Table 1.
Parameters of Langmuir and Freundlich models for targeted olive-leaf polyphenolic compounds adsorbed by grapevine-pruning-residues biochar.
| Parameters | VA-4-g | Hyty | L-7-g | L-7-r | A-7-g | Olp | Sum | |
|---|---|---|---|---|---|---|---|---|
| Langmuir isotherm | qmax (mg/g) | 1.54 | 3.08 | 1.21 | 2.44 | 0.47 | 0.05 | 6.83 |
| KL (L/mg) | −0.28 | 0.38 | 102 | −10.1 | −4.17 | −41.20 | 9.64 | |
| RL | (−2.62)–(−0.01) | 0.05–0.35 | 0.00–0.91 | (−105)–(−0.02) | (−0.66)–(−0.05) | 0.00–1.32 | 0.02–0.50 | |
| R2 | 0.999 | 0.999 | 0.549 | 0.990 | 0.918 | 0.980 | 0.945 | |
| Freundlich isotherm | Kf (mg/g) × (L/g)n |
0.32 | 1.20 | 1.44 | 0.40 | 1.35 | 20.4 | 9.49 |
| 1/n | 0.93 | 0.80 | 0.78 | 0.89 | 0.48 | 0.21 | 0.47 | |
| R2 | 0.999 | 0.855 | 0.854 | 0.966 | 0.872 | 0.972 | 0.978 |
VA-4-g—Vanillic acid-4-glucoside; Hyty—Hydroxytyrosol; L-7-g—Luteolin-7-O-glucoside; L-7-r—Luteolin-7-O-rutinoside; A-7-g—Apigenin-7-O-glucoside; Olp—Oleuropein; Sum—Sum of polyphenols.