Gas-Phase Oxidation of Methyl Crotonate and Ethyl Crotonate. Kinetic Study of Their Reactions toward OH Radicals and Cl Atoms

2012 ◽  
Vol 116 (24) ◽  
pp. 6127-6133 ◽  
Author(s):  
Mariano A. Teruel ◽  
Julio Benitez-Villalba ◽  
Norma Caballero ◽  
María B. Blanco
Keyword(s):  
Kinetic Study ◽  
Gas Phase ◽  
Oh Radicals ◽  
Phase Oxidation ◽  
Gas Phase Oxidation ◽  
Cl Atoms

Study of the tropospheric degradation of 2-methylbutanal initiated by OH radicals, Cl atoms and sunlight

2021 ◽  
Author(s):  
María Asensio ◽  
Sergio Blázquez ◽  
María Antiñolo ◽  
José Albadalejo ◽  
Elena Jiménez
Keyword(s):  
Mass Spectrometry ◽  
Kinetic Study ◽  
Gas Phase ◽  
Oh Radicals ◽  
Phase Reaction ◽  
Gas Phase Reaction ◽  
Gas Phase Kinetics ◽  
Ftir Spectrometer ◽  
Kinetics Of ◽  
Cl Atoms

<p>The biogenic oxygenated volatile compound 2-methylbutanal (2MB) is emitted into the low atmosphere from several natural sources such as microbiological processes, wildland fires, or emissions from vegetation<sup>1</sup>. Moreover, some industrial operations also generate 2MB<sup>2</sup>. During the day, the oxidation of 2MB can be initiated by sunlight, hydroxyl (OH) radicals or chlorine (Cl) atoms in marine atmospheres. Up to date, gas-phase kinetics of OH with 2MB has only been studied at room temperature<sup>3</sup>. The photolysis rate coefficients (<em>J</em>) of 2MB initiated by sunlight have also been reported<sup>4</sup>. However, there is no available data for the reaction of Cl atoms with 2MB and the photolysis products.</p><p>In this work, the photolysis rate coefficient (<em>J</em>) of 2MB has been measured using a solar simulator in a Pyrex cell coupled to a Fourier Transform Infrared (FTIR) spectrometer to monitor the loss of 2MB. Moreover, the gas-phase kinetics of the reaction of 2MB with Cl (<em>k</em><sub>Cl</sub>) and OH (<em>k</em><sub>OH</sub>) have been investigated to evaluate the contribution of these homogeneous degradation routes to the total loss of 2MB in the atmosphere. All the kinetic experiments were carried out under free-NO<sub>x</sub> conditions (simulating a clean atmosphere). Regarding the relative kinetic study on the Cl-reaction, an atmospheric simulation chamber coupled to a FTIR spectrometer was used at 298 K and 760 Torr <sup>5</sup> of air, whereas for the absolute kinetics of the OH-reaction, <em>k</em><sub>OH</sub> was determined as a function of temperature and pressure (T = 263-353 K and P = 50-600 Torr of helium) by using a pulsed laser photolysis-laser induced fluorescence system<sup>6</sup>. Finally, in addition to FTIR, gas chromatography coupled to mass spectrometry and proton transfer time-of-flight mass spectrometry were used to detect the gas-phase reaction products when 2MB was exposed to Cl and sunlight. The atmospheric implications will be discussed in terms of lifetimes and reactions products.</p><p><strong>REFERENCES:</strong> <strong>1</strong>. Szwajkowska-Michale, L., Busko, M., Lakomy, P., and Perkowski, J.: Determination of profiles of volatile metabolites produced by Trametes versicolor isolates antagonistic towards Armillaria spp. Sylwan. <strong>2018</strong>, 162, 499–508. <strong>2. </strong>Kolar, P.; Kastner, J. R. Low-Temperature Catalytic Oxidation of Aldehyde Mixtures Using Wood Fly Ash: Kinetics, Mechanism, and Effect of Ozone. Chemosphere. <strong>2010</strong>, 78 (9), 1110–1115. <strong>3. </strong>D’Anna, B.; Andresen, O.; Gefen, Z. and Nielsen, C.J.: Kinetic study of OH and NO<sub>3</sub> radical reactions with 14 aliphatic aldehydes. Phys.Chem.Chem.Phys. <strong>2001</strong>, 3, 3057-3063. <strong>4. </strong>Wenger, J.C.: Chamber Studies on the Photolysis of Aldehydes. Environmental Simulation Chambers: Application to Atmospheric Chemical Processes. <strong>2006. </strong>Nato Science Series: IV: Earth and Environmental Science, vol 62. Springer, Dordrecht. <strong>5. </strong>Antiñolo, M.; Asensio, M.; Albadalejo, J. and Jiménez E.: Gas-Phase Reaction of trans-2-methyl-2-butenal with Cl: Kinetics, Gaseous Products, and SOA Formation. Atmosphere <strong>2020</strong>, 11 (7), 715. <strong>6. </strong>Blázquez, S.; Antiñolo, M.; Nielsen, O. J.; Albadalejo, J. and Jiménez, E.: Reaction kinetics of (CF<sub>3</sub>)<sub>2</sub>CFCN with OH radicals as a function of temperature (278-358 K): A good replacement for greenhouse SF<sub>6</sub>? Chem.Phys.Lett. <strong>2017</strong>, 687, 297-302.</p>

Gas Phase Oxidation of Nicotine by OH Radicals: Kinetics, Mechanisms, and Formation of HNCO

