Removal by H

Subscriber access provided by University of Massachusetts Amherst Libraries

A: Kinetics, Dynamics, Photochemistry, and Excited States 2

1

g+

2

2

4

2

4

O(b# ) Removal by H, CO, NO, CH and CH in the 300–800 K Temperature Range Marsel Vakifovich Zagidullin, Nikolay Anatol'evich Khvatov, Georgiy I Tolstov, Iakov A. Medvedkov, Alexander Moiseevich Mebel, Michael Charles Heaven, and Valeriy N. Azyazov J. Phys. Chem. A, Just Accepted Manuscript • DOI: 10.1021/acs.jpca.8b03122 • Publication Date (Web): 30 May 2018 Downloaded from http://pubs.acs.org on May 30, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

The Journal of Physical Chemistry

1

O2(b1 ) Removal by H2, CO, N2O, CH4 and C2H4 in the 300–800 K Temperature Range M. V. Zagidullin1,2, N.A. Khvatov1,2, G. I. Tolstov1, I. A. Medvedkov1, A. M. Mebel*,1,3, M. C. Heaven1,4, and V. N. Azyazov*,1,2 1 2 3

Samara University, Samara 443086, Russia

Lebedev Physical Institute of RAS, Samara 443011, Russia

Florida International University, Miami, Florida 33199, USA 4

Emory University, Atlanta, Georgia 30322, USA

Abstract. Rate constants for the removal of O2 b1 Σ by collisions with species relevant to

combustion, H2, CO, N2O, CH4 and C2H4 have been measured in the temperature range of 297– 800 K. O2(b1Σ ) was produced from ground-state molecular oxygen by photoexcitation pulses from a tunable dye laser and the deactivation kinetics were followed by observing the temporal

behavior of the b1Σ – X3Σ fluorescence. The removal rate constants for H2, CO, N2O, CH4, and

C2H4

could

be

kH2=(1.44±0.02)×10-16T1.5

represented

kN2O=(2.63±0.14)×10-18T1.5

kC2H4=(2.34±0.10)×10–20T2.5exp

0 ± 10 T

,

590 ± 26 T

by

the

modified

Arrhenius

,

kCO=(6.9±0.4)×10–24T3

kCH4=(3.5±0.2)×10–18T1.5

expressions

939 ± 33 T

,

and

–(220 ± 24) T

cm3 molecule–1 s–1, respectively. All of the rate

680 ± 16 T

constants measured at room temperature were found to be in good agreement with previously reported values, whereas the values at elevated temperatures up to 800 K were systematically measured for the first time.

ACS Paragon Plus Environment

The Journal of Physical Chemistry 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

2 1.

Introduction

Gas phase processes involving oxygen molecules in the electronically excited state b1Σ

have been studied extensively due to their importance in the terrestrial atmosphere,1–3 oxygen– containing gas discharges,4–6 the active medium of an oxygen–iodine laser,7,8 and combustion9– 12

. Currently, a nonequilibrium plasma discharge has been actively studied13–18 in view of its

potential applications to ignition and flame stabilization. An important point is that plasma– chemical processes result in the formation of highly reactive atoms, radicals, and excited molecules including O2.10,13,19,20 In particular, plasma–chemical processes in air–fuel mixtures result in the formation of O2(b1 Σ ) molecules that may activate chain reactions in the

combustion zone.20 Analysis of the reaction kinetics involving O2(b1Σ ) is difficult due to the

fact that there is little published data concerning the deactivation kinetics at temperatures above 350 K.

