A temperature-dependent study of the ozonolysis of propene

R. S. Disselkamp, Michel Dupuis

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The ozonolysis of propene has been investigated in a temperature controlled reaction chamber at 295, 260, and 230 K. Experiments were performed using a total zero air pressure of 760 Torr (STP) and propene/ozone reactant mixing ratios ranging from 2.3 to 23 ppmv. An analysis of FTIR spectra collected at the conclusion of each reaction revealed that methane was formed with a yield of 0.14 ± 0.03 (precision) for all the temperatures investigated. In addition, the yield of HCHO decreased from 0.67 ± 0.04 to 0.43 ± 0.03 upon cooling from 295 to 230 K, whereas the yield of HCOOH increased from 0.11 ± 0.02 to 0.53 ± 0.04. Experiments were also performed using an excess of cyclohexane (to scavenge OH) and it was found that the formaldehyde yield was 0.79 ± 0.05 and 0.61 ± 0.04 at 295 and 260 K, respectively. Finally, to more fully understand the reaction energies involved in product formation, we have performed molecular orbital calculations of heats of formation of reactants, stable intermediates, and products. Three conclusions can be made of this work. First, the reaction CH2OO + Aldehyde → Secondary Ozonide → HCOOH + Aldehyde is not an important mechanism in formic acid production. Second, the decomposition of the primary ozonide products (e.g., C2 radical species) appears to occur, in part, by a thermal mechanism (e.g., thermalized to chamber temperature). Third, ab initio results combined with experiment reveal no correlation between reaction exothermicity and products formed (e.g., kinetically dictated product formation occurs). The ab initio database is provided nevertheless as a starting point for transition state calculations to be performed in the future. Finally, since formaldehyde yield decreases by at most ∼35% with decreasing temperature and formic acid is relatively unreactive in the atmosphere, our results suggest that temperature-dependent HCHO yield will constitute only a minor perturbation to HOx formation in the middle troposphere.

Original languageEnglish
Pages (from-to)231-245
Number of pages15
JournalJournal of Atmospheric Chemistry
Volume40
Issue number3
DOIs
Publication statusPublished - 2001

Fingerprint

formic acid
Aldehydes
temperature
Formaldehyde
aldehyde
formaldehyde
Temperature
Orbital calculations
Troposphere
Ozone
Experiments
Methane
Molecular orbitals
experiment
mixing ratio
atmospheric pressure
propylene
troposphere
Cooling
Decomposition

Keywords

  • Ab initio
  • Ozonolysis
  • Product yield
  • Propene

ASJC Scopus subject areas

  • Atmospheric Science
  • Environmental Science(all)
  • Environmental Chemistry

Cite this

A temperature-dependent study of the ozonolysis of propene. / Disselkamp, R. S.; Dupuis, Michel.

In: Journal of Atmospheric Chemistry, Vol. 40, No. 3, 2001, p. 231-245.

Research output: Contribution to journalArticle

@article{864db52327a445b1ba09ed4e8e156603,
title = "A temperature-dependent study of the ozonolysis of propene",
abstract = "The ozonolysis of propene has been investigated in a temperature controlled reaction chamber at 295, 260, and 230 K. Experiments were performed using a total zero air pressure of 760 Torr (STP) and propene/ozone reactant mixing ratios ranging from 2.3 to 23 ppmv. An analysis of FTIR spectra collected at the conclusion of each reaction revealed that methane was formed with a yield of 0.14 ± 0.03 (precision) for all the temperatures investigated. In addition, the yield of HCHO decreased from 0.67 ± 0.04 to 0.43 ± 0.03 upon cooling from 295 to 230 K, whereas the yield of HCOOH increased from 0.11 ± 0.02 to 0.53 ± 0.04. Experiments were also performed using an excess of cyclohexane (to scavenge OH) and it was found that the formaldehyde yield was 0.79 ± 0.05 and 0.61 ± 0.04 at 295 and 260 K, respectively. Finally, to more fully understand the reaction energies involved in product formation, we have performed molecular orbital calculations of heats of formation of reactants, stable intermediates, and products. Three conclusions can be made of this work. First, the reaction CH2OO + Aldehyde → Secondary Ozonide → HCOOH + Aldehyde is not an important mechanism in formic acid production. Second, the decomposition of the primary ozonide products (e.g., C2 radical species) appears to occur, in part, by a thermal mechanism (e.g., thermalized to chamber temperature). Third, ab initio results combined with experiment reveal no correlation between reaction exothermicity and products formed (e.g., kinetically dictated product formation occurs). The ab initio database is provided nevertheless as a starting point for transition state calculations to be performed in the future. Finally, since formaldehyde yield decreases by at most ∼35{\%} with decreasing temperature and formic acid is relatively unreactive in the atmosphere, our results suggest that temperature-dependent HCHO yield will constitute only a minor perturbation to HOx formation in the middle troposphere.",
keywords = "Ab initio, Ozonolysis, Product yield, Propene",
author = "Disselkamp, {R. S.} and Michel Dupuis",
year = "2001",
doi = "10.1023/A:1012239827705",
language = "English",
volume = "40",
pages = "231--245",
journal = "Journal of Atmospheric Chemistry",
issn = "0167-7764",
publisher = "Springer Netherlands",
number = "3",

}

TY - JOUR

T1 - A temperature-dependent study of the ozonolysis of propene

AU - Disselkamp, R. S.

