Adsorption potential of maize cob carbon for 2,4-dichlorophenol removal from aqueous solutions: Equilibrium, kinetics and thermodynamics modeling
Adsorption potential of maize cob carbon for 2,4-dichlorophenol removal from aqueous solutions: Equilibrium, kinetics and thermodynamics modeling
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DOI：
10.1016/j.cej.2008.07.020
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发表时间：
2009-04-15
影响因子：
15.1
通讯作者：
Yun, S. E.
中科院分区：
文献类型：
--
作者：
Sathishkumar, M.;Binupriya, A. R.;Yun, S. E.
研究了以玉米芯为原料制备的热活性碳对水溶液中2，4-二氯苯酚(2，4-DCP)的吸附性能。考察了接触时间、2，4-DCP初始浓度、pH值和温度对测定结果的影响。实验研究了4-DCP在吸附剂上的吸附动力学。非线性形式的伪二阶模型表现出较好的拟合度和良好的相关系数。采用了邦汉姆扩散模型和颗粒内扩散模型。采用非线性的Langmuir等温线模型，对吸附数据进行了较好的关联，结果表明，在250~500目的粒径范围内，2，4-DCP的最大吸附容量为17.94 mg/g。PH效应和解吸研究表明，吸附过程中存在化学吸附机理。热力学研究表明，2，4-DCP在玉米芯碳上的吸附更有利。测得玉米芯碳的吸附熵变为26.91J/(Kmo1)，吸附热变为6.78kJ/mo1。(C)2008爱思唯尔B.V.保留所有权利。
The present study deals with the adsorption potential of thermally activated carbon developed from maize cob for the removal of 2,4-dichlorophenol (2,4-DCP) from aqueous solutions. Studies were conducted to delineate the effects of contact time, 2,4-DCP initial concentration, pH and temperature. The kinetics of 4-DCP adsorption from a solution onto an adsorbent was explored experimentally. Non-linear form of pseudo-second-order model showed a better fit with good correlation co-efficient. Bangham's and intraparticle diffusion model were also used. Non-linear form of Langmuir isotherm model was applied and the data correlate well and the maximum adsorption capacity was found to be 17.94 mg/g for the particle size of 250-500 mu m. Acidic pH was favorable for the adsorption of 2,4-DCP. Studies on pH effect and desorption showed that chemisorption mechanism was involved in the adsorption process. Thermodynamic study showed that adsorption of 2,4-DCP on maize cob carbon is more favored. The change in entropy (AS,) and heat of adsorption (Delta H degrees) of maize cob carbon were estimated as 26.91 J/(K mol) and 6.78 kJ/mol, respectively. (C) 2008 Elsevier B.V. All rights reserved.