Research Article
Chemical Modifications of Cassava Peel as Adsorbent Material for Metals Ions from Wastewater
Table 9
Thermodynamic parameters for modified adsorbents from cassava peels in the removal of Cd(II), Pb(II), and Cr(III).
| Adsorbents | Temp. °C | Cd(II) | Pb(II) | Cr(III) | | | | | | | | | | | | | | | |
| M. H2O2 | 15 | 6.4 | 3.0 | 15.5 | 43.6 | 0.93 | 11.8 | −3.6 | −59.5 | −194.2 | 0.92 | 10.9 | −1.4 | −5.7 | −15.1 | 0.93 | 25 | 6.1 | 2.6 | 10.7 | −1.7 | 10.5 | −1.2 | 35 | 7.8 | 2.1 | 10.0 | 0.3 | 10.7 | −1.1 | 45 | 8.7 | 1.7 | 10.5 | 2.2 | 10.5 | −0.9 | 55 | 9.0 | 1.3 | 10.7 | 4.1 | 10.1 | −0.8 |
| M. H2SO4 | 15 | 5.6 | 3.8 | 5.6 | 6.5 | 0.98 | 10.9 | −1.0 | −59.6 | −203.9 | 0.80 | 10.1 | −0.2 | −9.9 | −34.0 | 0.98 | 25 | 6.0 | 3.7 | 7.7 | 1.1 | 8.6 | 0.2 | 35 | 6.3 | 3.7 | 7.5 | 3.1 | 9.2 | 0.5 | 45 | 6.2 | 3.6 | 8.6 | 5.2 | 9.6 | 0.8 | 55 | 6.9 | 3.5 | 8.4 | 7.2 | 8.8 | 1.2 |
| M. NaOH | 15 | 12.5 | −5.2 | −29.7 | −85.2 | 0.87 | 11.8 | 21.5 | −0.26 | −75.5 | 0.89 | 11.6 | −3.2 | 18.1 | 74.1 | 0.87 | 25 | 11.6 | −4.3 | 11.7 | 22.2 | 11.7 | −4.0 | 35 | 11.5 | −3.5 | 11.6 | 23.0 | 11.7 | −4.7 | 45 | 11.9 | −2.6 | 11.5 | 23.8 | 11.9 | −5.4 | 55 | 11.2 | −1.8 | 11.7 | 24.5 | 12.0 | −6.2 |
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(mg g−1); (KJ mol−1); (KJ mol−1); (J mol−1 K−1).
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