Far-UVC 222 nm Treatment: Effects of Nitrate/Nitrite on Disinfection Byproduct Formation Potential
Year: 2024
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Irradiation at far ultraviolet C (far-UVC) 222 nm by krypton chloride (KrCl*) excilamps can enhance microbial disinfection and micropollutant photolysis/oxidation. However, nitrate/nitrite, which absorbs strongly at 222 nm, may affect the formation of disinfection byproducts (DBPs). Herein, we evaluated model organic matter and real water samples and observed a substantial increase in the formation potential for trichloronitromethane (chloropicrin) (TCNM-FP), a nitrogenous DBP, by nitrate or nitrite after irradiation at 222 nm. At a disinfection dose of 100 mJ·cm –2, TCNM-FP of humic acids and fulvic acids increased from ∼0.4 to 25 and 43 μg·L –1, respectively, by the presence of 10 mg-N·L –1 nitrate. For the effect of nitrate concentration, the TCNM-FP peak was observed at 5–10 mg-N·L –1 . Stronger fluence caused a greater increase of TCNM-FP. Similarly, the increase of TCNM-FP was also observed for wastewater and drinking water samples containing nitrate. Pretreatment using ozonation and coagulation, flocculation, and filtration or the addition of H 2 O 2 can effectively control TCNM-FP. The formation potential of other DBPs was minorly affected by irradiation at 222 nm regardless of whether nitrate/nitrite was present. Overall, far-UVC 222 nm treatment poses the risk of increasing TCNM-FP of waters containing nitrate or nitrite at environmentally relevant concentrations and the mitigation strategies merit further research.
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Funders: National Science Foundation, U.S. Environmental Protection Agency, U.S. Department of Agriculture, North Dakota State University, North Dakota Established Program to Stimulate Competitive Research, Natural Resources Conservation Service, Division of Chemical, Bioengineering, Environmental, and Transport Systems, Division of Chemistry, Office of Experimental Program to Stimulate Competitive Research
Awards: G2022824254, G2786473102, G3480186644, G4440185551, G4597140403, G6144811627, Collaborative Research: Enhanced Photolysis and Advanced Oxidation Processes by Novel KrCl* (222 nm) Irradiation, G7016681928, Collaborative Research: Synergistic Actions of Peroxy Acids and Metals for Advanced Water Treatment: Delineating Multi-Oxidant Mechanisms, Collaborative Research: Enhanced Photolysis and Advanced Oxidation Processes by Novel KrCl* (222 nm) Irradiation, G992135848
OpenAlex ID: W4401510639