Formation of haloacetamides during chlorination of dissolved organic nitrogen aspartic acid

Wen hai Chu, Nai yun Gao, Yang Deng

Research output: Contribution to journalArticlepeer-review

54 Scopus citations

Abstract

The stability of haloacetamides (HAcAms) such as dichloroacetamide (DCAcAm) and trichloroacetamide (TCAcAm) was studied under different experimental conditions. The yield of HAcAms during aspartic acid (Asp) chlorination was measured at different molar ratio of chlorine atom to nitrogen atom (Cl/N), pH and dissolved organic carbon (DOC) mainly consisted of humic acid (HA) mixture. Ascorbic acid showed a better capacity to prevent the decay of DCAcAm and TCAcAm than the other two dechlorinating agents, thiosulfate and sodium sulfite. Lower Cl/N favored the DCAcAm formation, implying that breakpoint chlorination might minimize its generation. The pH decrease could lower the concentration of DCAcAm but favored dichloroacetonitrile (DCAN) formation. DCAcAm yield was sensitive to the DOC due to higher chlorine consumption caused by HA mixture. Two possible pathways of DCAcAm formation during Asp chlorination were proposed. Asp was an important precursor of DCAN, DCAcAm and dichloroacetic acid (DCAA), and thus removal of Asp before disinfection may be a method to prevent the formation of DCAcAm, DCAN and DCAA.

Original languageEnglish
Pages (from-to)82-86
Number of pages5
JournalJournal of Hazardous Materials
Volume173
Issue number1-3
DOIs
StatePublished - 15 Jan 2010

Keywords

  • DON
  • Drinking water
  • Formation mechanism
  • Haloacetamides
  • N-DBPs

Fingerprint Dive into the research topics of 'Formation of haloacetamides during chlorination of dissolved organic nitrogen aspartic acid'. Together they form a unique fingerprint.

Cite this