Zhang Jian, Li Yan, Zhang Chenglu, Jing Yuming
School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
J Hazard Mater. 2008 Feb 11;150(3):774-82. doi: 10.1016/j.jhazmat.2007.05.036. Epub 2007 May 16.
Arundo donax root carbon (ADRC), a new adsorbent, was prepared from Arundo donax root by carbonization. The surface area of the adsorbent was determined 158 m(2)/g by N(2) adsorption isotherm. Batch adsorption experiments were carried out for the removal of malachite green (MG) from aqueous solution using ADRC as adsorbent. The effects of various parameters such as solution pH (3-10), carbon dose (0.15-1.0 g/100ml) and initial MG concentration (10-100mg/l) on the adsorption system were investigated. The effective pH was 5-7 and the optimum adsorbent dose was found to be 0.6g/100ml. Equilibrium experimental data at 293, 303 and 313 K were better represented by Langmuir isotherm than Freundlich isotherm using linear and non-linear methods. Thermodynamic parameters such as DeltaG, DeltaH and DeltaS were also calculated. The negative Gibbs free energy change and the positive enthalpy change indicated the spontaneous and endothermic nature of the adsorption. The adsorption equilibrium time was 180 min. Adsorption kinetics was determined using pseudo-first-order model, pseudo-second-order model and intraparticle diffusion model. The results showed that the adsorption of MG onto ADRC followed pseudo-second-order model.
芦竹根炭（ADRC）是一种新型吸附剂，由芦竹根经碳化制备而成。通过N₂吸附等温线测定该吸附剂的比表面积为158 m²/g。以ADRC为吸附剂，进行了从水溶液中去除孔雀石绿（MG）的间歇吸附实验。研究了溶液pH值（3 - 10）、炭剂量（0.15 - 1.0 g/100ml）和初始MG浓度（10 - 100mg/l）等各种参数对吸附体系的影响。有效pH值为5 - 7，最佳吸附剂剂量为0.6g/100ml。采用线性和非线性方法，293、303和313 K下的平衡实验数据用Langmuir等温线比Freundlich等温线拟合效果更好。还计算了诸如ΔG、ΔH和ΔS等热力学参数。吉布斯自由能变化为负，焓变为正，表明吸附过程具有自发性和吸热性。吸附平衡时间为180分钟。用准一级模型、准二级模型和颗粒内扩散模型确定吸附动力学。结果表明，MG在ADRC上的吸附遵循准二级模型。
