Table 5.
Comparison of Cr (VI) adsorption capacity with other adsorbents
| Adsorbent | Maximum capacity (mg/g) | Dose g/L | T° C | pH | Best fitting isotherm and kinetics | References |
|---|---|---|---|---|---|---|
| Coffee and tea residue |
87.72 94.34 |
2 | 30 | 2 | Freundlich and pseudo-second order | (Cherdchoo et al. 2019) |
| Tea residues | 79.08 | 6 | 30 | 3.9 | Langmuir and pseudo-second order | (Nigam et al. 2019) |
| Black cumin seeds | 9.98 | 1 | 40 | 1 | Langmuir and pseudo-second order | (Thabede et al. 2020) |
| Harpagophytum residues | 77.24 | 0.19 | 35 | 1 | Freundlich and pseudo-second order | (Shooto 2020b) |
| Hyacinth and Lemnaminor Leaves |
79.24 61.0 |
1 1 |
25 ± 1 25 ± 1 |
2 2 |
Langmuir and pseudo-second order; Langmuir and pseudo-second order | (Balasubramanian et al. 2020) |
| Mango bark | 78.96 | 0.12 | 30 | 2 | Langmuir and pseudo-second order | (Pathania et al. 2020) |
| Mentha piperita | 29.23 | 0.45 | 25 | 2 | Freundlich and pseudo-second order | (Al et al. 2020) |
| Acacia sawdust | 6.34 | 4.9 | 30 | 2 | Langmuir and pseudo-second order | (Khalil et al. 2020) |
| Rice husk | 379.63 | 0.6 | 20 ± 2 | 5.2 | Langmuir and pseudo-second order | (Khalil et al. 2021) |
| Hyacinth root | 1.28 | 14 | 25 ± 5 | 3 | Freundlich and pseudo second order | (Kumar & Chauhan 2019) |
| Acorus calamus | 14.64 | 0.2 | 25 | 1 | Langmuir and pseudo-second order | (Shooto 2020a) |
| Sambucus nigra L | 6.39 | 3 | 18 | 2 | Non-linear Freundlich, pseudo-second order, and intra-particle diffusion | Present study |