Control of N-nitrosodimethylamine (NDMA) formation from N,N-dimethylhydrazine compounds by ozone-based advanced oxidation processes

Yang Song; Jianshan Peng; Kai Li; Sha Feng; Wen Qin; Jin Jiang; Jun Ma

doi:10.1016/j.jhazmat.2023.131374

Control of N-nitrosodimethylamine (NDMA) formation from N,N-dimethylhydrazine compounds by ozone-based advanced oxidation processes

J Hazard Mater. 2023 Jun 15:452:131374. doi: 10.1016/j.jhazmat.2023.131374. Epub 2023 Apr 6.

Authors

Yang Song¹, Jianshan Peng¹, Kai Li¹, Sha Feng¹, Wen Qin², Jin Jiang³, Jun Ma⁴

Affiliations

¹ School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
² School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China. Electronic address: qinwenhit@163.com.
³ Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, Guangdong 510006, China. Electronic address: jiangjinhit@126.com.
⁴ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.

PMID: 37030232
DOI: 10.1016/j.jhazmat.2023.131374

Abstract

N-nitrosodimethylamine (NDMA) is formed during ozonation of model compounds with dimethylhydrazine groups, such as daminozide (DMZ) and 2-furaldehyde 2,2-dimethylhydrazone (2-F-DMH) at pH 7 with yields of 100 % and 87 %, respectively. In this study, ozone/hydrogen peroxide (O₃/H₂O₂) and ozone/peroxymonosulfate (O₃/PMS) were investigated to control NDMA formation, and O₃/PMS (50-65 %) was more effective than O₃/H₂O₂ (10-25 %) with a ratio of H₂O₂ or PMS to O₃ of 8:1. The reaction of PMS or H₂O₂ to decompose ozone could not compete with the ozonation of model compound because of the high second-order rate constants of the ozonation of DMZ (5 ×10⁵ M^-1 s^-1) or 2-F-DMH (1.6 ×10⁷ M^-1 s^-1). The R_ct value of the sulfate radical (SO₄^•-) showed a linear relationship with NDMA formation, indicating that SO₄^•- significantly contributed to its control. NDMA formation could be further controlled by injecting small quantities of ozone numerous times to minimize the dissolved ozone concentration. The effects of tannic acid, bromide and bicarbonate on NDMA formation were also investigated during ozonation, O₃/H₂O₂, and O₃/PMS processes. Bromate formation was more pronounced in the O₃/PMS process than in the O₃/H₂O₂ process. Therefore, in practical applications of O₃/H₂O₂ or O₃/PMS processes, the generation of NDMA and bromate should be detected.

Keywords: Bromate; N,N-dimethylhydrazine; N-nitrosodimethylamine (NDMA); O(3)/H(2)O(2) process; O(3)/PMS process.