Acetonitrile and N-Chloroacetamide Formation from the Reaction of Acetaldehyde and Monochloramine

Susana Y. Kimura, Trang Nha Vu, Yukako Komaki, Michael Jacob Plewa, Benito Jose Marinas

Research output: Contribution to journalArticle

Abstract

Nitriles and amides are two classes of nitrogenous disinfection byproducts (DBPs) associated with chloramination that are more cytotoxic and genotoxic than regulated DBPs. Monochloramine reacts with acetaldehyde, a common ozone and free chlorine disinfection byproduct, to form 1-(chloroamino)ethanol. Equilibrium (K1) and forward and reverse rate (k1,k-1) constants for the reaction between initial reactants and 1-(chloroamino)ethanol were determined between 2 and 30 °C. Activation energies for k1 and k-1 were 3.04 and 45.2 kJ·mol-1, respectively, and enthalpy change for K1 was -42.1 kJ·mol-1. In parallel reactions, 1-(chloroamino)ethanol (1) slowly dehydrated (k2) to (chloroimino)ethane that further decomposed to acetonitrile and (2) was oxidized (k3) by monochloramine to produce N-chloroacetamide. Both reactions were acid/base catalyzed, and rate constants were characterized at 10, 18, and 25 °C. Modeling for drinking water distribution system conditions showed that N-chloroacetamide and acetonitrile concentrations were 5-9 times higher at pH 9.0 compared to 7.8. Furthermore, acetonitrile concentration was found to form 7-10 times higher than N-chloroacetamide under typical monochloramine and acetaldehyde concentrations. N-chloroacetamide cytotoxicity (LC50 = 1.78 × 10-3 M) was comparable to dichloroacetamide and trichloroacetamide, but less potent than N,2-dichloroacetamide and chloroacetamide. While N-chloroacetamide was not found to be genotoxic, N,2-dichloroacetamide genotoxic potency (5.19 × 10-3 M) was on the same order of magnitude as chloroacetamide and trichloroacetamide.

Original languageEnglish (US)
Pages (from-to)9954-9963
Number of pages10
JournalEnvironmental Science and Technology
Volume49
Issue number16
DOIs
StatePublished - Jul 13 2015

Fingerprint

Acetaldehyde
acetaldehyde
disinfection
ethanol
Disinfection
Byproducts
ethane
Ethanol
enthalpy
activation energy
chlorine
drinking water
ozone
acid
Water distribution systems
Nitriles
Ethane
Ozone
Chlorine
modeling

ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry

Cite this

Acetonitrile and N-Chloroacetamide Formation from the Reaction of Acetaldehyde and Monochloramine. / Kimura, Susana Y.; Vu, Trang Nha; Komaki, Yukako; Plewa, Michael Jacob; Marinas, Benito Jose.

In: Environmental Science and Technology, Vol. 49, No. 16, 13.07.2015, p. 9954-9963.

Research output: Contribution to journalArticle

Kimura, Susana Y. ; Vu, Trang Nha ; Komaki, Yukako ; Plewa, Michael Jacob ; Marinas, Benito Jose. / Acetonitrile and N-Chloroacetamide Formation from the Reaction of Acetaldehyde and Monochloramine. In: Environmental Science and Technology. 2015 ; Vol. 49, No. 16. pp. 9954-9963.
@article{06199c80a6394e0a95cb395ce1ccbec9,
title = "Acetonitrile and N-Chloroacetamide Formation from the Reaction of Acetaldehyde and Monochloramine",
abstract = "Nitriles and amides are two classes of nitrogenous disinfection byproducts (DBPs) associated with chloramination that are more cytotoxic and genotoxic than regulated DBPs. Monochloramine reacts with acetaldehyde, a common ozone and free chlorine disinfection byproduct, to form 1-(chloroamino)ethanol. Equilibrium (K1) and forward and reverse rate (k1,k-1) constants for the reaction between initial reactants and 1-(chloroamino)ethanol were determined between 2 and 30 °C. Activation energies for k1 and k-1 were 3.04 and 45.2 kJ·mol-1, respectively, and enthalpy change for K1 was -42.1 kJ·mol-1. In parallel reactions, 1-(chloroamino)ethanol (1) slowly dehydrated (k2) to (chloroimino)ethane that further decomposed to acetonitrile and (2) was oxidized (k3) by monochloramine to produce N-chloroacetamide. Both reactions were acid/base catalyzed, and rate constants were characterized at 10, 18, and 25 °C. Modeling for drinking water distribution system conditions showed that N-chloroacetamide and acetonitrile concentrations were 5-9 times higher at pH 9.0 compared to 7.8. Furthermore, acetonitrile concentration was found to form 7-10 times higher than N-chloroacetamide under typical monochloramine and acetaldehyde concentrations. N-chloroacetamide cytotoxicity (LC50 = 1.78 × 10-3 M) was comparable to dichloroacetamide and trichloroacetamide, but less potent than N,2-dichloroacetamide and chloroacetamide. While N-chloroacetamide was not found to be genotoxic, N,2-dichloroacetamide genotoxic potency (5.19 × 10-3 M) was on the same order of magnitude as chloroacetamide and trichloroacetamide.",
author = "Kimura, {Susana Y.} and Vu, {Trang Nha} and Yukako Komaki and Plewa, {Michael Jacob} and Marinas, {Benito Jose}",
year = "2015",
month = "7",
day = "13",
doi = "10.1021/acs.est.5b01875",
language = "English (US)",
volume = "49",
pages = "9954--9963",
journal = "Environmental Science and Technology",
issn = "0013-936X",
publisher = "American Chemical Society",
number = "16",

