FIGURE 1.
FIGURE 2.
FIGURE 3.
FIGURE 4.
FIGURE 5.
FIGURE 6.
FIGURE 7.
FIGURE 8.
FIGURE 9.
FIGURE 10.
FIGURE 11.
Dyes chemical properties
| Pollutant | MWt [g⸱mol] | λmax [nm] | Chemical structure |
|---|---|---|---|
| Reactive yellow 17 | 452.79 | 530 | |
| Direct blue 53 | 1,418.94 | 545 |
Elemental composition of the industrial sludge samples
| Parameter | Unit | Value |
|---|---|---|
| Si concentration | mg⸱kg−1 | 13,600 |
| Zn concentration | mg⸱kg−1 | 2,300 |
| Cu concentration | mg⸱kg−1 | 1,100 |
| Mn concentration | mg⸱kg−1 | 9,200 |
| Fe concentration | mg⸱kg−1 | 7,850 |
| Hg concentration | mg⸱kg−1 | n.d. |
| Ni concentration | mg⸱kg−1 | 720 |
| Cd, Cr concentration | mg⸱kg−1 | b.d. |
| Pb concentration | mg⸱kg−1 | 680 |
| Moisture | % | 70 |
| pH | – | 6.6 |
Summary of coagulant dosage and removal efficiency results
| Coagulant | Dose of coagulants [mg⸱l−1] | RY17 pollutant | Removal efficiency [%] | DB53 pollutant | Removal efficiency [%] | ||
|---|---|---|---|---|---|---|---|
| initial turbidity [NTU] | final turbidity [NTU] | initial turbidity [NTU] | final turbidity [NTU] | ||||
| Recovered | 30 | 24.93 | 2.41 | 90.33 | 26.82 | 3.71 | 86.11 |
| Alum | 30 | 24.93 | 3.63 | 85.42 | 26.82 | 5.27 | 80.34 |