Kinetic studies of ozone assisted low temperature oxidation of dimethyl ether in a flow reactor using molecular-beam mass spectrometry

Hao Zhao, Xueliang Yang, Yiguang Ju

Research output: Journal article publicationJournal articleAcademic researchpeer-review

62 Citations (Scopus)

Abstract

The ozone assisted low temperature oxidation chemistry of dimethyl ether (DME) from 400 K to 750 K has been investigated in the mixture of DME/O3/O2/He/Ar in an atmospheric-pressure flow reactor coupled with the molecular beam mass spectrometry (MBMS) sampling technique. The mole fraction of ozone was varied from 0 to 0.146% in the mixture to study its enhanced kinetic effect on DME oxidation. The mole fractions of DME, O2, O3, CH2O, H2O2, CO, CO2, and CH3OCHO were quantified as functions of temperature at a fixed total volumetric flow rate. The experimental results revealed that the presence of ozone dramatically enhances the low temperature DME oxidation. Numerical simulations using the existing kinetic models (Kurimoto's model (KM) (Kurimoto et al., 2015), Burke's model (BM) (Burke et al., 2015), and Wang's model (WM) (Wang et al., 2015)) with an ozone sub-mechanism over-predicted the DME oxidation significantly. The observed large discrepancies between models and experiments for DME, CH2O, O2 and CH3OCHO mole fractions suggested that there were large uncertainties in the branching ratios of two competing chain-propagation and chain-branching reaction pairs involving CH3OCH2O2 and CH2OCH2O2H radicals at low temperature.

Original languageEnglish
Pages (from-to)187-194
Number of pages8
JournalCombustion and Flame
Volume173
DOIs
Publication statusPublished - 1 Nov 2016
Externally publishedYes

Keywords

  • DME
  • Flow reactor
  • Low temperature chemistry
  • Molecular beam mass spectrometry
  • Ozone assisted oxidation

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Physics and Astronomy(all)

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