Comparison of indigo carmine adsorption capacity using APAN/Fe3O4–MPA composites nanofibers with other reported adsorbents.
| Material | pH | Dye concentrations (mg L−1) | Adsorption capacity (mg g−1) | Equilibrium time (min) | Reference |
|---|---|---|---|---|---|
| Charcoal from extracted residue of coffee beans | — | 10 | 30 | 1200 | 11 |
| Charcoal from rice bran | 7 | 10 | 9.7 | 180 | 10 |
| Chitin | — | 10 | 5.8 | — | 38 |
| Chitosan | — | 90 | 71.8 | 120 | 38 |
| Activated sewage sludge | — | 100 | 60 | 190 | 40 |
| Glutaraldehyde cross-linked chitosan | 4 | 30 | 1.8 | 200 | 55 |
| N-Vinyl-2-pyrrolidone/acrylonitrile hydrogels | — | 50 | 2.3 | 7200 | 56 |
| Calcium hydroxide | 12 | 0.05 | 0.95 | 50 | 6 |
| Mg/Fe layered double hydroxide nanoparticles | 9.5 | 14 | 55.5 | 30 | 57 |
| Activated carbon | 2 | 20 | 87.8 | 120 | 58 |
| Montmorillonite | 3 | 20 | 40 | 120 | 59 |
| PAN/Fe3O4–MPA composites nanofibers | 5 | 20 | 154.5 | 25 | This work |