Kinetic and thermodynamic studies for adsorptive removal of Sr2+ using waste iron oxide
Kinetic and thermodynamic studies for adsorptive removal of Sr2+ using waste iron oxide
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DOI：
10.1016/j.jtice.2013.08.012
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发表时间：
2014-05
影响因子：
5.7
通讯作者：
Chia-Hsun Liu;Yu-Jen Shih;Y. Huang;Chun-Ping Huang
中科院分区：
文献类型：
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作者：
Chia-Hsun Liu;Yu-Jen Shih;Y. Huang;Chun-Ping Huang
研究了从真实的流化床芬顿反应器中回收的铁氧化物BT 1对水中锶离子（Sr 2+）的吸附去除效果。毫米级BT 1（0.2-0.5 mm）主要由结晶不良的针铁矿相（α-FeOOH）组成，具有185 m2/g的比表面积。在10 ppm的初始Sr 2+水平下进行分批罐测试实验，以确定pH、吸附等温线、解吸过程和吸附动力学的影响。BT 1作为吸附剂去除Sr 2+的有效性强烈依赖于pH值;在平衡pH值为10.5时，5 g BT 1去除几乎100%的Sr 2+。Sr 2+被pH 3的硝酸溶液以相对低的速率解吸，并且回收的BT 1在至少三次吸附-解吸试验之后保持其高的吸附效率。吸附等温线用Langmuir和Freundlich模型均能准确描述，最大吸附量为38.46 mg/g。热力学参数揭示了吸附过程在20-45 °C的吸热和自发性质。动力学研究表明，BT 1对Sr ~（2+）的吸附为二级反应。
An iron oxide, BT1, recovered from a real fluidized-bed Fenton reactor, was studied to determine its effectiveness in the adsorptive removal of strontium ions (Sr2+) from water. Millimeter-scale BT1 (0.2–0.5 mm) mostly consisted of a poorly crystallized goethite phase (α-FeOOH), with a specific surface area of 185 m2/g. Batch jar-testing experiments were conducted at an initial Sr2+level of 10 ppm to determine the effect of pH, the adsorption isotherms, the desorption process, and the kinetics of adsorption. The effectiveness of BT1 as an adsorbent for the removal of Sr2+depended strongly on pH; at an equilibrium pH of 10.5, 5 g BT1 removed almost 100% of Sr2+. Sr2+was desorbed by a solution of nitric acid at pH 3 with a relatively low rate, and the recycled BT1 maintained its high adsorption efficiency after at least three adsorption–desorption tests. The isotherms were accurately described using both Langmuir and Freundlich models, and the maximum adsorption capacity was found to be 38.46 mg/g. The thermodynamic parameters revealed the endothermic and spontaneous nature of the adsorption process at 20–45 °C. Kinetic studies revealed that the adsorption of Sr2+ions on BT1 was a second-order reaction.