2016 ◽  
Vol 3 (9) ◽  
pp. 327-331 ◽  
Author(s):  
Nadine Borduas ◽  
Jennifer G. Murphy ◽  
Chen Wang ◽  
Gabriel da Silva ◽  
Jonathan P. D. Abbatt
Keyword(s):  
Gas Phase ◽  
Oh Radicals ◽  
Phase Oxidation ◽  
Gas Phase Oxidation

scholarly journals An isotope view on ionising radiation as a source of sulphuric acid

2012 ◽  
Vol 12 (2) ◽  
pp. 5039-5064 ◽  
Author(s):  
M. B. Enghoff ◽  
N. Bork ◽  
S. Hattori ◽  
C. Meusinger ◽  
M. Nakagawa ◽  
...  
Keyword(s):  
Gas Phase ◽  
Sulphuric Acid ◽  
Gamma Rays ◽  
Uv Light ◽  
Isotope Ratio Mass Spectrometry ◽  
Ionising Radiation ◽  
Oh Radicals ◽  
Phase Oxidation ◽  
Gas Phase Oxidation ◽  
Mass Dependent

Abstract. Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a missing source. In this study the production of sulphuric acid from SO2 through a number of different pathways is investigated. The production methods are standard gas phase oxidation by OH radicals produced by ozone photolysis with UV light, liquid phase oxidation by ozone, and gas phase oxidation initiated by gamma rays. The distributions of stable sulphur isotopes in the products and substrate were measured using isotope ratio mass spectrometry. All methods produced sulphate enriched in 34S and we find a δ34S value of 8.7 ± 0.4‰ (1 standard deviation) for the UV-initiated OH reaction. Only UV light (Hg emission at 253.65 nm) produced a clear non-mass-dependent excess of 33S. The pattern of isotopic enrichment produced by gamma rays is similar, but not equal, to that produced by aqueous oxidation of SO2 by ozone. This, combined with the relative yields of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV) to S(VI) conversion.

FTIR gas-phase kinetic study on the reactions of some acrylate esters with OH radicals and Cl atoms

2014 ◽  
Vol 21 (19) ◽  
pp. 11541-11551 ◽  
Author(s):  
A. Moreno ◽  
M. P. Gallego-Iniesta ◽  
R. Taccone ◽  
M. P. Martín ◽  
B. Cabañas ◽  
...  
Keyword(s):  
Kinetic Study ◽  
Gas Phase ◽  
Oh Radicals ◽  
Acrylate Esters ◽  
Cl Atoms

scholarly journals Why do organic aerosols exist? Understanding aerosol lifetimes using the two-dimensional volatility basis set

2013 ◽  
Vol 10 (3) ◽  
pp. 151 ◽  
Author(s):  
N. M. Donahue ◽  
W. Chuang ◽  
S. A. Epstein ◽  
J. H. Kroll ◽  
D. R. Worsnop ◽  
...  
Keyword(s):  
Human Health ◽  
Gas Phase ◽  
Fine Particles ◽  
Critical Role ◽  
Organic Aerosols ◽  
Basis Set ◽  
Oh Radicals ◽  
Phase Oxidation ◽  
Gas Phase Oxidation ◽  
Oxidation Chemistry

Environmental context Fine particles (aerosols) containing organic compounds are central players in two important environmental issues: aerosol-climate effects and human health effects (including mortality). Although organics constitute half or more of the total fine-particle mass, their chemistry is extremely complex; of critical importance is ongoing oxidation chemistry in both the gas phase and the particle phase. Here we present a method for representing that oxidation chemistry when the actual composition of the organics is not known and show that relatively slow oxidant uptake to particles plays a key role in the very existence of organic aerosols. Abstract Organic aerosols play a critical role in atmospheric chemistry, human health and climate. Their behaviour is complex. They consist of thousands of organic molecules in a rich, possibly highly viscous mixture that may or may not be in phase equilibrium with organic vapours. Because the aerosol is a mixture, compounds from all sources interact and thus influence each other. Finally, most ambient organic aerosols are highly oxidised, so the molecules are secondary products formed from primary emissions by oxidation chemistry and possibly non-oxidative association reactions in multiple phases, including gas-phase oxidation, aqueous oxidation, condensed (organic) phase reactions and heterogeneous interactions of all these phases. In spite of this complexity, we can make a strong existential statement about organic aerosol: They exist throughout the troposphere because heterogeneous oxidation by OH radicals is more than an order of magnitude slower than comparable gas-phase oxidation.

FTIR gas-phase kinetic study on the reactions of OH radicals and Cl atoms with unsaturated esters: Methyl-3,3-dimethyl acrylate, (E)-ethyl tiglate and methyl-3-butenoate

2013 ◽  
Vol 79 ◽  
pp. 546-552 ◽  
Author(s):  
Juan P. Colomer ◽  
María B. Blanco ◽  
Alicia B. Peñéñory ◽  
Ian Barnes ◽  
Peter Wiesen ◽  
...  
Keyword(s):  
Kinetic Study ◽  
Gas Phase ◽  
Oh Radicals ◽  
Unsaturated Esters ◽  
Cl Atoms

scholarly journals KINETIC STUDY OF SELECTIVE GAS-PHASE OXIDATION OF ISOPROPANOL TO ACETONE USING MONOCLINIC ZrO2AS A CATALYST

Química Nova ◽  
2015 ◽  
Author(s):  
Mohammad Sadiq ◽  
Muhammad Ali ◽  
Razia Aman ◽  
Haroon Ur Rashid ◽  
Muhammad Naveed Umar
Keyword(s):  
Kinetic Study ◽  
Gas Phase ◽  
Phase Oxidation ◽  
Gas Phase Oxidation
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