| 摘 要： | In this study, quaternized chitosan microspheres(QCMS) were prepared and its Cr(VI) removal potential was investigated. Batch experiments were conducted to examine kinetics, adsorption isotherm, p H effect,and thermodynamic parameters. Equilibrium was attained within 50 min and maximum removal of 97.34%was achieved under the optimum conditions at p H 5. Adsorption data for Cr(VI) uptake by the QCMS were analyzed according to Langmuir, Freundlich, and Temkin adsorption models. The maximum uptake of Cr(VI)was 39.1 mg·g~(-1). Thermodynamic parameters for the adsorption system were determinated at 293 K, 303 K,313 K and 323 K.(ΔH° = 16.08 k J·mol~(-1);ΔG° =- 5.84 to- 8.08 k J·mol~(-1)and ΔS° = 74.81 J·K~(-1)·mol~(-1)).So the positive values of both ΔH° and ΔS° suggest an endothermic reaction and increase in randomness at the solid–liquid interface during the adsorption. ΔG° values obtained were negative indicating a spontaneous adsorption process. The kinetic process was described by a pseudo-second-order rate equation very well. The results of the present study indicated that the QCMS could be considered as a potential adsorbent for Cr(VI) in aqueous solutions.
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