针对天然水中腐植酸(HA)类溶解性有机物去除问题.采用多壁碳纳米管为吸附剂,在不同的pH值、吸附剂量、初始HA浓度下进行吸附动力学实验,用准二级速率方程拟合了动力学数据,其线性相关度在0.99以E,拟合得到的平衡吸附量为27mgtg,与实验结果(25.5 mg/g)基本一致.在25-50℃下进行了碳纳米管吸附腐植酸的等温吸附实验,以Langmuir模型拟合的平衡吸附量为29.7mg/g,与实验结果相近.用Clapeyron-Clausius与GibbsHelmholtz方程计算的自由能(△G)、焓(△H)、熵(△S)皆为负值,说明碳纳米管对腐植酸的吸附为放热熵减过程.碳纳米管的表面、管间隙、管内腔及管束之间形成的束聚孔为其有效吸附点位,腐植酸与碳纳米管间的π-π作用也是吸附的主要原因之一.
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