Gas-phase ozonolysis of ethene in the presence of hydroxylic compounds

Abstract

Ozonolysis of C2H4 was carried out at 295 K in 730 torr synthetic air in the concentration ranges of [O3]0 = 1.9–8.2 ppm and [C2H4]0 = 4.0–15.0 ppm, in the absence and presence of the added HCOOH (1 ppm), CH3COOH (1–10 ppm), and CH3OH (36–100 ppm). In the absence of the added compounds, a nearly complete analysis of the reaction products was achieved, with the yields expressed relative to the converted C2H4: HCHO 0.98, CO 0.26, CO2 0.18, HCOOH 0.05, and the sum of formic acid anhydride (FAN) and hydroperoxymethyl formate (HPMF), CHO(SINGLE BOND)O(SINGLE BOND)CH2OOH, 0.19. In the presence of the added HCOOH, the yield of [FAN + HPMF] increased. The addition of CH3COOH suppressed the formation of FAN and HPMF completely. The addition of large excesses of CH3OH also decreased the yield of [FAN + HPMF] significantly. In both cases, new products with the formula R(SINGLE BOND)O(SINGLE BOND)CH2OOH where R = CH3CO and CH3 for CH3COOH and CH3OH, respectively, were formed. The present results, together with the formation of hydroxymethyl hydroperoxide, HO(SINGLE BOND)CH2OOH, with added water vapor (Horie et al., Geophys. Res. Lett., 21, 1523, (1994)) were explained by the reaction of the Criegee biradical CH2OO with the added hydroxy compounds ROH. Formation of the products with the general formula R(SINGLE BOND)O(SINGLE BOND)CH2OOH indicates that the RO(SINGLE BOND)H bond fission has taken place. © 1996 John Wiley & Sons, Inc.

First-principles-derived kinetics of the reactions involved in low-temperature dimethyl ether oxidation

“…Experimental highpressure limit rates are unknown for these reactions. Conditions for known experiments are around the standard conditions of 298 K and 1 atm [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. Considerations at higher temperatures and pressures have never been made for these reactions, but will be considered here in the low-temperature combustion of dimethyl ether.…”

“…This is consistent with the ÁH z 298 ¼ 69:6 kcal mol À1 ((CCSD(T)/6-311þG(3df, 3pd)) result calculated by Cremer et al [15] (from the lowest energy configuration of formic acid). A summary of all reaction rate constants is given in Table 4 [40][41][42], HC(¼O)OH [40,49,52,54,82], SO 2 [40,83], NO [84], NO 2 [84], CO [40], and CO 2 [40]. Theoretical calculations on a subset of these possible bimolecular reactions (CH 2 OO with H 2 O, H 2 C¼O, HC(¼O)OH, SO 2 , and CO 2 ) have been done only recently.…”

Reactivity of stabilized Criegee intermediates (sCIs) from isoprene and monoterpene ozonolysis toward SO<sub>2</sub> and organic acids

“…Fenske et al, 2000). Reaction of CH 2 OO with formic acid, HCOOH, yielding to production of hydroperoxymethyl formate was demonstrated by Neeb et al (1995Neeb et al ( , 1996, with follow-up studies by Thamm et al (1996) and Hasson et al (2001b). Neeb et al (1997) showed that the rate coefficient for the above reaction is relatively large (14 000-fold) in comparison to the reaction rate coefficient for CH 2 OO + water.…”

“…Due to the relatively long lifetime of sCI, bimolecular reactions of sCIs with several compounds like water vapour, SO 2 , carbonyls, organic acids, etc., are also possible (e.g. Neeb et al, 1996Neeb et al, , 1997Johnson, 2001;Welz et al, 2012Welz et al, , 2014Mauldin III et al, 2012;Berndt et al, 2012Berndt et al, , 2014aTaatjes et al, 2012Taatjes et al, , 2013. These reactions can potentially be fast enough to contribute significantly to the atmospheric oxidation capacity.…”

Review of Recent Smog Chamber Studies for Secondary Organic Aerosol

“…ROO·와 HO 2 반응으로 organic hydroperoxide wacki et al, 2012;Atkinson and Arey, 2003;Benson, 1965). Alkoxy radical (RO·) 역시 peroxy radical (ROO·) Taatjes et al, 2013;Mauldin Iii et al, 2012;Welz et al, 2012;Neeb et al, 1996;Hatakeyama and Akimoto, 1994;Lai et al, 1990). 두 번째 경로는 peroxide channel (그림 3)인데, isomerization으로 δ 위치에 있는 탄소에 결합해 있는 수소원자 를 빼앗아서 (또는 1,4 hydride shift) organic hydroper-…”