Removal of tetracycline by electrocoagulation: Kinetic and isotherm modeling through adsorption
Removal of tetracycline by electrocoagulation: Kinetic and isotherm modeling through adsorption
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DOI：
10.1016/j.jece.2013.12.009
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发表时间：
2014-03
影响因子：
7.7
通讯作者：
Y. A. Ouaissa;M. Chabani;A. Amrane;A. Bensmaili
中科院分区：
文献类型：
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作者：
Y. A. Ouaissa;M. Chabani;A. Amrane;A. Bensmaili
抗生素和生长激素在人类和兽医中的使用对地表水和地下水的质量有重大影响。研究了电凝聚(EC)法去除一种应用广泛、在水中的溶解度高、残留毒性高且不具有生物降解性的抗生素的相关性。利用EC过程中产生的金属氢氧化物去除水溶液中的四环素(TC)。到目前为止，关于该物质的去除机理的知识还没有得到研究。实验在间歇式电化学反应器中进行，采用铝电极。TC的去除较快，在15min内达到平衡。考察了主要操作参数的影响，结果表明，无论初始浓度如何，在pH为3~10的范围内，最大的去除效率都保持在接近99%的水平，而在pH为2时，去除效率急剧下降(10%)。研究结果还表明，电流强度对水中TC的去除有很大影响。用等温线模型模拟了电凝聚的机理，结果表明，SIPS等温线与实验数据吻合较好，表明吸附分子的单层覆盖率，并假定了能量的准高斯分布，因为Toth模型也发现了很高的关联性。此外，吸附动力学研究表明，在不同的电流密度、pH和初始抗生素浓度下，EC的吸附过程遵循准二级动力学模型。
The use of antibiotics and growth hormones in human and veterinary medicine has a significant effect on the quality of surface and groundwater. The relevance of an electrocoagulation (EC) process for the removal of an antibiotic selected because of its wide application, high solubility in water, high residual toxicity and an absence of biodegradability, was examined in this study. Metal hydroxides generated during EC were used to remove tetracycline (TC) from aqueous solution. The knowledge regarding the removal mechanism of this substance has not been investigated up to now. Experiments were carried out in a batch electrochemical reactor using aluminum electrodes. The removal of TC was relatively fast and equilibrium was reached within 15 min. The effects of the main operating parameters were examined and showed that irrespective of the initial concentration and for pH ranging from 3 to 10, maximum removal efficiency remained close to 99%; while a sharp decrease was recorded at pH 2 (10% removal). The results of this study also showed that the removal of TC from water was strongly affected by the current intensity. The mechanism of electrocoagulation was modeled using isotherm models and showed that the Sips isotherm matched satisfactorily experimental data, suggesting monolayer coverage of adsorbed molecules and assumed a quasi-Gaussian distribution energy owing to the high correlation also found for the Toth model. In addition, adsorption kinetic studies showed that the EC process followed a pseudo-second-order kinetic model at the various current densities, pH and initial antibiotic concentrations considered.