Oligomeric products and formation mechanisms from acid-catalyzed reactions of methyl vinyl ketone on acidic sulfate particles

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalNot applicablepeer-review

11 Scopus Citations
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Author(s)

  • Ka Man Chan
  • Dan Dan Huang
  • Yong Jie Li
  • Man Nin Chan
  • John H. Seinfeld

Detail(s)

Original languageEnglish
Pages (from-to)1-18
Journal / PublicationJournal of Atmospheric Chemistry
Volume70
Issue number1
Publication statusPublished - 2013
Externally publishedYes

Abstract

Methyl vinyl ketone (MVK) is a key first-generation product from atmospheric isoprene photo-oxidation, especially under high-NOx conditions. In this work, acid-catalyzed reactions of gas-phase MVK with ammonium sulfate (AS), ammonium bisulfate (ABS), and sulfuric acid (SA) particles were investigated in a flow reaction system at relative humidity (RH) of 40 % and 80 %. Ultra-performance liquid chromatography with electrospray ionization time-of-flight mass spectrometry (UPLC/ESI-TOFMS) and gas chromatography-mass spectrometry (GC-MS) are utilized to identify particle-phase products for developing the reaction mechanisms. High-order oligomers such as dimers and tetramers were detected when ABS and SA particles were used, while no oligomeric products were found when AS particles were used. Particle-phase oligomeric products were formed via i) acid-catalyzed aldol reaction with or without dehydration and/or ii) acid-catalyzed hydration followed by oligomerization. Reactions on SA particles yield more abundant and higher-order oligomers up to hexamers than on ABS particles. Moreover, aldol reaction occurred only on SA particles, but hydration followed by oligomerization occurred in both ABS and SA particles. The high RH condition with the same type of acidic particles was found to favor hydration and facilitate the subsequent oligomerization, while the low RH condition with the same type of acidic particles was found to favor aldol reaction with dehydration (aldol condensation). Overall, the findings suggest acidic particles can facilitate the formation of high-order oligomers in the particle phase, with particle acidity and RH as key factors. © 2013 Springer Science+Business Media Dordrecht.

Research Area(s)

  • Acid-catalyzed reaction, Aldol reaction, Methyl vinyl ketone, Oligomerization, Secondary organic aerosols

Citation Format(s)

Oligomeric products and formation mechanisms from acid-catalyzed reactions of methyl vinyl ketone on acidic sulfate particles. / Chan, Ka Man; Huang, Dan Dan; Li, Yong Jie; Chan, Man Nin; Seinfeld, John H.; Chan, Chak K.

In: Journal of Atmospheric Chemistry, Vol. 70, No. 1, 2013, p. 1-18.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalNot applicablepeer-review