Formation of organic chloramines during water disinfection - chlorination versus chloramination

Wontae Lee, Paul Westerhoff

Research output: Contribution to journalArticlepeer-review

94 Scopus citations


Many of the available studies on formation of organic chloramines during chlorination or chloramination have involved model organic nitrogen compounds (e.g., amino acids), but not naturally occurring organic nitrogen in water. This study assessed organic chloramine formation during chlorination and chloramination of 16 natural organic matter (NOM) solutions and 16 surface waters which contained dissolved organic nitrogen (DON). Chlorination rapidly formed organic chloramines within 10 min, whereas chloramination formed organic chloramination much more slowly, reaching the maximum concentration between 2 and 120 h after the addition of monochloramine into the solutions containing DON. The average organic chloramine formation upon addition of free chlorine and monochloramine into the NOM solutions were 0.78 mg-Cl2/mg-DON at 10 min and 0.16 mg-Cl2/mg-DON at 24 h, respectively. Organic chloramine formation upon chlorination and chloramination increased as the dissolved organic carbon/dissolved organic nitrogen (DOC/DON) ratio decreased (i.e., DON contents increased). Chlorination of molecular weight (10,000 Da) fractionated water showed that molecular weight of DON would not impact the amount of organic chloramines produced. Comparison of three different disinfection schemes at water treatment plants (free chlorine, preformed monochloramine, and chlorine/ammonia additions) indicated organic chloramine formation could lead to a possible overestimation of disinfection capacity in many chloraminated water systems that add chlorine followed by an ammonia addition to form monochloramine.

Original languageEnglish (US)
Pages (from-to)2233-2239
Number of pages7
JournalWater Research
Issue number8
StatePublished - May 2009


  • Chloramination
  • Chlorination
  • Disinfection
  • Organic chloramines
  • Organic nitrogen

ASJC Scopus subject areas

  • Ecological Modeling
  • Water Science and Technology
  • Waste Management and Disposal
  • Pollution


Dive into the research topics of 'Formation of organic chloramines during water disinfection - chlorination versus chloramination'. Together they form a unique fingerprint.

Cite this