 | 0.998 | |
| D–W | K | 0.0215 ± 0.00 | 0.0319 ± 0.00 | 0.0312 ± 0.00 0.0217 |
0.0348 ± 0.00 |
| R 2 | 0.845 | 0.819 | 0.826 | 0.736 | |
| HSDM | Ds | 2.48 × 10−11 ± 0.00 | 3.52 × 10−11 ± 0.00 | 3.46 × 10−11 ± 0.00 | 3.72 × 10−11 ± 0.00 |
| R 2 | 0.835 | 0.816 | 0.824 | 0.731 |