Adsorption of methylene blue by a high-efficiency adsorbent (polydopamine microspheres): Kinetics, isotherm, thermodynamics and mechanism analysis
Adsorption of methylene blue by a high-efficiency adsorbent (polydopamine microspheres): Kinetics, isotherm, thermodynamics and mechanism analysis
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DOI：
10.1016/j.cej.2014.07.101
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发表时间：
2015-01-01
影响因子：
15.1
通讯作者：
Xu, Qun
中科院分区：
文献类型：
--
作者：
Fu, Jianwei;Chen, Zhonghui;Xu, Qun
采用简易氧化聚合法制备了聚多巴胺(PDA)微球，并将其用作去除水溶液中阳离子染料亚甲基蓝(MB)的高效吸附剂。采用扫描电子显微镜、透射电子显微镜、傅立叶变换红外光谱、N-2吸附/脱附等温线、粒径和Zeta电位分析等手段对合成的PDA微球和FDA微球-MB(MB吸附FDA微球)体系进行了表征。系统地考察了初始溶液pH、温度、初始浓度和接触时间的影响。结果表明，该树脂在25℃时的吸附容量可达90.7 mg/g，吸附动力学符合准二级动力学模型。平衡吸附数据符合Langmuir等温式。热力学分析表明，吸附是吸热自发的，也是一个物理吸附过程。此外，还根据实验结果提出了可能的吸附机理。(C)爱思唯尔出版的2014年。
Polydopamine (PDA) microspheres were synthesized by a facile oxidative polymerization method and used as a high-efficiency adsorbent for the removal of a cationic dye (methylene blue, MB) from aqueous solution. Characterizations of the as-synthesized PDA microspheres and FDA microspheres-MB (MB absorbed FDA microspheres) systems were performed using several techniques such as SEM, TEM, FTIR, N-2 adsorption/desorption isotherms, particle size and zeta potential analysis. The effects of initial solution pH, temperature, initial concentration, and contact time were systematically investigated. Results showed the adsorption capacity at 25 degrees C could reach up to 90.7 mg/g. Besides, adsorption kinetics showed that the adsorption behavior followed the pseudo-second-order kinetic model. The equilibrium adsorption data fitted the Langmuir isotherm well. Thermodynamic analyses showed that the adsorption was endothermic and spontaneous, and it was also a physisorption process. In addition, the possible adsorption mechanism was also proposed based on the experimental results. (C) 2014 Published by Elsevier B.V.