School of Pharmaceutical and Chemical Engineering, Taizhou University, Dongfang Road No 605, Linhai 317000, Zhejiang, PR China.
J Hazard Mater. 2010 May 15;177(1-3):228-36. doi: 10.1016/j.jhazmat.2009.12.022. Epub 2009 Dec 11.
In the present study, Cinnamomum camphora leaves powder (CLP) was investigated as a biosorbent for the removal of copper ions from aqueous solutions. The biosorbents before and after adsorption were measured by EDS and FT-IR. Kinetic data and sorption equilibrium isotherms were carried out in batch process. The adsorption kinetic experiments revealed that there are three stages in the whole adsorption process. It was found that Cu(II) adsorption onto CLP for different initial Cu(II) concentrations all followed pseudo-second order kinetics and were mainly controlled by the film diffusion mechanism. Batch equilibrium results at different temperatures suggest that Cu(II) adsorption onto CLP can be described perfectly with Langmuir isotherm model compared to Freundlich and D-R isotherm models, and the characteristic parameters for each adsorption isotherm were also determined. Thermodynamic parameters calculated show that the adsorption process has been found to be endothermic in nature. The analysis for the values of the mean free energies of adsorption (E(a)), the Gibbs free energy (DeltaG(0)) and the effect of ionic strength all demonstrate that the whole adsorption process is mainly dominated by ion-exchange mechanism, accompanied by a certain amount of surface complexation which has been verified by variations in EDS and FT-IR spectra and pH value before and after adsorption. Regeneration studies show CLP possesses an excellent reusability.
在本研究中，研究了肉桂叶粉（CLP）作为一种生物吸附剂，用于从水溶液中去除铜离子。用 EDS 和 FT-IR 对吸附前后的吸附剂进行了测量。在批处理过程中进行了动力学数据和吸附平衡等温线的研究。吸附动力学实验表明，整个吸附过程存在三个阶段。结果表明，对于不同初始 Cu(II)浓度，CLP 对 Cu(II)的吸附均符合拟二级动力学，主要受膜扩散机制控制。不同温度下的批平衡结果表明，与 Freundlich 和 D-R 等温模型相比，Cu(II)在 CLP 上的吸附可以用 Langmuir 等温模型很好地描述，并且还确定了每个吸附等温模型的特征参数。计算得到的热力学参数表明，吸附过程本质上是吸热的。对平均吸附自由能 (E(a))、吉布斯自由能 (DeltaG(0)) 和离子强度的影响的分析表明，整个吸附过程主要由离子交换机制主导，同时伴随着一定量的表面络合，这已通过吸附前后 EDS 和 FT-IR 光谱以及 pH 值的变化得到验证。再生研究表明 CLP 具有良好的可重复使用性。
