Table 3. Adsorption Isotherm Parameters of Each Dye Adsorption on PPC by Langmuir, Freundlich, and Redlich–Peterson Models.
| isotherm model | corresponding value | MO | RhB | MB | CV |
|---|---|---|---|---|---|
| Langmuir | Qmax | 239.1 | 2821.8 | 580.5 | 396.6 |
| KL | 0.444 | 0.0522 | 1.03 | 0.592 | |
| adj. R2 | 0.945 | 0.999 | 0.996 | 0.975 | |
| separation factor | RL | 0.011–0.082 | 0.005–0.019 | 0.001–0.005 | 0.005–0.063 |
| Freundlich | KF | 102.3 | 899.8 | 316.5 | 154.4 |
| n | 4.84 | 5.93 | 9.28 | 5.00 | |
| adj. R2 | 0.948 | 0.777 | 0.617 | 0.752 | |
| Redlich–Peterson | KR | 147.8 | 147.3 | 596.5 | 234.7 |
| aR | 0.820 | 0.0522 | 1.03 | 0.592 | |
| β | 0.93 | 1 | 1 | 1 | |
| adj. R2 | 0.931 | 0.999 | 0.994 | 0.968 |