Tetracycline adsorption onto rice husk ash, an agricultural waste: Its kinetic and thermodynamic studies
Tetracycline adsorption onto rice husk ash, an agricultural waste: Its kinetic and thermodynamic studies
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四环素在农业废弃物稻壳灰上的吸附：动力学和热力学研究
DOI：
10.1016/j.molliq.2016.07.090
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发表时间：
2016-10-01
影响因子：
6
通讯作者：
Gao, Jay
中科院分区：
文献类型：
--
作者：
Chen, Yajun;Wang, Fenghe;Gao, Jay
作为农业废物，稻壳灰（RHA）有可能成为从水溶液中去除四环素（TC）的可行替代吸附剂。这项研究旨在探索RHA作为新的吸附剂的可行性，并了解其TC的吸附机制。在这项研究中还评估了TC的初始浓度，吸附时间，溶液pH和温度对RHA吸附性能的影响。发现RHA的TC去除效率与TC溶液的初始浓度有关。 TC浓度在其吸附过程的前60分钟内急剧下降，然后仅逐渐达到600分钟内达到平衡。 RHA吸附能力与溶液pH，温度和离子强度有关，尤其是在高pH值下。温度的升高导致吸附能力达到两倍以上。此外，低酸和高碱性溶液可以加速TC的吸附到RHA上。在这项研究中，达到8.37 mg/g的最高吸附能力比文献中报道的其他吸附剂高得多，这表明RHA是一种新的吸附剂。在描绘吸附行为时，Langmuir等温线模型是最合理的。伪二阶模型非常适合实验数据，这表明对吸附的物理和化学控制大多。此类发现可以作为扩展RHA对新领域的适用性的有用指南。 （c）2016 Elsevier B.V.保留所有权利。
As an agricultural waste, rice husk ash (RHA) has the potential to be a viable alternative adsorbent for the removal of tetracycline (TC) from aqueous solution. This study aims to explore its feasibility of RHA as a new adsorbent, and understand its adsorption mechanism for TC. Also assessed in this study are the influences of initial concentration of TC, adsorption time, solution pH and temperature on RHA adsorption performance. It is found that TC removal efficiency of RHA is related to the initial concentration of TC solution. TC concentration decreases sharply within the first 60 min in its adsorption process, and then only gradually, reaching the equilibrium within 600 min. RHA adsorption capacity is related to solution pH, temperature, and ion intensity, especially at a high pH value. A rise of 313 K in temperature caused the adsorption capacity to more than double. Furthermore, low-acid and high-alkaline solution can accelerate the adsorption of TC onto RHA. The highest adsorption capacity of 8.37 mg/g achieved in this study is much higher than other adsorbates reported in the literature, indicating the feasibility of RHA as a new adsorbent. The Langmuir isotherm model is the most reasonable in depicting the adsorption behavior. The pseudo second order model fits the experimental data nicely, suggesting a mostly physical and chemical control over the adsorption. Such findings can serve as a useful guide in expanding the applicability of RHA to new areas. (C) 2016 Elsevier B.V. All rights reserved.