School of Environment, Henan Normal University, Henan Key Laboratory for Environmental Pollution Control, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Xinxiang 453007, PR China; School of Basic Medicine, Xinxiang Medical University, Xinxiang 453003, PR China.
School of Environment, Henan Normal University, Henan Key Laboratory for Environmental Pollution Control, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Xinxiang 453007, PR China.
Sci Total Environ. 2015 Feb 15;506-507:252-8. doi: 10.1016/j.scitotenv.2014.10.114. Epub 2014 Nov 20.
The reaction kinetics and toxicity of diclofenac (DCF) oxidation by ferrate (VI) under simulated water disinfection conditions were investigated. Experimental results indicated that the reaction between DCF and Fe(VI) followed first-order kinetics with respect to each reactant. Furthermore, the effects of pH and temperature on DCF oxidation by Fe(VI) were elucidated using a systematic examination. The apparent second-order rate constants (kapp) increased significantly from 2.54 to 11.6M(-1)s(-1), as the pH of the solution decreased from 11.0 to 7.0, and the acid-base equilibriums of Fe(VI) and DCF were proposed to explain the pH dependence of kapp. The acute toxicity of DCF solution during Fe(VI) oxidation was evaluated using a Microtox bioassay. Overall, the DCF degradation process resulted in a rapid increase of the inhibition rate of luminescent bacteria. These toxicity tests suggest that the formation of enhanced toxic intermediates during the Fe(VI) disinfection process may pose potential health risk to consumers.
六价铁（Fe(VI)）氧化二氯芬酸（DCF）的反应动力学和毒性在模拟水消毒条件下进行了研究。实验结果表明，DCF 与 Fe(VI)之间的反应对每种反应物均遵循一级动力学。此外，通过系统的考察阐明了 pH 值和温度对 Fe(VI)氧化 DCF 的影响。当溶液的 pH 值从 11.0 降低到 7.0 时，表观二级速率常数（kapp）从 2.54 显著增加到 11.6M(-1)s(-1)，并提出了 Fe(VI)和 DCF 的酸碱平衡来解释 kapp 的 pH 值依赖性。采用 Microtox 生物测定法评估了 Fe(VI)氧化过程中二氯芬酸溶液的急性毒性。总体而言，DCF 降解过程导致发光细菌的抑制率迅速增加。这些毒性测试表明，在 Fe(VI)消毒过程中形成的增强毒性中间产物可能对消费者构成潜在的健康风险。