AU - Dupuis, Michel

PY - 2001

Y1 - 2001

N2 - The ozonolysis of propene has been investigated in a temperature controlled reaction chamber at 295, 260, and 230 K. Experiments were performed using a total zero air pressure of 760 Torr (STP) and propene/ozone reactant mixing ratios ranging from 2.3 to 23 ppmv. An analysis of FTIR spectra collected at the conclusion of each reaction revealed that methane was formed with a yield of 0.14 ± 0.03 (precision) for all the temperatures investigated. In addition, the yield of HCHO decreased from 0.67 ± 0.04 to 0.43 ± 0.03 upon cooling from 295 to 230 K, whereas the yield of HCOOH increased from 0.11 ± 0.02 to 0.53 ± 0.04. Experiments were also performed using an excess of cyclohexane (to scavenge OH) and it was found that the formaldehyde yield was 0.79 ± 0.05 and 0.61 ± 0.04 at 295 and 260 K, respectively. Finally, to more fully understand the reaction energies involved in product formation, we have performed molecular orbital calculations of heats of formation of reactants, stable intermediates, and products. Three conclusions can be made of this work. First, the reaction CH2OO + Aldehyde → Secondary Ozonide → HCOOH + Aldehyde is not an important mechanism in formic acid production. Second, the decomposition of the primary ozonide products (e.g., C2 radical species) appears to occur, in part, by a thermal mechanism (e.g., thermalized to chamber temperature). Third, ab initio results combined with experiment reveal no correlation between reaction exothermicity and products formed (e.g., kinetically dictated product formation occurs). The ab initio database is provided nevertheless as a starting point for transition state calculations to be performed in the future. Finally, since formaldehyde yield decreases by at most ∼35% with decreasing temperature and formic acid is relatively unreactive in the atmosphere, our results suggest that temperature-dependent HCHO yield will constitute only a minor perturbation to HOx formation in the middle troposphere.

AB - The ozonolysis of propene has been investigated in a temperature controlled reaction chamber at 295, 260, and 230 K. Experiments were performed using a total zero air pressure of 760 Torr (STP) and propene/ozone reactant mixing ratios ranging from 2.3 to 23 ppmv. An analysis of FTIR spectra collected at the conclusion of each reaction revealed that methane was formed with a yield of 0.14 ± 0.03 (precision) for all the temperatures investigated. In addition, the yield of HCHO decreased from 0.67 ± 0.04 to 0.43 ± 0.03 upon cooling from 295 to 230 K, whereas the yield of HCOOH increased from 0.11 ± 0.02 to 0.53 ± 0.04. Experiments were also performed using an excess of cyclohexane (to scavenge OH) and it was found that the formaldehyde yield was 0.79 ± 0.05 and 0.61 ± 0.04 at 295 and 260 K, respectively. Finally, to more fully understand the reaction energies involved in product formation, we have performed molecular orbital calculations of heats of formation of reactants, stable intermediates, and products. Three conclusions can be made of this work. First, the reaction CH2OO + Aldehyde → Secondary Ozonide → HCOOH + Aldehyde is not an important mechanism in formic acid production. Second, the decomposition of the primary ozonide products (e.g., C2 radical species) appears to occur, in part, by a thermal mechanism (e.g., thermalized to chamber temperature). Third, ab initio results combined with experiment reveal no correlation between reaction exothermicity and products formed (e.g., kinetically dictated product formation occurs). The ab initio database is provided nevertheless as a starting point for transition state calculations to be performed in the future. Finally, since formaldehyde yield decreases by at most ∼35% with decreasing temperature and formic acid is relatively unreactive in the atmosphere, our results suggest that temperature-dependent HCHO yield will constitute only a minor perturbation to HOx formation in the middle troposphere.

KW - Ab initio

KW - Ozonolysis

KW - Product yield

KW - Propene

UR - http://www.scopus.com/inward/record.url?scp=0034754279&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034754279&partnerID=8YFLogxK

U2 - 10.1023/A:1012239827705

DO - 10.1023/A:1012239827705

M3 - Article

VL - 40

SP - 231

EP - 245

JO - Journal of Atmospheric Chemistry

JF - Journal of Atmospheric Chemistry

SN - 0167-7764

IS - 3

ER -