}

TY - JOUR

T1 - Acetonitrile and N-Chloroacetamide Formation from the Reaction of Acetaldehyde and Monochloramine

AU - Kimura, Susana Y.

AU - Vu, Trang Nha

AU - Komaki, Yukako

AU - Plewa, Michael Jacob

AU - Marinas, Benito Jose

PY - 2015/7/13

Y1 - 2015/7/13

N2 - Nitriles and amides are two classes of nitrogenous disinfection byproducts (DBPs) associated with chloramination that are more cytotoxic and genotoxic than regulated DBPs. Monochloramine reacts with acetaldehyde, a common ozone and free chlorine disinfection byproduct, to form 1-(chloroamino)ethanol. Equilibrium (K1) and forward and reverse rate (k1,k-1) constants for the reaction between initial reactants and 1-(chloroamino)ethanol were determined between 2 and 30 °C. Activation energies for k1 and k-1 were 3.04 and 45.2 kJ·mol-1, respectively, and enthalpy change for K1 was -42.1 kJ·mol-1. In parallel reactions, 1-(chloroamino)ethanol (1) slowly dehydrated (k2) to (chloroimino)ethane that further decomposed to acetonitrile and (2) was oxidized (k3) by monochloramine to produce N-chloroacetamide. Both reactions were acid/base catalyzed, and rate constants were characterized at 10, 18, and 25 °C. Modeling for drinking water distribution system conditions showed that N-chloroacetamide and acetonitrile concentrations were 5-9 times higher at pH 9.0 compared to 7.8. Furthermore, acetonitrile concentration was found to form 7-10 times higher than N-chloroacetamide under typical monochloramine and acetaldehyde concentrations. N-chloroacetamide cytotoxicity (LC50 = 1.78 × 10-3 M) was comparable to dichloroacetamide and trichloroacetamide, but less potent than N,2-dichloroacetamide and chloroacetamide. While N-chloroacetamide was not found to be genotoxic, N,2-dichloroacetamide genotoxic potency (5.19 × 10-3 M) was on the same order of magnitude as chloroacetamide and trichloroacetamide.

AB - Nitriles and amides are two classes of nitrogenous disinfection byproducts (DBPs) associated with chloramination that are more cytotoxic and genotoxic than regulated DBPs. Monochloramine reacts with acetaldehyde, a common ozone and free chlorine disinfection byproduct, to form 1-(chloroamino)ethanol. Equilibrium (K1) and forward and reverse rate (k1,k-1) constants for the reaction between initial reactants and 1-(chloroamino)ethanol were determined between 2 and 30 °C. Activation energies for k1 and k-1 were 3.04 and 45.2 kJ·mol-1, respectively, and enthalpy change for K1 was -42.1 kJ·mol-1. In parallel reactions, 1-(chloroamino)ethanol (1) slowly dehydrated (k2) to (chloroimino)ethane that further decomposed to acetonitrile and (2) was oxidized (k3) by monochloramine to produce N-chloroacetamide. Both reactions were acid/base catalyzed, and rate constants were characterized at 10, 18, and 25 °C. Modeling for drinking water distribution system conditions showed that N-chloroacetamide and acetonitrile concentrations were 5-9 times higher at pH 9.0 compared to 7.8. Furthermore, acetonitrile concentration was found to form 7-10 times higher than N-chloroacetamide under typical monochloramine and acetaldehyde concentrations. N-chloroacetamide cytotoxicity (LC50 = 1.78 × 10-3 M) was comparable to dichloroacetamide and trichloroacetamide, but less potent than N,2-dichloroacetamide and chloroacetamide. While N-chloroacetamide was not found to be genotoxic, N,2-dichloroacetamide genotoxic potency (5.19 × 10-3 M) was on the same order of magnitude as chloroacetamide and trichloroacetamide.

UR - http://www.scopus.com/inward/record.url?scp=84939600055&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84939600055&partnerID=8YFLogxK

U2 - 10.1021/acs.est.5b01875

DO - 10.1021/acs.est.5b01875

M3 - Article

C2 - 26167888

AN - SCOPUS:84939600055

VL - 49

SP - 9954

EP - 9963

JO - Environmental Science and Technology

JF - Environmental Science and Technology

SN - 0013-936X

IS - 16

ER -