2597-43-5Relevant academic research and scientific papers
Addition of Water to Premixed Laminar Methanol-Air Flames: Experimental and Computational Results
Olsson, Jim O.,Karlsson, Lennart S.,Andersson, Lars L.
, p. 1458 - 1464 (1986)
Premixed laminar methanol-air flames at 100 torr were studied by experiment and computation.The composition CH3OH/O2/N2/Ar (12.3 percent /18.4 percent /65.3 percent /4.0 percent) corresponds to a stoichiometric composition.The effect of water addition was studied in stoichiometric flames containing about 2.3 mol percent water and 63 mol percent nitrogen but with methanol, oxygen, and argon concentrations unchanged.The amount of water added corresponded to 10 wt percent of the liquid phase.Species profiles were measured by using a modulated molecular beam mass spectrometer.They changed in an insignificant way when water was added.Detailed models for methanol-air combustion, including chemical kinetics and molecular diffusion, were used to compute the flame structure.The base mechanism used was a subunit of the mechanism developed by Westbrook, Dryer, and Schugh.Computations were also made with a mechanism developed by Warnatz.Water addition did not affect the computational concentration profiles significantly.Sensitivity analysis indicated the importance of HCO and CH2OH consumption reactions.Comparisons of experimental and computed concentration profiles supported a high value of the rate constant for the HCO decomposition reaction.This value, about a factor of 5 higher than the one used in the base mechanism, was in agreement with the value recommended by Warnatz.
Accessing the Nitromethane (CH3NO2) Potential Energy Surface in Methanol (CH3OH)-Nitrogen Monoxide (NO) Ices Exposed to Ionizing Radiation: An FTIR and PI-ReTOF-MS Investigation
Góbi, Sándor,Crandall, Parker B.,Maksyutenko, Pavlo,F?rstel, Marko,Kaiser, Ralf I.
, p. 2329 - 2343 (2018/03/21)
(D3-)Methanol-nitrogen monoxide (CH3OH/CD3OH-NO) ices were exposed to ionizing radiation to facilitate the eventual determination of the CH3NO2 potential energy surface (PES) in the condensed phase. R
High-temperature shock tube study of the reactions CH3 + OH → products and CH3OH + Ar → products
Vasudevan, Venkatesh,Cook, Robert D.,Hanson, Ronald K.,Bowman, Craig T.,Golden, David M.
, p. 488 - 495 (2008/12/21)
The reaction between methyl and hydroxyl radicals has been studied in reflected shock wave experiments using narrow-linewidth OH laser absorption. OH radicals were generated by the rapid thermal decomposition of tert-butyl hydroperoxide. Two different species were used as CH3 radical precursors, azomethane and methyl iodide. The overall rate coefficient of the CH3 + OH reaction was determined in the temperature range 1081-1426 K under conditions of chemical isolation. The experimental data are in good agreement with a recent theoretical study of the reaction. The decomposition of methanol to methyl and OH radicals was also investigated behind reflected shock waves. The current measurements are in good agreement with a recent experimental study and a master equation simulation.
The reactivity of ketyl and alkyl radicals in reactions with carbonyl compounds
Denisov
, p. 2110 - 2116 (2007/10/03)
A parabolic model of bimolecular radical reactions was used for analysis of the hydrogen transfer reactions of ketyl radicals: >C+OH + R1COR2 → >C=O + R1R2C+OH. The parameters describing the reactivity of the reagents were calculated from the experimental data. The parameters that characterize the reactions of ketyl and alkyl radicals as hydrogen donors with olefins and with carbonyl compounds were obtained: >C+OH + R1CH=CH2 → >C=O + R1C+ HCH3; >R1CH=CH2 + R2C+HCH2R3 → R2C+HCH3 + R2CH=CHR3. These parameters were used to calculate the activation energies of these transformations. The kinetic parameters of reactions of hydrogen abstraction by free radicals and molecules (aldehydes, ketones, and quinones) from the C-H and O-H bonds were compared.
Laboratory and theoretical study of the oxy radicals in the OH- and Cl-initiated oxidation of ethene
Orlando, John J.,Tyndall, Geoffrey S.,Bilde, Merete,Ferronato, Corinne,Wallington, Timothy J.,Vereecken, Luc,Peeters, Jozef
, p. 8116 - 8123 (2007/10/03)
The products of the OH-initiated oxidation mechanism of ethene have been studied as a function of temperature (between 250 and 325 K) in an environmental chamber, using Fourier transform infrared spectroscopy for end product analysis. The oxidation proceeds via formation of a peroxy radical, HOCH2CH2O2. Reaction of this peroxy radical with NO is exothermic and produces chemically activated HOCH2CH2O radicals, of which about 25% decompose to CH2OH and CH2O on a time scale that is rapid compared to collisions, independent of temperature. The remainder of the HOCH2CH2O radicals are thermalized and undergo competition between decomposition, HOCH2CH2O → CH2OH + CH2O (6), and reaction with O2, HOCH2CH2O + O2 → HOCH2-CHO + HO2 (7). The rate constant ratio, k6/k7, for the thermalized radicals was found to be (2.0 ± 0.2) × 1025 exp[-(4200 ± 600)/T] molecule cm-3 over the temperature range 250-325 K. With the assumption of an activation energy of 1-2 kcal mol-1 for reaction 7, the barrier to decomposition of the HOCH2CH2O radical is found to be 10-11 kcal mol-1. A study of the Cl-atom-initiated oxidation of ethene was also carried out; the main product observed under conditions relevant to the atmosphere was chloroacetaldehyde, ClCH2CHO Theoretical studies of the thermal and "prompt" decomposition of the oxy radicals were based on a recent ab initio characterization that highlighted the role of intramolecular H bonding in HOCH2CH2O. Thermal decomposition is described by transition state and the Troe theories. To quantify the prompt decomposition of chemically activated nascent oxy radicals, the energy partitioning in the initially formed radicals was described by separate statistical ensemble theory, and the fraction of activated radicals dissociating before collisional stabilization was obtained by master equation analysis using RRKM theory. The barrier to HOCH2CH2O decomposition is inferred independently as being 10-11 kcal mol-1, by matching both of the theoretical HOCH2CH2O decomposition rates at 298 K with the experimental results. The data are discussed in terms of the atmospheric fate of ethene.
