| Titre : | Adsorption of chromium(VI) from aqueous solutions using an imidazole functionalized adsorbent (2008) |
| Auteurs : | Hyung-Jun Park, Auteur ; Lawrence L. Tavlarides, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Industrial & engineering chemistry research (Vol. 47 N°10, Mai 2008) |
| Article en page(s) : | p. 3401–3409 |
| Note générale : | Bibliogr. p. 3408-3409 |
| Langues : | Anglais |
| Tags : | Chromium(VI) -- separation ; Imidazole functionalized adsorbent ; Sol-gel synthesis method |
| Résumé : | Separation of chromium(VI) from aqueous solutions is investigated using an imidazole functionalized sol−gel adsorbent. This adsorbent has been formed by the sol−gel synthesis method. The speciation diagram of Cr(VI) in an aqueous system with varying pH is studied by analyses of the equilibria equations. Batch adsorption equilibrium studies show a decrease in chromium uptake capacity with increase in pH in the range from 2 to 9, and the uptake capacity at pH 2.5 is found to be 2.93 mmol/g (152 mg/g). The Langmuir adsorption isotherm gives a satisfactory fit of the adsorption data. A kinetics study conducted with different concentrations of chromium(VI) in a batch reactor shows a rapid rate of adsorption. The adsorbent shows a high selectivity toward Cr(VI) and negligible adsorption of Cu(II), Ni(II), and Zn(II). Adsorption tests in a fixed bed column show a sharp breakthrough curve. Stripping of the chromium-loaded column bed is achieved using 4 M HNO3. Twenty cycles of adsorption and desorption process are performed for SOL-IPS adsorbent. The adsorbent maintains 90% of original capacity during 15 cycles, and loss of 25% of capacity until 20 cycles of operation. The imidazole functional adsorbent is demonstrated to be an effective sorbent material for the separation of chromium(VI) from aqueous solutions. |
| En ligne : | http://pubs.acs.org/doi/abs/10.1021/ie7017096 |
