The role of natural organic matter in nitrite formation by LP-UV/H2O2 treatment of nitrate-rich water

File Description SizeFormat 
Manuscript.docxAccepted version69.13 kBMicrosoft WordView/Open
Supplementary Materials.docxSupporting information302.36 kBMicrosoft WordView/Open
Title: The role of natural organic matter in nitrite formation by LP-UV/H2O2 treatment of nitrate-rich water
Authors: Semitsoglou-Tsiapou, S
Mous, A
Templeton, MR
Graham, NJD
Hernandez Leal, L
Kruithof, JC
Item Type: Journal Article
Abstract: The role of natural organic matter (NOM) on nitrite formation from nitrate photolysis by low pressure ultraviolet lamp (LP-UV) photolysis and LP-UV/H2O2 treatment was investigated. Nitrate levels up to the WHO guideline maximum of 50 mg NO3−/L were used in tests. The presence of 4 mg/L Suwannee River natural organic matter (NOM) led to increased nitrite yields compared to NOM-free controls. This was caused partly by NOM scavenging of radical dotOH radicals, preserving the produced NO2− as well as the ONOO− that leads to NO2− formation, but also via the production of radical species (1O2, O2radical dot− and radical dotOH) by the photolysis of NOM. In addition, solvated electrons formed by NOM photolysis may reduce nitrate directly to nitrite. For comparison, Nordic Lake NOM, representative of aquatic NOM, as well as Pony Lake NOM, which had a greater nitrogen content (6.51% w/w) than the other two types of NOM, were investigated, yielding similar nitrite levels as Suwannee River NOM. The results suggest that neither the type nor the nitrogen content of the NOM have an effect on the nitrite yields obtained over the range of UV/H2O2 doses applied (UV fluences of 500–2100 mJ/cm2 and hydrogen peroxide doses of 10, 25, and 50 mg/L). The findings indicate that for UV fluences above 1500 mJ/cm2 the resulting nitrite concentration can exceed the 0.1 mg/L EU regulatory limit for nitrite, suggesting that nitrite formation by LP-UV advanced oxidation of nitrate-rich waters is important to consider.
Issue Date: 2-Oct-2016
Date of Acceptance: 2-Oct-2016
ISSN: 1879-2448
Publisher: Elsevier
Start Page: 312
End Page: 319
Journal / Book Title: Water Research
Volume: 106
Copyright Statement: © 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
Keywords: MD Multidisciplinary
Publication Status: Published
Appears in Collections:Faculty of Engineering
Civil and Environmental Engineering

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commons