This work investigated the degradation of theophylline (TPL) of environmental concerns by ferrate (Fe(VI)) and the effect of Fe(VI) pre-oxidation on formation of disinfection by-products (DBPs) from TPL during subsequent chlorination. TPL exhibited an appreciable reactivity toward Fe(VI) with apparent second-order rate constants (k_app) ranging from 5.7 to 2480 M⁻¹ s⁻¹ in the pH range from 6 to10. The pH-dependence of k_app could be well simulated by a proposed kinetic model including the generation of an intermediate between Fe(VI) and TPL. A tentative transformation pathway was proposed including the hydroxylation of the imidazole ring as well as the cleavage of CN and CN bonds. The presence of humic acid (HA) apparently reduced the degradation rates of TPL with Fe(VI) even considering the competitive consumption for Fe(VI) by HA. A two channel model successfully explained the effect of HA on the TPL degradation by Fe(VI), where oxidation intermediate of TPL was either reduced back to parent by HA or irreversibly transformed to final products. Compared to direct chlorination of TPL, Fe(VI) pre-oxidation at low dosage enhanced the formation of carbonaceous disinfection by-products (C-DBPs, e.g., 1,1-dichloro-2-propanone, 1,1,1-trichloro-2-propanone, and dichloroacetic acid) during subsequent chlorination. However, a high dosage of Fe(VI) pre-oxidation could decrease the formation of C-DBPs and nitrogenous disinfection by-products (N-DBPs, e.g., dichloroacetonitrile, trichloronitromethane). The effectiveness of Fe(VI) for elimination of TPL in natural water was confirmed, and Fe(VI) pre-oxidation at high doses reduced the formation of DBPs in natural water during subsequent chlorination.

这项工作研究了高铁酸盐（Fe（VI））对茶碱（TPL）的环境影响，以及Fe（VI）预氧化对在随后的氯化过程中由TPL形成消毒副产物（DBPs）的影响。TPL对Fe（VI）表现出可观的反应性，在6至10的pH范围内，表观二级速率常数（k _app）为5.7至2480 M ^-1 s ^-1。可以通过提议的动力学模型很好地模拟k _app的pH依赖性，该动力学模型包括在Fe（VI）和TPL之间生成中间体。提出了一种初步的转化途径，包括咪唑环的羟基化以及C N和C的裂解N个债券。即使考虑到HA对Fe（VI）的竞争性消费，腐殖酸（HA）的存在也明显降低了TPL与Fe（VI）的降解率。两通道模型成功地解释了HA对Fe（VI）对TPL降解的影响，其中TPL的氧化中间体被HA还原回母体或不可逆地转化为最终产物。与直接氯化TPL相比，低剂量的Fe（VI）预氧化增强了含碳消毒副产物（C-DBPs，例如1,1-二氯-2-丙酮，1,1,1-三氯的形成）在随后的氯化反应中加入-2-丙酮和二氯乙酸）。但是，高剂量的Fe（VI）预氧化可减少C-DBP的形成和含氮消毒副产物（N-DBP，例如二氯乙腈，三氯硝基甲烷）。