Kinetics of Oxidation of Iodide (I-) and Hypoiodous Acid (HOI) by Peroxymonosulfate (PMS) and Formation of Iodinated Products in the PMS/I-/NOM System
Kinetics of Oxidation of Iodide (I-) and Hypoiodous Acid (HOI) by Peroxymonosulfate (PMS) and Formation of Iodinated Products in the PMS/I-/NOM System
复制标题
过一硫酸盐 (PMS) 氧化碘化物 (I-) 和次碘酸 (HOI) 的动力学以及 PMS/I-/NOM 系统中碘化产物的形成
DOI：
10.1021/acs.estlett.6b00471
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发表时间：
2017
影响因子：
10.9
通讯作者：
Guan Chaoting
中科院分区：
文献类型：
--
作者：
Li Juan;Jiang Jin;Zhou Yang;Pang Su-Yan;Gao Yuan;Jiang Chengchun;Ma Jun;Jin Yixin;Yang Yi;Liu Guanqi;Wang Lihong;Guan Chaoting
在这项工作中，研究了过一硫酸盐 (PMS) 转化碘化物 (I–) 和次碘酸 (HOI) 的动力学，以及在天然有机物 (NOM) 存在的情况下潜在形成令人担忧的碘化产物。随着pH值从5增加到10，PMS与I–反应的表观二阶速率常数从1.01×103逐渐降低到3.86×102M–1s–1，而HOI的表观二阶速率常数从1.08×102急剧增加到7.90×104M–1s–1。所获得的 pH 依赖性速率曲线可以通过受 pH 影响的 PMS 和/或 HOI 形态的影响得到很好的解释。 PMS/I–/NOM 系统在较宽的 pH 范围内可形成大量的总有机碘 (TOI)。在类似条件下，PMS/I-/NOM 系统中形成的 TOI 水平通常高于 HOCl 中形成的 TOI 水平，但远低于 NH2Cl 中形成的 TOI 水平。此外，在 PMS 处理过程中，在模拟水中和真实水中都检测到了特定的碘仿 (IF) 和单碘乙酸 (MIAA)。这项工作首次证明了 PMS 水处理过程中可能形成令人担忧的碘化产物，这对其应用具有重要意义。
In this work, the kinetics of transformation of iodide (I–) and hypoiodous acid (HOI) by peroxymonosulfate (PMS) and potential formation of worrisome iodinated products in the presence of natural organic matter (NOM) were investigated. As the pH increased from 5 to 10, the apparent second-order rate constants of reaction of PMS with I–gradually decreased from 1.01 × 103to 3.86 × 102M–1s–1, while those for HOI increased dramatically from 1.08 × 102to 7.90 × 104M–1s–1. The obtained pH-dependent rate profiles were explained well by the effects of pH-affected speciation of PMS and/or HOI. Considerable amounts of total organic iodine (TOI) could be formed in the PMS/I–/NOM system over a wide pH range. Under similar conditions, the TOI levels formed in the PMS/I–/NOM system were generally higher than those formed in the case of HOCl but much lower than those formed in the case of NH2Cl. Also, specific iodoform (IF) and monoiodoacetic acid (MIAA) were detected in both simulated and authentic waters during treatment with PMS. This work for the first time demonstrates the potential formation of worrisome iodinated products during water treatment with PMS, and this has important implications for its application.