摘要
亚硝基二甲胺(NDMA)是在氯/氯胺消毒中发现的一种新型消毒副产物,具有强烈致癌性,引起人们广泛关注。然而,近年来在水处理中应用日益广泛的臭氧氧化工艺中也发现了NDMA的生成,给臭氧应用提出了挑战且可能对后续消毒工艺造成很大威胁。该文从生成情况、前体物、影响因素、生成机理4个方面介绍臭氧氧化过程中生成副产物NDMA的研究进展。总结了国内外臭氧氧化工艺中NDMA的生成情况;介绍了易与臭氧反应生成NDMA的前体物及其结构特征;归纳了影响臭氧氧化生成NDMA的因素,主要包括臭氧量、pH值、溴离子3个方面;重点评述前体物与臭氧反应生成NDMA路径,主要包括甲醛催化亚硝化、N_2O_4亚硝化和偏二甲肼(UDMH)3条路径;最后展望副产物NDMA在臭氧氧化工艺中生成的研究方向。
N-Nitrosodimethylamine(NDMA) is a new disinfection byproduct that has been found in chlorinated/chloraminated drinking waters, it attracts widespread concern due to the carcinogenic characteristic of NDMA. However, the formation of NDMA has also been found in the ozonation process, which might bring a challenge to the application of ozone and pose a great threat to the subsequent disinfection process. This paper summarized the occurrence, precursors, influencing factors as well as formation mechanisms of NDMA formation during ozonation. The formation of NDMA during ozonation at home and abroad was reviewed at first. Then the specific structures of precursors that react with ozone and generate NDMA easily were introduced. Factors(ozone dosages, p H and bromide ion) that affected NDMA formation in ozonation process were summa-rized and three NDMA formation mechanisms during ozonation, including: catalytic nitrosation of formaldehyde, N_2O_4 nitrification, indirect oxidation via unsym-dimethylhydrazine(UDMH) pathway, were discussed with emphasis. Finally, future re-search directions for NDMA formation during ozonation were prospected.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2017年第S2期34-38,共5页
Environmental Science & Technology
基金
国家自然基金青年项目(51508209)
中国博士后基金特别资助(2016T90595)
中国博士后基金面上项目(一等)(2015M580561)
福建省自然科学基金(2015J05102)
关键词
臭氧氧化
副产物
NDMA
影响因素
生成机理
ozonation
by-products
NDMA
influencing factors
formation mechanisms
