谷壳对水中铜离子的吸附热力学及动力学研究

Thermodynamics and Kinetics of Copper Sorption by Rice Bran

应用低成本吸附剂谷壳去除溶液中的重金属铜离子。以间歇吸附的方式考察了溶液pH值、反应时间、反应温度、金属离子初始浓度等物理化学参数对吸附过程的影响。在pH为7.0、温度为328K、谷壳用量为4g/L时,溶液中铜离子达到最大吸附去除率。吸附过程符合Langmuir吸附等温模式。吸附热力学表明谷壳对Cu2+的吸附是自发的吸热反应。谷壳对Cu2+的吸附动力学模型能够较好地符合准二级动力学方程。

The removal of copper from aqueous solution by rice bran, a low-cost adsorbent, was studied. The copper retention experiments have been performed intermittently to study the influence of physico-chemical key parameters such as solution pH, reaction time and temperature, initial concentration of metal ion were considered. Copper ion removal efficiency attains its maximum rate at the circumstance of pH 7.0, reaction temperature 328 K, dosage of rice bran 4g/L. The equilibrium process conformed with the Langmuir isotherm model. Thermodynamics Study indicated that the enthalpy of sorption was endothermic and spontaneous. Good correlation coefficient was obtained for the pseudo second-order kinetic model.