An Investigation of the Methanol Decomposition Behind Incident Shock Waves
Dombrowsky, Ch.,Hoffmann, A.,Klatt, M.,Wagner, H. Gg.
, p. 1685 - 1687 (2007/10/02)
The pyrolysis of methanol was investigated behind incident shock waves at temperatures and densities between 1400 and 2200 K and 1*10-6 and 5*10-6 mol/cm3, respectively.Narrow band-width laser adsorption for OH radicals and ARAS technique for H atoms was used to determine the decomposition channels.For the experimental conditions described above the direct OH-formation is found to be the main channel of about 80percent of the decomposition rate.The channel leading to H and CH2OH is found to be less than 5percent.There remains the possibility of channels leading from methanol to 1CH2 + H2O or to CH2O + H2. Keywords: Chemical Kinetics / Methanol / Ring dye Laser / Shock Waves / Spectroscopy, Ultraviolet
Kinetic Studies of the Reactions of F and OH with CH3OH
McCaulley, J. A.,Kelly, N.,Golde, M. F.,Kaufman, F.
, p. 1014 - 1018 (2007/10/02)
By use of a discharge flow reactor apparatus with laser-excited fluorescence detection of OH and OD, rate coefficients were measured at 298 K and 3.0 Torr for seven isotopic variants of the OH + CH3OH reaction.The rate coefficients vary from (1.67 +/- 0.16) x 1E-13 cm3s-1 for OD + CD3OD to (1.01 +/- 0.10) x 1E-12 cm3s-1 for OH + CH3OH.The observed kinetic isotope effects were analyzed to obtain the CH3O yield, 0.15 +/- 0.08, of the OH + CH3OH reaction.Molecular-beam-sampled mass spectrometry was used to measure, at 298 K and P = 0.5-2.0 Torr, the relative yields of HF and DF from the reactions of F with CH3OD and CD3OH.The CH3O and CD3O yields of these reactions are 0.81 +/- 0.07 and 0.69 +/- 0.08, respectively.
Laboratory studies of the reactions of the nitrate radical with chloroform, methanol, hydrogen chloride and hydrogen bromide
Canosa-Mas, Carlos E.,Smith, Stuart J.,Toby, Sidney,Wayne, Richard P.
, p. 709 - 726 (2008/10/08)
Arrhenius parameters have been measured over the temperature range 298-523 K for the hydrogen abstraction reactions of NO3 with CH3OH, CHCl3 and HCl. A rate constant was determined at room temperature for the reaction of NO3 with HBr. Kinetic data were obtained by the discharge-flow technique operating at total pressures between 1.8 and 5.2 mmHg. The rate expression derived for the interactions with CH3OH, CHCl3 and HCl are 1.2 x 10-12 exp (-2560/T), 8.6 x 10-13 exp (-2815/T), and 4.0 x 10-12 exp (-3330/T) cm3 molecule-1 s-1. For the reaction of NO3 with HBr, the rate constant is 1.3 x 10-16 cm3 molecule-1 s-1 at 298 K. The hydrogen-abstraction reactions of NO3 are compared with those of O(3P) and OH.
REACTIONS OF FLUORINE ATOMS WITH NORMAL AND DEUTERATED METHANOLS.
Khatoon,Hoyermann
, p. 669 - 673 (2007/10/02)
The reactions of fluorine atoms with normal and deuterated methanols have been studied at low pressure using a fast discharge flow reactor. Samples were withdrawn continuously via a molecular beam sampling system and were analyzed by a mass-spectrometer. The rate constants have been determined.
Infrared Laser Techniques to Study the Structure and Dynamics of Transient Species
Woodin, R. L.,Kaldor, A.
, p. 269 - 276 (2007/10/02)
Infrared multiple photon laser induced chemistry has moved over the past ten years between the extremes of heralding truly intramolecular selective chemistry and being merely a laboratory curiosity.The maturing of infrared multiple photon excitation (IRMPE) now finds IRMPE used routinely in a variety of experiments including spectroscopy, chemical kinetics, thermodynamics and laser driven synthesis.Continuously tunable infrared laser sources now allow a much wider range of molecules to be excited, and the photophysics of IRMPE to be probed in greater detail, than was possible with only limited line tunability.Examples of both the pfotophysics of IRMPE and applications to kinetics and spectroscopy are discussed, including vibrational photodissociation spectra of isolated metal clusters.
