Pressure-dependent criegee intermediate stabilization from alkene ozonolysis

Jani P. Hakala, Neil M. Donahue*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

33 Citations (Scopus)

Abstract

We explored the pressure dependence of acetone oxide (stabilized Criegee Intermediate, sCI) formation from 2,3-dimethyl-2-butene ozonolysis between 50 and 900 Torr using a new, highly accurate technique. We exploited the ability of the sCI to oxidize SO2 to H2SO4, which we measured with a chemical ionization mass spectrometer. We produced the Criegee intermediates (CI) in a high-pressure flow reactor via ozonolysis of 2,3-dimethyl-2-butene (tetramethyl ethylene, TME) and measured the relative H2SO4 concentrations with and without an added OH scavenger. Because the TME reaction with ozone forms acetone oxide (a syn-CI) with unit efficiency, we directly calculated the sCI yields at different pressures from the precisely measured ratio of the uncalibrated H2SO4 signal with and without the scavenger. We observed a linear pressure dependence between 50 and 900 Torr with a minimum stabilization of 12.7 ± 0.6% at 50 Torr and a maximum stabilization of 42 ± 2% at 900 Torr. A linear fit to the measured data points shows a zero-pressure intercept of 15 ± 2%, constraining the fraction of CI formed below the barrier for acetone oxide isomerization.

Original languageEnglish
Pages (from-to)2173-2178
JournalJournal of Physical Chemistry A
Volume120
Issue number14
DOIs
Publication statusPublished - 28 Apr 2016
MoE publication typeA1 Journal article-refereed

Funding

This research was supported by a grant from NASA (NNX12AE54G) with instrumentation provided by an NSF MRI grant (CBET0922643) and Academy of Finland Centre of Excellence Grants 1118615 and 272041.

Fingerprint

Dive into the research topics of 'Pressure-dependent criegee intermediate stabilization from alkene ozonolysis'. Together they form a unique fingerprint.

Cite this