Department of Safety Environmental System Engineering, Dongguk University, Gyeongju, Republic of Korea.
Colloids Surf B Biointerfaces. 2012 Jun 1;94:125-32. doi: 10.1016/j.colsurfb.2012.01.048. Epub 2012 Feb 7.
Biosorption of 2,4,6-trichlorophenol (2,4,6-TCP) from aqueous solution by biomass prepared from Acacia leucocephala bark, an agricultural solid waste has been investigated in the present study. All the experiments are carried out by batch mode technique. The resulting biosorbent was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The effect of experimental parameters such as contact time, effect of pH (2-10), initial concentration of adsorbate (50-200 mg L(-1)) and amount of biosorbent dosage was evaluated. The removal was found to be pH dependent, and maximum removal was found to be at pH 5.0. The equilibrium time was found to be 3h. The biosorbent dose was increased, and the percentage removal of 2,4,6-TCP was increased, while the adsorption capacity at equilibrium q(e) (mg g(-1)) (amount of 2,4,6-TCP loaded per unit weight of adsorbent) decreased. Biosorption kinetic and isotherm studies showed the pseudo-second-order kinetics with a good correlation coefficient (R(2)=0.999), and both Langmuir and Freundlich isotherms were the best choices to describe the adsorption behaviors. The maximum monolayer biosorption capacity of A. leucocephala bark for 2,4,6-TCP was found to be 256.4 mg g(-1), at 30±1°C according to Langmuir model. This study demonstrated for the first time that the A. leucocephala bark could be an alternative for more costly adsorbents used for removal of 2,4,6-TCP from aqueous media.
本研究考察了从农业固体废物相思树皮制备的生物质对水溶液中 2,4,6-三氯苯酚（2,4,6-TCP）的吸附作用。所有实验均采用间歇式技术进行。所得生物吸附剂采用傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）技术进行了表征。考察了实验参数如接触时间、pH 值（2-10）、吸附质初始浓度（50-200mg/L）和生物吸附剂用量的影响。结果表明，去除率与 pH 值有关，最大去除率出现在 pH 5.0。平衡时间为 3h。随着生物吸附剂剂量的增加，2,4,6-TCP 的去除率增加，而平衡时的吸附容量 q(e)（mg g(-1)）（单位重量吸附剂上负载的 2,4,6-TCP 量）降低。吸附动力学和等温线研究表明，准二级动力学具有良好的相关性（R(2)=0.999），并且 Langmuir 和 Freundlich 等温线都是描述吸附行为的最佳选择。根据 Langmuir 模型，在 30±1°C 时，相思树皮对 2,4,6-TCP 的最大单层生物吸附容量为 256.4mg g(-1)。本研究首次表明，相思树皮可以替代更昂贵的吸附剂，用于从水介质中去除 2,4,6-TCP。
