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Alumina nanoparticles for the removal of Ni(II) from aqueous solutions / Y. C. sharma in Industrial & engineering chemistry research, Vol. 47 n°21 (Novembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°21 (Novembre 2008) . - p 8095–8100 Titre : Alumina nanoparticles for the removal of Ni(II) from aqueous solutions Type de document : texte imprimé Auteurs : Y. C. sharma, Auteur ; V. Srivastava, Auteur ; Upadhyay, S., Auteur Année de publication : 2008 Article en page(s) : p 8095–8100 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Alumina  Nanoparticles Résumé : Alumina nanoparticles were developed by the sol−gel method and were used for the removal of Ni(II) ions from aqueous solutions. The nanoparticles were characterized by TEM and XRD. Nanoparticles of alumina were then used for removal of Ni(II) ions from aqueous solutions of nickel. The nanosize of the adsorbent was confirmed by TEM and XRD. Removal (%) was found to be dependent on the initial concentration of nickel, and maximum removal was found to be 96.6% at 25 mg/L Ni(II). The removal increased from 99 to 99.6% by decreasing the initial concentration from 75 to 25 mg/L. Equilibrium time was found to be 120 min. As expected, higher removal was obtained at higher adsorbent dose. The removal was governed by first-order kinetics, and the value of the rate constant of adsorption was found to be 1.83 × 10−2 min−1 at 25 mg/L and 25 °C. The removal was found to be pH dependent, and maximum removal was found to be at pH 8.0. The adsorption process was endothermic in nature. The experimental data fit well the Langmuir and Freundlich isotherms. Constants of the two isotherm equations were determined. Thermodynamic studies for the present process were performed by determining the values of ΔG°, ΔH°, and ΔS° at different temperatures. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800831v [article] Alumina nanoparticles for the removal of Ni(II) from aqueous solutions [texte imprimé] / Y. C. sharma, Auteur ; V. Srivastava, Auteur ; Upadhyay, S., Auteur . - 2008 . - p 8095–8100. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°21 (Novembre 2008) . - p 8095–8100 Mots-clés : Alumina  Nanoparticles Résumé : Alumina nanoparticles were developed by the sol−gel method and were used for the removal of Ni(II) ions from aqueous solutions. The nanoparticles were characterized by TEM and XRD. Nanoparticles of alumina were then used for removal of Ni(II) ions from aqueous solutions of nickel. The nanosize of the adsorbent was confirmed by TEM and XRD. Removal (%) was found to be dependent on the initial concentration of nickel, and maximum removal was found to be 96.6% at 25 mg/L Ni(II). The removal increased from 99 to 99.6% by decreasing the initial concentration from 75 to 25 mg/L. Equilibrium time was found to be 120 min. As expected, higher removal was obtained at higher adsorbent dose. The removal was governed by first-order kinetics, and the value of the rate constant of adsorption was found to be 1.83 × 10−2 min−1 at 25 mg/L and 25 °C. The removal was found to be pH dependent, and maximum removal was found to be at pH 8.0. The adsorption process was endothermic in nature. The experimental data fit well the Langmuir and Freundlich isotherms. Constants of the two isotherm equations were determined. Thermodynamic studies for the present process were performed by determining the values of ΔG°, ΔH°, and ΔS° at different temperatures. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800831v