College of Environment, Hohai University, 210098, Nanjing, China.
Key Laboratory of Integrated Regulation and Resource Development On Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.
Environ Sci Pollut Res Int. 2022 Mar;29(11):16517-16528. doi: 10.1007/s11356-021-16853-4. Epub 2021 Oct 14.
Dissolved organic nitrogen (DON) has been a research subject due to its potential to form nitrogenous disinfection byproducts (N-DBPs) in drinking water treatment. In our study, CoFe layered double oxide (CoFe-LDO) was selected as an effective catalyst for the removal of histidine by activation of peroxymonosulfate (PMS). The results investigated that the removal of DON and histidine within 1 h in the CoFe-LDO/PMS system were up to 61% and 72%, respectively. The influences of CoFe-LDO dosage, PMS dosage, and pH value for DON removal were also elucidated. The optimum pH was 8, and the optimal dosage of CoFe-LDO and PMS were 0.04 g/L and 0.5 mmol/L. It was found that SO and •OH induced by the transformation of Co-Co and Fe-Fe on the catalyst surface were responsible for the degradation by ESR detection, in which SO played a more important role. The degradation pathway of histidine indicated that it was partly oxidized to NH-N in the 60 min and no evident generation of N during the whole process. Furthermore, degradation products of histidine have also been revealed by the analysis of HPLC-MS. In addition, the generation potentials of two typical N-DBPs were also clarified. The formation potential of dichloroacetonitrile (DCAN) decreased, while that of dichloroacetamide (DCAcAm) increased firstly before declining.
溶解态有机氮（DON）因其在饮用水处理中形成含氮消毒副产物（N-DBPs）的潜力而成为研究课题。在我们的研究中，CoFe 层状双氢氧化物（CoFe-LDO）被选为一种有效催化剂，通过激活过一硫酸盐（PMS）来去除组氨酸。结果表明，在 CoFe-LDO/PMS 体系中，DON 和组氨酸在 1 小时内的去除率分别高达 61%和 72%。还研究了 CoFe-LDO 用量、PMS 用量和 pH 值对 DON 去除的影响。最佳 pH 值为 8，CoFe-LDO 和 PMS 的最佳用量分别为 0.04 g/L 和 0.5 mmol/L。通过 ESR 检测发现，催化剂表面 Co-Co 和 Fe-Fe 的转化诱导产生的 SO 和 •OH 是降解的原因，其中 SO 起更重要的作用。组氨酸的降解途径表明，它在 60 分钟内部分氧化为 NH-N，整个过程中没有明显的 N 生成。此外，还通过 HPLC-MS 分析揭示了组氨酸降解产物。此外，还澄清了两种典型 N-DBPs 的生成潜力。二氯乙腈（DCAN）的生成潜能降低，而二氯乙酰胺（DCAcAm）的生成潜能先增加后降低。
