Reaction Kinetics of Catechol (1,2-Benzenediol) and Guaiacol (2-Methoxyphenol) with Ozone

Abstract

The kinetic reactions of 1,2-benzenediol (catechol) and 2-methoxyphenol (guaiacol) with ozone were studied in a simulation chamber (8 m(3)) under dark conditions. The rate coefficients were measured at 294 ± 2 K, atmospheric pressure and dry conditions (relative humidity, RH < 1%), except for 1,2-benzenediol where they were also measured as a function of relative humidity (RH = 1-80%). The concentrations of organic compounds were followed by a PTR-ToF-MS for a continuous monitoring of gas-phase species. The O3 rate coefficients were obtained using both the pseudo-first-order and relative rate methods. The values (in cm(3) molecule(-1) s(-1)) determined for catechol and guaiacol under dry conditions are (13.5 ± 1.1) × 10(-18) and (0.40 ± 0.31) × 10(-18), respectively. The rate coefficient of catechol was found to be independent of RH below 20% and above 60%, whereas for RH between 20% and 60% it decreases with increasing RH. The determined rate coefficients have been used to evaluate the atmospheric lifetime of each compound with respect to O3. To our knowledge, this study represents the first determination of the ozone rate coefficient with guaiacol and is also the first kinetic investigation for the influence of the relative humidity on the oxygenated aromatic ozonolysis.

Rate constant and secondary organic aerosol formation from the gas-phase reaction of eugenol with hydroxyl radicals

“…Methoxyphenols are semivolatile aromatic compounds with low molecular weight, and many of them are found to mainly exist in the gas phase at typical ambient temperature (Schauer et al, 2001;Simpson et al, 2005). Thus, methoxyphenols can be chemically transformed through gas-phase reactions with atmospheric oxidants (Coeur-Tourneur et al, 2010a;Lauraguais et al, 2012Lauraguais et al, , 2014aLauraguais et al, , b, 2015Lauraguais et al, , 2016Yang et al, 2016;Zhang et al, 2016;El Zein et al, 2015). The corresponding rate constants control their effectiveness as stable tracers for wood combustion and atmospheric lifetimes.…”

“…The corresponding rate constants control their effectiveness as stable tracers for wood combustion and atmospheric lifetimes. In recent years, the rate constants for the gas-phase reactions of some methoxyphenols with hydroxyl (OH) radicals (Coeur-Tourneur et al, 2010a;Lauraguais et al, 2012Lauraguais et al, , 2014bLauraguais et al, , 2015, nitrate (NO 3 ) radicals (Lauraguais et al, 2016;Yang et al, 2016;, chlorine atoms (Cl) (Lauraguais et al, 2014a), and ozone (O 3 ) (El Zein et al, 2015) have been determined. Some studies have indicated significant SOA formation from 2,6-dimethoxyphenol (syringol) and 2-methoxyphenol (guaiacol) with respect to their reactions with OH radicals (Sun et al, 2010;Lauraguais et al, 2012Lauraguais et al, , 2014bAhmad et al, 2017;Yee et al, 2013;Ofner et al, 2011).…”

Supplementary material to &quot;Photooxidants from Brown Carbon and Other Chromophores in Illuminated Particle Extracts&quot;

“…1 Syringol 9.6E-11 (Lauraguais et al, 2012) 4.0E-19 b (Zein et al, 2015) 2.6E+10 (O'Neill and Steenken, 1977) 3.6E+07 (Tratnyek and Hoigne, 1991a) 1.3E+04 c (Hoigné and Bader, 1983) 3.7E+09 (Kaur and Anastasio, 2018), (Smith et al, 2015) 2…”

Enhancement of Secondary Organic Aerosol Formation and its Oxidation State by SO&lt;sub&gt;2&lt;/sub&gt; during Photooxidation of 2-Methoxyphenol

“…Its emission factor of wood burning is in the range of 172−279 mg kg -1 fuel (Schauer et al, 2001). In recent years, the reactivity of gas-phase guaiacol toward OH radicals (Coeur-Tourneur et al, 2010a), NO3 radicals (Lauraguais et al, 2016;Yang et al, 2016), chlorine atom (Lauraguais et al, 2014a), and O3 (El Zein et al, 2015) has been investigated, suggesting that its degradation by OH radicals and NO3 radicals might be predominant Atmos. Chem.…”