| Short term mode (3-h contact time, pH = 1.5) | |||
| Kf ±0.02 | n ±0.02 | R2 | |
| Total Cr | 0.942 | 1.22 | 0.996 |
| Cr(VI) | 0.631 | 1.34 | 0.992 |
| Long term mode (5-day contact time, pH = 1.5) | |||
| Kf ±0.02 | n ±0.02 | R2 | |
| Total Cr | 0.307 | 0.940 | 0.981 |
| Cr(VI) | 2.988 | 1.360 | 1.000 |
| Short term mode (3-h contact time, pH = 2.0) | |||
| Kf ±0.02 | n ±0.02 | R2 | |
| Total Cr | 5.999 | 2.478 | 0.969 |
| Cr(VI) | 4.997 | 2.191 | 0.992 |
| Long term mode (5-day contact time, pH = 2.0) | |||
| Kf ±0.02 | n ±0.02 | R2 | |
| Total Cr | 0.178 | 0.609 | 0.985 |
| Cr(VI) | 0.172 | 0.755 | 0.985 |