School of Chemistry and Environmental Science, Henan Normal University, Henan Key aboratory for Environmental Pollution Control, Xinxiang 453007, PR China.
J Hazard Mater. 2011 Aug 15;192(1):411-8. doi: 10.1016/j.jhazmat.2011.05.038. Epub 2011 May 23.
A synthetic non-steroidal anti-inflammatory drug diclofenac is one of the most frequently detected pharmaceuticals in various water samples. One of the most important degradation processes relating to diclofenac is its photodegradation in the aquatic environment. This paper studies the kinetic model for diclofenac degradation in water and the variation of the photodegradation of diclofenac in the presence of different forms of nitrogen changes with different pE values in the aquatic environment under simulated sunlight. The results demonstrate that degradation pathways proceed via pseudo first-order kinetics in all cases and the photodegradation of diclofenac is the sum of the degradation by direct photolysis and self-sensitization. NO(3)(-) and NO(2)(-) have inhibiting effects on the photodegradation of diclofenac. The different forms of nitrogen changes with different pE values and this has a significant influence on the photodegradation of diclofenac. The results show that when NH(4)(+) and NO(2)(-) coexist in the aquatic environment, the inhibiting effect on the photodegradation diclofenac is less than the sum of the partial inhibiting effects. The results indicated that NO(2)(-) had an obvious antagonistic action for NH(4)(+). When NO(3)(-) and NO(2)(-) coexisted in the aquatic environment, a similar antagonistic action between NO(3)(-) and NO(2)(-) was observed.
一种合成的非甾体类抗炎药双氯芬酸是各种水样中检测到的最常见的药物之一。与双氯芬酸有关的最重要的降解过程之一是其在水环境中的光降解。本文研究了双氯芬酸在水中的降解动力学模型，以及在模拟阳光条件下，不同 pE 值下，水环境中不同形式的氮对双氯芬酸光降解的变化。结果表明，在所有情况下，降解途径均通过拟一级动力学进行，双氯芬酸的光降解是直接光解和自敏化降解的总和。NO(3)(-)和 NO(2)(-)对双氯芬酸的光降解有抑制作用。不同形式的氮随不同的 pE 值而变化，这对双氯芬酸的光降解有显著影响。结果表明，当 NH(4)(+)和 NO(2)(-)共存于水环境中时，对双氯芬酸光降解的抑制作用小于各部分抑制作用的总和。结果表明，NO(2)(-)对 NH(4)(+)有明显的拮抗作用。当 NO(3)(-)和 NO(2)(-)共存于水环境中时，观察到 NO(3)(-)和 NO(2)(-)之间存在类似的拮抗作用。
