Table 2. Comparison of the Maximum Adsorption Capacity of Zn(II), Pb(II), Cd(II), and Hg(II) on Various Adsorbents.
| adsorbent | metal ions | qmax (mmol/g) | refs |
|---|---|---|---|
| soy protein | Zn(II) | 3.90 | (9) |
| Cd(II) | 1.07 | ||
| Pb(II) | 1.13 | ||
| carboxyl-modified lignocelluloses – jute fiber | Pb(II) | 0.76 | (52) |
| Cd(II) | 0.79 | ||
| chitosan polyitaconic acid | Cd(II) | 3.60 | (53) |
| Pb(II) | 1.61 | ||
| porous starch-functionalized carbon disulfide | Pb(II) | 0.52 | (54) |
| calcium alginate | Pb(II) | 0.80 | (55) |
| Cd(II) | 0.02 | ||
| Klebsiellasp. 3S1 | Zn(II) | 0.74 | (56) |
| durian peel | Zn(II) | 0.56 | (57) |
| rapeseed waste | Zn(II) | 0.21 | (58) |
| succinylated starch | Zn(II) | 0.20 | (59) |
| Cd(II) | 0.11 | ||
| dibenzo-18-crown-grafted corn starch | Zn(II) | 5.77 | (60) |
| Cd(II) | 3.27 | ||
| amino-functionalized magnetic graphene | Pb(II) | 0.13 | (61) |
| chitosan-coated diatomaceous earth | Zn(II) | 1.95 | (62) |
| cross-linked starch phosphate carbamate cross-linked starch phosphate | Pb(II) | 2.01 | (63) |
| Zn(II) | 2.00 | (64) | |
| ammonium thioglycolate functionalized egg shell membrane | Hg(II) | 0.69 | (65) |
| silica-gel-supported sulfur-capped PAMAM dendrimers | Hg(II) | 1.89 | (66) |
| layered double hydroxide intercalated with the MoS42– ion | Hg(II) | 2.49 | (15) |
| Pb(II) | 1.40 | ||
| thiol-functionalized mesoporous silica-coated magnetite nanoparticles | Hg(II) | 0.05 | (67) |
| magnetite@carbon/dithizone nanocomposite | Hg(II) | 0.14 | (68) |
| chitosan–iron(III) biocomposite beads | Hg(II) | 1.8 | (29) |
| Pb(II) | 0.56 | ||
| potato starch phosphate (PSP) | Zn(II) | 2.00 | this study |
| Pb(II) | 0.51 | this study | |
| Cd(II) | 0.81 | this study | |
| Hg(II) | 0.26 | this study | |
| native starcha | Zn(II) | 0.68 | |
| Pb(II) | 0.13 | ||
| Cd(II) | 0.17 | ||
| Hg(II) | 0.07 |
a
Batch experiments were carried out under similar conditions for the purpose of comparison.