Zhong Xin, Cui Chongwei, Yu Shuili
School of Municipal & Environmental Engineering, Harbin Institute of Technology, No. 73, Huanghe Road, Nangang District, Harbin, Heilongjiang Province, China.
School of Environmental Science and Engineering, Tongji University, Shanghai, 200433, China.
Environ Sci Pollut Res Int. 2017 Mar;24(7):6472-6480. doi: 10.1007/s11356-016-8350-1. Epub 2017 Jan 10.
Ozonation of fulvic acid (FA) can result in diverse intermediate oxidation by-products, significantly affecting disinfection by-product (DBP) formation following chlorination. The objective of this study was to provide insight into ozone reaction intermediates and reveal the possible formation pathway of DBPs from ozonation of FA due to the formation of intermediate oxidation by-products. Aldehydes, aromatic acids, short-chain acids, chloroform, and dichloroacetic acid were detected at various ozone dosage additions. Aromatic acids were studied by using solid-phase extraction-ultra high-performance liquid chromatography (SPE-UPLC). This new analytical approach enables the extraction and analysis of highly polar carboxylic acids that are difficult to measure using conventional methods. The results showed that formaldehyde, acetaldehyde, glyoxal, methyl-glyoxal, fumaric, malonic protocatechuic, 3-hydroxybenzoic, and benzoic acid were predominant oxidation by-products. The yields of the four aldehydes increased steadily with ozone dosage. When ozone dosage was 2∼2.5 mg/l, the amount of carboxylic acids was largest, and the total amount of the carboxylic acids was about 5∼10 times higher than that of the aldehydes. Besides, hydroxybenzoic acids are the major precursor, although they have low content in ozone reaction solution, they have a great contribution to the DBP formation. This study provides a new perspective on ozonation natural organic matter, which contributes to understand the other sources of DBPs and thus broadens the knowledge of drinking water treatment.
富里酸（FA）的臭氧化会产生多种中间氧化副产物，显著影响后续氯化过程中消毒副产物（DBP）的形成。本研究的目的是深入了解臭氧反应中间体，并揭示由于中间氧化副产物的形成，富里酸臭氧化过程中消毒副产物可能的形成途径。在添加不同臭氧剂量的情况下，检测到了醛类、芳香酸、短链酸、氯仿和二氯乙酸。采用固相萃取 - 超高效液相色谱法（SPE - UPLC）对芳香酸进行了研究。这种新的分析方法能够萃取和分析使用传统方法难以测量的高极性羧酸。结果表明，甲醛、乙醛、乙二醛、甲基乙二醛、富马酸、丙二酸、原儿茶酸、3 - 羟基苯甲酸和苯甲酸是主要的氧化副产物。四种醛类的产率随臭氧剂量稳步增加。当臭氧剂量为2∼2.5 mg/l时，羧酸的量最大，且羧酸的总量比醛类的总量高约5∼10倍。此外，羟基苯甲酸是主要前体，尽管它们在臭氧反应溶液中的含量较低，但对消毒副产物的形成有很大贡献。本研究为天然有机物的臭氧化提供了新的视角，有助于理解消毒副产物的其他来源，从而拓宽了饮用水处理的知识范围。
