The kinetics and mechanisms of the degradation of sulfamethoxypyridazine (SMP) by an ultraviolet-activated persulfate (UV/PS) advanced oxidation process (AOP) and the formation of disinfection byproducts (DBPs) during subsequent chlorination were investigated in this study. The UV/PS process can significantly remove SMP through pseudo-first-order reaction kinetics. In a competitive kinetic experiment, the second-order rate constant of SMP with sulfate radical was determined to be 2.73 × 10¹⁰ M⁻¹ s⁻¹, while that with hydroxyl radical was 2.22 × 10¹⁰ M⁻¹ s⁻¹. Six major transformation products in SMP degradation were recognized by LC/MS/MS analysis. It was assumed that the degradation pathway of SMP involves the hydroxylation of the aromatic ring, cleavage of the sulfonamide bond, oxidation of the aniline moiety and elimination of SO₂. The impacts of persulfate dose, pH, anions (HCO₃^–, SO₄²⁻, and Br⁻) and humic acid (HA) concentration on SMP degradation efficiency and DBP formation during subsequent chlorination were also examined. SMP degradation was accelerated with increasing persulfate dose, HCO₃^– and Br^- concentration as well as decreasing pH and HA concentration. However, the amount of chloroform (CF) formed was reduced under a higher persulfate dosage and lower pH. In contrast, the amount of dichloroacetonitrile (DCAN) formed was enhanced under a higher persulfate dose and lower pH. Adding HA also increased the formation of both CF and DCAN. While, both HCO₃^– and SO₄^2– had little effects on the formation of CF and DCAN. The presence of Br^– had no significant effects on the bromine incorporation factors (BIFs) of trihalomethanes (THMs) and dihaloacetonitriles (DHANs). Raw water experiments showed that the UV/PS process could destroy SMP in natural water as well as control the formation of DBPs.

在本研究中，研究了通过紫外线活化的过硫酸盐（UV / PS）高级氧化过程（AOP）降解磺胺甲氧基哒嗪（SMP）的动力学和机理，以及后续氯化过程中消毒副产物（DBPs）的形成。UV / PS工艺可以通过拟一级反应动力学显着去除SMP。在竞争动力学实验中，硫酸根自由基的SMP二级速率常数确定为2.73×10 ¹⁰  M ^-1  s ^-1，而羟基自由基的SMP的二级速率常数为2.22×10 ¹⁰  M ^-1  s ^-1。LC / MS / MS分析识别出SMP降解的六种主要转化产物。据推测，SMP的降解途径涉及芳环的羟基化，磺酰胺键的裂解，苯胺部分的氧化和SO _2的消除。过剂量，pH值，阴离子的影响（HCO ₃ ^-，SO ₄ ^2-，和Br ^-还检查了在SMP降解效率和DBP的形成随后的氯化过程中和腐殖酸（HA）浓度）。SMP降解随过剂量，HCO加速₃ ^-和Br ^-浓度以及降低pH和HA浓度。但是，在较高的过硫酸盐剂量和较低的pH值下，形成的氯仿（CF）的量减少了。相反，在较高的过硫酸盐剂量和较低的pH值下，形成的二氯乙腈（DCAN）的量增加了。添加HA还增加了CF和DCAN的形成。而，无论是HCO ₃ ^-和SO ₄ ^2-对CF和DCAN的形成影响很小。BR的存在^-对三卤甲烷（三卤甲烷）和dihaloacetonitriles（DHANs）的溴结合因子（的BIF）不显著影响。原水实验表明，UV / PS工艺可以破坏天然水中的SMP并控制DBP的形成。