Studies of O2(b1Σ ) deactivation at room temperature by molecules relevant to combustion

including H2,21–31 CH4,21,22,25,28,32,33 CO,21,23,33 N2O,21,22,34–36 and C2H4,22 have been reported in many works, a partial list of which is given in Table 1. The gas temperature in many oxygen– containing mixtures can be much higher than ambient when reactions are in progress, which

makes it important to study the kinetics of processes with the O2(b1Σ ) molecule at elevated temperatures. Temperature-dependent rate constants for the removal of O2(b1 Σ ) have been

measured with the following colliders: Н2,26–30 CH4,28 and N2O.35,36 Only in a few of these

papers were fitting equations for the temperature-dependent rate constants presented. To our knowledge, no studies of quenching of O2(b1Σ ) by CO and C2H4 at high temperatures have

been reported in the literature. Recently,37 we measured the temperature dependence of rate constants for the removal of O2(b1Σ ) by collisions with M = CO2, N2, H2O, and O2 for the

temperature range of 297−800 K. The present work continues these studies with the aim to

determine rate constants for the removal of O2(b1Σ ) by the combustion-relevant species H2,

CH4, CO, N2O, and C2H4 at temperatures up to ~800 K using time–resolved emission from the O2 b1Σ – X3Σ transition.

2. Experiment The measurements were carried out by observing the decay profiles of emission intensity

from excited oxygen O2(b1Σ ) on the addition of the quencher to the oxygen flow, using a pulsed

dye laser to excite the b1 Σ state. The apparatus, earlier used to measure the temperature

dependence of O2(b1 Σ ) quenching by N2, CO2, H2O, O2 has been described in detail ACS Paragon Plus Environment

Page 2 of 20

Page 3 of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


3 previously.37 A flowing mixture of oxygen + quencher gas mixture was pumped through a fluorescence cell (FC). The cell consisted of a cylindrical quartz tube 40 cm long, with an internal diameter of 15 mm, with the ends sealed by quartz windows. The oxygen and quencher gas flows were mixed right before the entrance to the FC. Heating of the walls of the quartz tube was used to increase the gas temperature. This was maintained by resistive heating via nichrome tape wound around the outside of the quartz tube. A layer of thermal insulation was applied over the nicrome tape to reduce heat loss and facilitate temperature stabilization. To observe emission from O2(b1Σ ), a 2 cm long and 1 cm high rectangular window was located in the center of FC.

This aperture was free of insulating materials and heating tape. The gases used in the experiments had the following minimum purities as stated by the manufacturers: O2 (>99.99995), СO–Ar (Linde, CO=(10.11±0.15)%, Ar=89.89%, H2O99.8%, H2O99.9%). The H2 flow (99.999%) was produced by a hydrogen generator (Metachrom GV–VH–16). The gas temperature in the laser induced fluorescence (LIF) region was measured by a thermocouple. The beam from a dye laser (Sirah Precision Scan, PSCAN–D–18–EG, wavelength near 690 nm, pulse energy 0.15 J, beam diameter 6 mm, pulse duration 10 ns, repetition rate 10 Hz, spectral emission width 0.03 cm−1) was directed along the central axis of the FC. This laser pulse

excited transitions to the (b1Σ , υ=1) state. In an excess of O2(X), the O2(b1Σ , υ=1) state was

rapidly relaxed to O2(b1 Σ , υ=0) by efficient E−E and V−V energy–exchange processes.38

Oxygen 1 Σ , υ=0 → 3 Σ , υ=0 emission was observed through FC window, along the axis

perpendicular to the dye laser beam. The light was collected and focused on the entrance slit of a

monochromator (MDR–206), that transmitted wavelengths in the 762 ± 8 nm range. Additional long–pass filters were used to reduce the scattered radiation at 690 nm. Time–resolved LIF signals were recorded using a PMT (Hamamatsu R636–10). To measure time resolved fluorescence decay curves, the PMT output signals were collected in a digital oscilloscope (LeCroy Wavesurfer–3054R).

