کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
151293 | 456468 | 2011 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Adsorption of copper ion from its aqueous solution by a novel biosorbent Uncaria gambir: Equilibrium, kinetics, and thermodynamic studies Adsorption of copper ion from its aqueous solution by a novel biosorbent Uncaria gambir: Equilibrium, kinetics, and thermodynamic studies](/preview/png/151293.png)
In this paper, gambir was chemically modified into insoluble adsorbent (GA). The GA was characterized by FTIR, pHzpc, SEM, and BET. The effects of pH, adsorbent dosage, initial concentration of Cu2+ solution and contact time were studied. Batch experiments were performed with aqueous copper solutions of concentration 10 mg/L, at pH 5.0 and 0.30 g adsorbent. The experimental data was analyzed using pseudo-first order, pseudo-second order and Elovich kinetic models. The correlation coefficient calculated from pseudo-second order equation was higher than pseudo-first order and Elovich kinetic equations, indicating that equilibrium data fitted well with pseudo-second order model where adsorption process was chemisorptions. The adsorption equilibrium was well described by Langmuir isotherm model. The maximum adsorption capacity was found to be 9.950 mg/g at 333 K. The Gibbs free energy change, ΔG°, values were negative indicating that the process of Cu2+ ions adsorbed onto GA was spontaneous. The positive values of ΔH° and ΔS° suggested that the process of adsorption was endothermic at high temperature.
Journal: Chemical Engineering Journal - Volume 170, Issue 1, 15 May 2011, Pages 145–153