Comparison of adsorption capacity of PAA/DB18C6/GO hydrogel for Sr2+ with other adsorbents.
| Adsorbents | Initial Sr2+ concentration (mg L−1) | Contact time (h) | Initial pH | Maximum adsorption capacity (mg g−1) | Reference |
|---|---|---|---|---|---|
| Natural zeolite | 10 | 48 | 7.9 | 1.3 | 16 |
| Amorphous sodium titanates | 438.6 | 96 | 7 | 193.93 | 42 |
| ZrP/18C6 | 380 | 6 | 7 | 195.74 | 43 |
| Polyvinyl alcohol–sulfosuccinic acid | 200 | 6 | 6.0 | 60.7 | 44 |
| P(vinylsulphonic acid/2-acryloamido-2-methyl-1-propanesulphonic acid/magnetic nanoparticles)-carboxymethylcellulose | 400 | 24 | 6 | 330 | 45 |
| Poly(acrylonitrile–butadiene–styrene) | 400 | 1 | 7 | 177 | 46 |
| Hydroxyapatite/poly(acrylamide–acrylic acid) | 50 | 1 | 6 | 53.59 | 47 |
| Acrylic acid/charcoal/montmorillonite | 100 | 48 | 9.8 | 26.68 | 48 |
| Methacrylic acid cryogels | 100 | 24 | 6.0 | 209 | 25 |
| Poly(N-vinyl imidazole-cl-ethylene glycol dimethacrylate) | 1000 | 1 | 7.0 | 240.96 | 49 |
| PAA | 772 | 5 | 7 | 347.85 | This study |
| PAA/DB18C6/GO | 772 | 5 | 7 | 379.35 | This study |