3. Results The experiments with colliders of interest were performed under the conditions presented in Table 2. The PMT temporal profiles shown in Figure 1 exhibit bi–exponential behavior due to the instrumental decay caused by short duration (10 ns) laser scattering and the decay of 1Σ → Σ emission. The decay of these profiles can be fitted using a sum of exponentials of the form

3

+ exp (− ) + (−) , where (1/Kr) is the instrumental electronics response time

on the order of 2µs. The decay rate of O2(b1Σ ) removal (K) via the processes ACS Paragon Plus Environment


Page 4 of 20

4 O2(b1Σ ) + O2 → 2O2

is given by the expression

where

O2(b1Σ ) + M → O2 + M.

(2)

=

(3)

+ !

= "1 +

Here

(1)

!,

$

%$

&.

and ! are the number densities of oxygen O2 and an admixed gas M,

$

is the

number density of water vapor impurity in the oxygen flow, and ! are rate constants of

processes (1) and (2), respectively, $ is rate constant of O2(b1Σ ) removal by H2O. Note that the radiative decay of O2(b1Σ ) is negligibly slow for the time scale of these measurements. Application of the ideal gas approximation yields the expression37

( =

where

)* + ,

( = +

-

-

-0

-./

./

,

! .

(4)

is the combined rate coefficient. Here, P is the gas pressure, Т is the gas temperature, kB is the Boltzmann constant, G is the total flow rate, GM is the flow rate of the admixed gas M. In the case of the O2/Ar/CO mixture, GM is the total flow rate of the Ar/CO mixture,

( = (1 1 + 23 (1 − 1 )), and 1 is the molar fraction of CO in the Ar/CO mixture. The

plot of km versus GM/GO2 for the flowing gas is analogues to the Stern–Volmer plot of K versus the number density of M for static condition. The slope of the linear fit according to equation (4) gives rate constant kM. The set of data of kM vs T was then fitted to a modified Arrhenius expression kM(T)=A×T0.5n exp(–E/T)

(5)

where the best fits for analytical temperature dependence of the rate constants were obtained with integer values of n. It was observed that the temperature of the gas mixture in the LIF observation region directly opposite the center of the fluorescence observation window was somewhat lower than the upstream or downstream temperatures. For example, at a nominal temperature of 800 K, the ACS Paragon Plus Environment

Page 5 of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


5 temperature near the center of the window was 20 K lower than 1 cm upstream and downstream. At lower temperatures, the difference was smaller. The temperature gradient was present because the higher heat transfer through the window in the wall of the quartz tube. The temperature variations were taken into account in estimating the measurement errors. The rate constants km as a function of GH2/GO2 are shown in Figure 2 for the O2/H2 mixture at three selected temperatures. In all experiments performed, the decay rate K was lower than 50000 s–1. Linear fitting gave values for rate constants of (7.3±0.2)×10–13 cm3/s, (1.89±0.04)×10-12 cm3/s, and (3.18±0.1)×10–12 cm3/s for 297, 570,and 780 K, respectively. The error limits in the rate coefficients were derived from the uncertainty in the flow rates, pressure, and temperature. They also include the standard errors in the fitting of the PMT response temporal profile and the uncertainty in the slope obtained in the linear least–square fit of km. As

follows from Eq. (4), ( = at GH2/GO2 = 0. As can be seen from Fig. 2, > . For

example at T = 780 K, =1.16×10-15 cm3/s, whereas = 5.0×10-16 cm3/s, which was

measured in our recent paper37 with the actions taken to reduce the H2O content using a water vapor trap held at -100°C. In the present work, we have not taken additional measures to remove water vapor and therefore > .

