Pang Hui-Ling, Yang Gui-Peng, Gao Xian-Chi, Cao Xiao-Yan
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
Huan Jing Ke Xue. 2012 Jan;33(1):129-34.
The adsorption behaviors of norfloxacin (NOR) on marine sediments at different pH values and in the presence of four different surfactants were systematically investigated by a batch equilibrium method. The results indicated that Freundlich adsorption isotherms fitted the adsorption behavior of NOR on marine sediments very well at different pH values. The Freundlich constant K(F) and the equilibrium adsorption amount of NOR reduced with the increase of pH values, and the minimum appeared at pH 8.10. The results suggested that cation exchange was the main adsorption mechanism of NOR at pH 6.01, while Van der Waals' force, hydrophobic effects, electrostatic force were the major adsorption mechanism of NOR on marine sediments at pH 8.10. The adsorption process fitted well with pseudo-second-order kinetic equations with the addition of surfactants. Our study also indicated that the addition of surfactants had the significant influence on the saturated adsorption amount of adsorption of NOR. The equilibrium adsorption amount (Q(e)) of NOR exhibited the following sequence: Q(e) (Tween80) < Q(e) (Tween20) <Q(e)(No) < Q(e) (CTAB) < Q(e)(SDBS).
采用批量平衡法系统研究了诺氟沙星（NOR）在不同pH值以及四种不同表面活性剂存在下在海洋沉积物上的吸附行为。结果表明，Freundlich吸附等温线在不同pH值下能很好地拟合NOR在海洋沉积物上的吸附行为。Freundlich常数K(F)和NOR的平衡吸附量随pH值升高而降低，在pH 8.10时达到最小值。结果表明，阳离子交换是pH 6.01时NOR的主要吸附机制，而范德华力、疏水作用、静电力是pH 8.10时NOR在海洋沉积物上的主要吸附机制。添加表面活性剂后，吸附过程很好地符合准二级动力学方程。我们的研究还表明，表面活性剂的添加对NOR的饱和吸附量有显著影响。NOR的平衡吸附量（Q(e)）表现出以下顺序：Q(e)（吐温80）< Q(e)（吐温20）<Q(e)(无)< Q(e)（十六烷基三甲基溴化铵）< Q(e)(十二烷基苯磺酸钠) 。
