Kinetics constants for MB and RhB adsorption at 150, 175, and 200 mg L−1 dye concentrations (pH = 6, T = 25 °C, and adsorbent: 30 mg).
| Dye | q e, exp (mg g−1) | Pseudo-first-order kinetic | Pseudo-second-order kinetic | Intraparticle diffusion | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| k 1 (min−1) | q e, cal (mg g−1) | R 1 2 | k 2 (g mg−1 min−1) | q e, cal (mg g−1) | R 2 2 | k p | I | R 3 2 | ||
| MB | ||||||||||
| 150 | 147.6 | 0.07 | 5 | 0.967 | 0.009 | 149.3 | 1 | 6.7 | 82.4 | 0.4349 |
| 175 | 169.3 | 0.05 | 13 | 0.995 | 0.005 | 172.4 | 0.9999 | 8.08 | 91.07 | 0.4748 |
| 200 | 191.2 | 0.04 | 17 | 0.982 | 0.003 | 196.1 | 0.9999 | 9.4 | 98.8 | 0.5091 |
| RhB | ||||||||||
| 100 | 96 | 0.05 | 4.5 | 0.945 | 0.003 | 102.1 | 0.999 | 6.5 | 38.7 | 0.6653 |
| 125 | 111 | 0.04 | 10 | 0.989 | 0.001 | 123.5 | 0.9957 | 8.4 | 36.6 | 0.792 |
| 150 | 124 | 0.03 | 15 | 0.989 | 0.001 | 135.1 | 0.9957 | 9.3 | 44.9 | 0.7529 |