Atmospheric Reactivity of Vinyl Acetate: Kinetic and Mechanistic Study of Its Gas-Phase Oxidation by OH, O₃, and NO₃

Abstract

Vinyl acetate is widely used in industry. It has been classified as a high-production volume (HPV) chemical in the United States. To evaluate its impact on the environment and air quality, its atmospheric reactivity toward the three main tropospheric oxidants (OH, NO(3), and O(3)) has been investigated. Kinetic and mechanistic experiments have been conducted at room temperature and atmospheric pressure using an indoor Pyrex simulation chamber coupled to Fourier transform infrared (FTIR) and UV-visible spectrometers. Rate constants for the reactions of vinyl acetate with OH, NO(3), and O(3) were equal to (2.3 +/- 0.3) x 10(-11), (7.3 +/- 1.8) x 10(-15), and (3.0 +/- 0.4) x 10(-18) cm(3) molecule(-1) s(-1), respectively. From these data, tropospheric lifetimes of vinyl acetate have been estimated as follows: tau(OH) = 6 h, tau(NO(3)) = 6 days, and tau(O(3)) = 5 days. This demonstrates that reaction with OH radicals is the main tropospheric loss process of this compound. From the mechanistic experiments, main oxidation products have been identified and quantified and oxidation schemes have been proposed for each studied reaction.

Prediction of Rate Constants for Gas‐Phase Reactions of Nitrate Radical with Organic Compounds: A New Structure–Activity Relationship

“…Hence, the factors G(C(O)OR) and G(OC(O)R) were calculated and are presented in Table 5. The G(OC(O)R) were determined by using the rate constants obtained in recent studies on the reactions of vinyl acetate [72] and isopropenyl acetate [73] with NO 3 radical. The substituent factor for the effect of a ÀCOC(O)R group in b position was also calculated.…”

“…[b] Ref. [72], rate constants re-evaluated with k propene = 8.93 10 À15 cm 3 molecule À1 s À1 [37] at 293 K.…”

Theoretical Study of Reactions between Oxygen-Centered Radicals (•OH and SO4•-) and Vinyl Monomers in Aqueous Phase

“…However, hybrid and meta‐hybrid functionals such as B3LYP and M06‐2X provide a large improvement, particularly the M06‐2X functional, which exhibits an excellent performance on the calculation of standard thermochemistry properties . Results in Table show consistent agreement with experimental values . Calculations of rate coefficients for reactions between other vinyl monomers and • OH can be performed with confidence following the M06‐2X/6‐311++G (3df, 2p)//B3LYP/6‐31+G (d, p) scheme proposed in this work.…”

“…[ 23 ] Results in Table 1 show consistent agreement with experimental values. [29][30][31][32] Calculations of rate coeffi cients for reactions between other vinyl monomers and • OH can be performed with confi dence following the M06-2X/6-311++G (3df, 2p)//B3LYP/6-31+G (d, p) scheme proposed in this work. Nevertheless, they are expected to be slightly overestimated (about a factor of four).…”

Computational study on the mechanism and kinetics of NO3-initiated atmosphere oxidation of vinyl acetate

“…17 The US Environmental Protection Agency (US EPA) estimated that the total release of VAC in 2013 was about 619 tons. 18 While the atmospheric degradation of VAC has been studied experimentally [19][20][21][22][23][24] and computationally [25][26][27][28] with OH radicals and Cl atoms, only one experimental study 21 has investigated the oxidative reactions kinetics of VAC initiated by NO 3 in the presence of O 2 . In 2010, Picquet-Varrault et al investigated the gas-phase reaction of VAC with NO 3 using an evacuable environmental chamber with Fourier transform infrared and UV-visible spectrometers.…”