REMOVAL OF PHENOLIC COMPOUNDS FROM AQUEOUS SOLUTIONS BY BIOSORPTION ONTO ACACIA LEUCOCEPHALA BARK POWDER: EQUILIBRIUM AND KINETIC STUDIES
REMOVAL OF PHENOLIC COMPOUNDS FROM AQUEOUS SOLUTIONS BY BIOSORPTION ONTO ACACIA LEUCOCEPHALA BARK POWDER: EQUILIBRIUM AND KINETIC STUDIES
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通过金合欢树皮粉末生物吸附去除水溶液中的酚类化合物：平衡和动力学研究
DOI：
10.4067/s0717-97072011000100004
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发表时间：
2011
影响因子：
1.6
通讯作者：
Kim Min
中科院分区：
文献类型：
--
作者：
Nadavala Siva Kumar;Kim Min
本研究的目的是确定金合欢树皮粉末作为生物吸附剂去除水中酚类化合物的潜在应用。实验考察了初始pH值（2 ~ 10）、接触时间、吸附质初始浓度（100 ~ 400 mg/L）和吸附剂用量的影响。在间歇平衡条件下，研究了树皮粉对苯酚、2-氯苯酚（2-CPh）和4-氯苯酚（4- cph）的吸附。pH 7.0时苯酚去除率最大。当pH值高于中性时，酚类化合物的吸附能力下降。吸附过程快速，接触时间为4 h即可达到吸附平衡。动力学研究表明，吸附过程符合准一级动力学模型。采用Langmuir、Freundlich和Dubinin-Radushkevich等温线模型对吸附平衡数据进行了分析。这些数据与朗缪尔等温线吻合得很好。Langmuir模型拟合最佳，对苯酚、2-CPh和4-CPh的最大吸附量分别为94.33、147.05和181.81 mg/g。结果表明，白桦树皮粉可作为较昂贵的吸附剂用于去除水中的酚类化合物。
The aim of this work is to determine the potential application of Acacia leucocephala bark powder as a biosorbent for removing phenolic compounds from aqueous solutions. Experiments were carried out as function of initial pH (2-10), contact time, initial concentration of adsorbate (100–400 mg/L), and effect of adsorbent dosage. Adsorption of phenolic compounds (phenol, 2-chlorophenol (2-CPh) and 4- chlorophenol (4-CPh)) from aqueous solutions on bark powder was studied under batch equilibrium conditions. Maximum phenol removal was observed at pH 7.0. Increase in the pH to above neutrality resulted in the decrease in the phenolic compounds adsorption capacity. The adsorption process was fast, and it reached equilibrium in 4-h contact time. The kinetics study demonstrated that the adsorption process proceeded according to the pseudo-first-order kinetic model. Three isotherm models (Langmuir, Freundlich and Dubinin-Radushkevich) were employed in the analysis of the adsorption equilibrium data. The data fitted well with the Langmuir isotherm. The Langmuir model resulted in the best fit and the new adsorbent had maximum adsorption capacities for phenol, 2-CPh and 4-CPh of 94.33, 147.05 and 181.81 mg/g, respectively. The results indicated that the A. leucocephala bark powder could be an alternative for more costly adsorbents used for removal of phenolic compounds from aqueous media.