Electrochemically enhanced adsorption of aniline on activated carbon fibers
Electrochemically enhanced adsorption of aniline on activated carbon fibers
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DOI：
10.1016/j.seppur.2005.12.011
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发表时间：
2006-07-15
影响因子：
8.6
通讯作者：
Zhao, Yazhi
中科院分区：
文献类型：
--
作者：
Han, Yanhe;Quan, Xie;Zhao, Yazhi
对于吸附分离过程，吸附速率和吸附容量是影响成本的两个重要因素。研究了活性炭纤维（ACF）的阳极极化作用对苯胺的吸附速率和容量的影响。研究了活性炭纤维对苯胺的电吸附动力学及影响吸附等温线的因素（偏压、电解质和pH）。苯胺在活性炭纤维上的吸附/电吸附符合准一级吸附动力学，吸附速率随偏压的增大而增大。电吸附等温线，表现出各种响应取决于偏压电位，电解质和pH值，遵循两个经典的Langmuir和Freundlich模型。用电吸附法从水溶液中吸附苯胺，可使吸附容量提高两倍。用扫描电镜（SEM）和傅里叶变换红外光谱（FT-IR）对初始和饱和ACF进行了表征。扫描电子显微镜（SEM）观察表明，活性炭纤维表面没有发生氧化，循环伏安法测试结果也证实了这一点。红外光谱表明，苯胺与活性炭纤维之间的相互作用主要是弱物理吸附，而不是化学吸附。这些实验结果表明，电化学极化可以有效地提高活性炭纤维对苯胺的吸附速率和容量，这可能是由于活性炭纤维与苯胺之间的亲和力增强，而不是活性炭纤维表面或溶液中的氧化。(c)2005 Elsevier B. V.保留所有权利。
For adsorptive separation processes, the adsorption rate and capacity are two important factors affecting the costs. This study describes the anodic polarization of activated carbon fibers (ACFs), which can enhance the adsorption rate and capacity of aniline. The electrosorption kinetics and the affecting factors (bias potential, electrolyte, and pH) of isotherms for aniline on ACFs were investigated. The adsorption/electrosorption of aniline on ACFs follow pseudo-first-order adsorption kinetics, and the adsorption rate improves with increasing bias potential. The electrosorption isotherms, which exhibit a variety of responses depending on bias potential, electrolyte and pH, follow the two classical models of Langmuir and Freundlich. With electrosorption of aniline from aqueous solution, a two-fold enhancement of adsorption capacity is achievable. The initial and saturated ACFs were characterized using scanning electron micrograph (SEM) and Fourier transform infrared spectroscopy (FT-IR). The SEM micrographs show that the surface of ACFs is not oxidized, which is also verified by cyclic voltammetry results. The FT-IR spectroscopy suggests that the interaction between aniline and ACFs is main weak physisorption instead of chemisorption. These experimental results suggest that the electrochemical polarization of ACFs can effectively improve the adsorption rate and capacity of aniline, which may be due to the enhanced affinity between aniline and ACFs instead of the oxidation on the surface of ACFs or in the solution. (c) 2005 Elsevier B.V. All rights reserved.