The symbols in Figure 3 show the measured values of the rate constant kH2 against the gas

temperature. The solid curve in this Figure represents a nonlinear least–square fit of kH2(T) as a function of temperature in the range of 297–780 K. The room temperature rate constant value and the expression for kH2(T) are given in Table 1. In a number of papers,26–30 the fitted temperature dependences for kH2(T) were also presented in a relatively narrow temperature range. The expressions for kH2(T) reported early26-29 are presented in Table 1, whereas the plots of these functions extrapolated up to the temperature of 800 K are shown in Figure 3. As can be seen, the discrepancies between values of kH2(T) reported by different authors do not exceed 25 % in the temperature range of interest. The experimental results obtained by Kozlov et al.30 for temperatures up to 800 K are well described by the temperature dependence proposed in Ref. 28. Similar measurements of the rate constants were carried out with the other collisional partners CH4, CO, N2O, and C2H4. The results of measurements (symbols) and plots of expressions for kM(T) (solid curves) for these removal agents are shown in Figures 4–7. The room temperature rate constants and expressions for kM(T) are presented in Table 1. In the case of the CO/Ar mixture the fact39 that kCO>>kAr was used for evaluating kCO. The available alternative expressions for kM(T) reported for CH4 and N2O for temperatures < 400 K are presented in Table 1. The plots of these functions (dashed curves), extrapolated up to the temperature of 800 K, are shown in Figures 4 and 6. For these two species, the dependences of



6 kM(T) presented here and proposed by other authors28,36 differ insignificantly for temperatures below 400 K but diverge with increasing T. Borrell et al.28,40 have also reported the dependence of kN2O in the temperature interval of 300−1400 K. They found that the rate constant increases with temperature up to ∼800 K and then becomes temperature independent. The value of the rate constant at 800 K is approximately 1.25 higher than at 300 K, which is also observed in our experiment (see Fig. 6). Borrell et al.40 have measured rate constants at about 300 K and 600 K but not between these temperatures and therefore they could not see the minimum at about 400 K observed by us. The temperature range of 800-1400 K where Borrell et al. found no temperature dependence is outside of our measurements.

4.

Discussion As the M + O2 gas mixture flows through the FC, stable oxidation products can be

formed, that can change the decay rate of the O2(b1Σ ) number density.41 It was noted earlier30

that in a mixture of H2/O2 staying a few minutes at temperatures above 600 K some amount of water forms leading to a systematic error in the measured rate of the O2(b1 Σ ) decay.

Nevertheless, in our work for the entire range of experimental conditions, the dependence of km on the ratio GM/GO2 was monotonous and linear, like the one shown in Figure 2. Indirectly, this indicates that the production of other quencher molecules in dark reactions during a few seconds of residence time in our experiments is negligible. The measured values of the rate constants at room temperature appeared to be in good agreement with the results of previous studies. For each of the collisional partners M a fitting expression of the type (5) was derived in the temperature range of 297–800 K. For comparison, Table 1 shows the available expressions for the temperature dependence of kH2, kCH4, and kN2O at T < 400 K reported previously.26–31,36 These expressions give approximately the same values of the rate constants as in present work at low temperatures (Figures 3, 4, and 6). At higher temperatures, one can observe a discrepancy between our measurements and predictions using these expressions, clearly showing that experimental measurements of these rate constants are necessary to improve the quality of the predictions. Figure 6 shows that the rate constant kN2O decreases with temperature up to T = 400 K and then starts rising again. Figures 4 and 6 in our previous work37 exhibit similar temperature

dependences for the rate constants of O2(b1Σ ) removal by CO2 and H2O, respectively. In that ACS Paragon Plus Environment

Page 6 of 20

Page 7 of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


7 work, we discussed possible relation of such behavior to the energy of a conical intersection,

through which the system funnels during the quenching process, relative to the O2(b1Σ ) + M

asymptote. For instance, if the conical intersection lies below the asymptote, the quenching reaction could be expected to behave similarly to a barrierless chemical reaction occurring without activation energy and hence, the rate constant would exhibit a slightly negative temperature dependence converting into a slightly positive temperature dependence at higher temperatures. In turn, a relatively low energy of the conical intersection could be associated with attractive interaction between O2(b1Σ ) and the collision partner resulting in the formation of a O2(b1Σ )…M complex. 5.

