Unexpected Role of Nitrite in Promoting Transformation of Sulfonamide Antibiotics by Peracetic Acid: Reactive Nitrogen Species Contribution and Harmful Disinfection Byproduct Formation Potential

Abstract

Peracetic acid (PAA) is an emerging oxidant and disinfectant for wastewater (WW) treatment due to limited harmful disinfection byproduct (DBP) formation. Nitrite (NO2 –) is a ubiquitous anion in water, but the impact of NO2 – on PAA oxidation and disinfection has been largely overlooked. This work found for the first time that NO2 – could significantly promote the oxidation of sulfonamide antibiotics (SAs) by PAA. Unexpectedly, the reactive nitrogen species (RNS), for example, peroxynitrite (ONOO–), rather than conventional organic radicals (R–O•) or reactive oxygen species (ROS), played major roles in SAs degradation. A kinetic model based on first-principles was developed to elucidate the reaction mechanism and simulate reaction kinetics of the PAA/NO2 – process. Structural activity assessment and quantum chemical calculations showed that RNS tended to react with an aromatic amine group, resulting in more conversion of NO2 –-N to organic-N. The formation of nitrated and nitrosated byproducts and the enhancement of trichloronitromethane formation potential might be a prevalent problem in the PAA/NO2 – process. This study provides new insights into the reaction of PAA with NO2 – and sheds light on the potential risks of PAA in WW treatment in the presence of NO2 –.

Reactive Nitrogen Species Mediated Inactivation of Pathogenic Microorganisms during UVA Photolysis of Nitrite at Surface Water Levels

“…The model-simulated steady-state concentrations of NO • , NO 2 • , and ONOOH/ONOO – were 3.76 × 10 –8 , 8.16 × 10 –9 , and 3.43 × 10 –10 M, respectively, which were much higher than the concentrations of ROS. Moreover, RNS was reported to be reactive toward the biomolecules like amino acids (e.g., k NO 2 • ‑tyrosine = 2.9 × 10 7 M –1 s –1 ). , The high concentrations and reactivities of RNS toward biomolecules suggested that their contributions to bacterial inactivation were potentially significant.…”

“…Moreover, RNS was reported to be reactive toward the biomolecules like amino acids (e.g., k NOd 2 • -tyrosine = 2.9 × 10 7 M −1 s −1 ). 38,42 The high concentrations and reactivities of RNS toward biomolecules suggested that their contributions to bacterial inactivation were potentially significant.…”

Emerging investigator series: contributions of reactive nitrogen species to transformations of organic compounds in water: a critical review

“…The reaction pathway did not involve reactions with ˙NO or ˙NO 2 based on scavenging experiments using flavonoids and tyrosine as scavengers, indicating that reactions involving ONOO − may have been responsible for sulfonamide nitr(os)ation in this system. 114…”

“…151,152 Similarly, cNO donor molecules, such as diethylamine NONOate (DEA-NONO) have been used to generate cNO and N 2 O 3 in the absence of cNO 2 . 152 In combination with the use of scavengers, such as avonoids, 114 these techniques may enable a more complete understanding of RNS relevant to reactions with DOM and trace organic contaminants.…”

UV 222 nm Emission from KrCl* Excimer Lamps Greatly Improves Advanced Oxidation Performance in Water Treatment

“…This UV/AOP generates hydroxyl radicals via hydrogen peroxide photolysis, which react rapidly (rate constants of 10 7 –10 10 M –1 s –1 ) and nonselectively with many organic and inorganic contaminants. , In recent years, the UV-driven production of hydroxyl radicals from species other than hydrogen peroxide has generated interest. AOPs that use chlorine (UV/Cl 2 or UV/NH 2 Cl) − or peroxydisulfate (UV/PDS) , as the radical promoter are increasingly being studied and, in some cases, employed at pilot or full scale. − Additionally, water matrix constituents such as nitrate or iron can create de facto AOPs when exposed to UV light. − Nitrate absorbs light very strongly at wavelengths below 240 nm to produce hydroxyl and other radicals and has demonstrated potential as a radical promoter in UV/AOP systems that utilize light sources emitting at far-UVC (200–230 nm) wavelengths. − …”