Enthalpies of formation of isoprene’s major oxidation byproducts

Ochando-Pardo, Montserrat; Nebot–Gil, Ignacio; González‐Lafont, Àngels; Lluch, José M.

doi:10.1016/j.cplett.2005.04.105

Cited by 1 publication

(3 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Section 3.5.1). Table 6 summarises the BDEs calculated according to the incremental method of Benson (1976) 73 and adopted from Ochando-Pardo et al (2005) 74 as well as the calculated rate constant k calc = k H Â n H of a pure H abstraction reaction and the amount of k calc of the measured rate constant k 298K . Usually, small BDEs indicate larger rate constants for H abstraction reactions.…”

Section: Diffusion Limitmentioning

confidence: 99%

“…Looking at methyl vinyl ketone, the BDE calculated after Benson (1976) 73 indicates a hydrogen abstraction reaction for NO 3 and SO 4 À (100%). The BDE adopted from Ochando-Pardo et al (2005) 74 indicates a possible contribution of 50 and 14% for an H atom abstraction to the overall rate constant of methacrolein and methyl vinyl ketone for nitrate radical reactions, respectively. For SO 4 À , Ochando-Pardo's BDE indicates that the H abstraction is the most probable reaction mechanism for methacrolein, but only a 27% contribution of H abstraction is calculated for methyl vinyl ketone.…”

Section: Diffusion Limitmentioning

confidence: 99%

“…(2005) 74 and the possible amount of H abstraction reaction with the total measured rate constant. MACR = methacrolein, MVK = methyl vinyl ketone, MAA = methacrylic acid 79 Based on this, we are regarding the E HOMO for the unsaturated compounds investigated in the present studies valid as well.…”

Section: Diffusion Limitmentioning

confidence: 99%

See 2 more Smart Citations

Atmospheric aqueous phase radical chemistry of the isoprene oxidation products methacrolein, methyl vinyl ketone, methacrylic acid and acrylic acid – kinetics and product studies

Schöne

Schindelka

Szeremeta

et al. 2014

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Kinetic and mechanistic studies were conducted on the isoprene oxidation products methacrolein, methyl vinyl ketone, methacrylic and acrylic acid reacting with hydroxyl and nitrate radicals and sulfate radical anions in aqueous solution by use of the laser flash photolysis technique and a reversed-rate method for kinetics. High-performance liquid chromatography/mass spectrometry was applied for product analysis. The kinetic investigations show the highest reactivity of the hydroxyl radical followed by sulfate and nitrate radicals. For methacrolein and methyl vinyl ketone the following rate constants have been determined at 298 K: k(OH+methacrolein) = (9.4 ± 0.7) × 10(9) M(-1) s(-1), k(OH+methyl vinyl ketone) = (7.3 ± 0.5) × 10(9) M(-1) s(-1), k(NO3+methacrolein) = (4.0 ± 1.0) × 10(7) M(-1) s(-1), k(NO3+methyl vinyl ketone) = (9.7 ± 3.4) × 10(6) M(-1) s(-1), k(SO4(-)+methacrolein) = (9.9 ± 4.9) × 10(7) M(-1) s(-1) and k(SO4(-)+methyl vinyl ketone) = (1.0 ± 0.2) × 10(8) M(-1) s(-1). Temperature and pH dependencies of the reactions of OH, NO3 and SO4(-) with methacrolein, methyl vinyl ketone, methacrylic and acrylic acid as well as Arrhenius parameters have been obtained and discussed. Product studies were performed on the OH radical induced oxidation of methacrolein and methyl vinyl ketone. In the reaction of methacrolein + OH methylglyoxal and hydroxyacetone were identified as first oxidation products with yields of 0.099 and 0.162. Methylglyoxal was primarily produced in the oxidation of methyl vinyl ketone with a yield of 0.052. For both precursor compounds the formation of glycolaldehyde was observed for the first time with yields of 0.051 and 0.111 in the oxidation of methacrolein and methyl vinyl ketone, respectively. Furthermore, highly functionalised C4 compounds were determined from the oxidation of both precursor compounds, but for the first time for methyl vinyl ketone. Reaction schemes were developed based on known peroxyl radical reaction mechanisms. The aqueous phase conversion of the first generation isoprene oxidation products can potentially contribute to tropospheric aqueous phase budgets of important carbonyl and dicarbonyl components which are expected to be conducive to the formation of aqSOA.

show abstract

Section: Diffusion Limitmentioning

confidence: 99%

Section: Diffusion Limitmentioning

confidence: 99%