Related Experiment Video
Updated: Aug 16, 2026
Single-throughput Complementary High-resolution Analytical Techniques for Characterizing Complex Natural Organic Matter Mixtures
Published on: January 7, 2019
Modeling monochloramine loss in the presence of natural organic matter
Stephen E Duirk1, Bertrand Gombert, Jean-Philippe Croué
1Department of Civil and Environmental Engineering, University of Iowa, Iowa City, IA 52242-1527, USA. duirk.stephen@epa.gov
Abstract:
A comprehensive model describing monochloramine loss in the presence of natural organic matter (NOM) is presented. The model incorporates simultaneous monochloramine autodecomposition and reaction pathways resulting in NOM oxidation. These competing pathways were resolved numerically using an iterative process evaluating hypothesized reactions describing NOM oxidation by monochloramine under various experimental conditions. The reaction of monochloramine with NOM was described as biphasic using four NOM specific reaction parameters. NOM pathway 1 involves a direct reaction of monochloramine with NOM (k(doc1) = 1.05 x 10(4)-3.45 x 10(4) M(-1) h(-1)). NOM pathway 2 is slower in terms of monochloramine loss and attributable to free chlorine (HOCl) derived from monochloramine hydrolysis (k(doc2) = 5.72 x 10(5)-6.98 x 10(5) M(-1) h(-1)), which accounted for the majority of monochloramine loss. Also, the free chlorine reactive site fraction in the NOM structure was found to correlate to specific ultraviolet absorbance at 280 nm (SUVA280). Modeling monochloramine loss allowed for insight into disinfectant reaction pathways involving NOM oxidation. This knowledge is of value in assessing monochloramine stability in distribution systems and reaction pathways leading to disinfection by-product (DBP) formation.
More Related Videos
08:05Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
08:57Improving Infrared Spectroscopy Characterization of Soil Organic Matter with Spectral Subtractions
Published on: January 10, 2019
Related Concept Videos
00:49Gravimetry: Inorganic And Organic Precipitating Agents
01:202° Amines to N-Nitrosamines: Reaction with NaNO2
02:34Nucleophilic Substitution Reactions
In 1896, the German chemist Paul Walden discovered that he could interconvert pure enantiomeric (+) and (-) malic acids through a series of reactions. This conversion suggested the involvement of optical inversion during the substitution reaction. Further, in 1930, Sir Christopher Ingold described for the first time two different forms of nucleophilic substitution reactions, which are known as SN1 (nucleophilic substitution unimolecular) and SN2 (nucleophilic substitution...