Conclusion

Rate constants for the collisional removal of O2 b1 Σ are important for better

understanding of various processes in the terrestrial atmosphere, oxygen–containing gas discharges, the active medium of an oxygen–iodine laser, and plasma-assisted combustion involving electronically excited molecular oxygen. Rate constants have been measured for the

collision partners H2, CO, N2O, CH4, and C2H4 in the temperature range of 297–800 K. To

perform these measurement, O2(b1Σ ) was produced from ground-state molecular oxygen by

photoexcitation using a pulsed tunable dye laser and the deactivation kinetics were followed through the observation of the temporal decay of the b1Σ – X3Σ fluorescence. Fitting of the

measured removal rate constants for H2, CO, N2O, CH4, and C2H4 using modified Arrhenius expressions

gave

the

kCO=(6.9±0.4)×10–24T3

following

kCH4=(3.5±0.2)×10–18T1.5

results:

939 ± 33 T

,

kH2=(1.44±0.02)×10-16T1.5

kN2O=(2.63±0.14)×10-18T1.5

and kC2H4=(2.34±0.10)×10–20T2.5exp

0 ± 10 T

590 ± 26 T

, ,

cm3

–(220 ± 24)

680 ± 16

T

T

molecule–1 s–1. The rate constants measured at room temperature were found to be in good agreement with the available literature values, whereas the values at elevated temperatures up to 800 K were systematically measured for the first time. The measured values of the rate constants and fitting expressions for kM(T) can be used in modeling of the gas kinetics processes involving

O2(b1Σ ) molecules in the temperature range 297–800 K. 6.

Acknowledgments

This work was supported by the Ministry of Education and Science of the Russian Federation under the Grant No. 14.Y26.31.0020 to Samara University.



8 References (1)Slanger, T. G.; Copeland, R. A. Energetic Oxygen in the Upper Atmosphere and the Laboratory. Chem. Rev. 2003, 103, 4731–4766. (2)Kirillov, A. S. The Calculations of Quenching Rate Coefficients of O2(b1Σ ) in Collisions with O2, N2, CO, CO2 Molecules. Chem. Phys. 2013, 410, 103–108. (3)Krasnopolsky, V. A. Excitation of the Oxygen Nightglow on the Terrestrial Planets. Planet. Space Sci. 2011, 59, 754–766. (4)Nayak, G.; Sousa, J. S.; Bruggeman, P. J. Singlet Delta Oxygen Production in a 2D Micro– Discharge Array in air: Effect of Gas Residence Time and Discharge Power. J. Phys. D: Appl. Phys. 2017, 50, 105205. (5)Wegner, T.; Küllig, C.; Meichsner, J. On the EH Transition in Inductively Coupled Radio Frequency Oxygen Plasmas: I. Density and Temperature of Electrons, Ground State and Singlet Metastable Molecular Oxygen. Plasma Sources Sci. Technol. 2017, 26, 025006. (6)Mankelevich, Y. A.; Voronina, E. N.; Poroykov, A. Y.; Rakhimova, T. V.; Voloshin, D. G.; Chukalovsky, A. A. Plasmachemical and Heterogeneous Processes in Ozonizers with Oxygen Activation by a Dielectric Barrier Discharge. Plasma Phys. Rep. 2016, 42, 956–969. (7)Zagidullin, M. V.; Khvatov, N. A.; Malyshev, M. S.; Azyazov, V. N. Dissociation of Iodine Molecules and Singlet Oxygen Generation in O2–I2 Mixture Induced by 1315–nm Laser Radiation. Quantum Electron. 2017, 47, 932-934. (8)Pichugin, S. Yu.; Heaven, M. C. A Pared–Down Gas–Phase Kinetics for the Chemical Oxygen–Iodine Laser Medium. Chem. Phys. 2013, 425, 80–90. (9)Starik, A. M.; Pelevkin, A. V.; Titova, N. S. Modeling Study of the Acceleration of Ignition in Ethane–Air and Natural Gas–Air Mixtures via Photochemical Excitation of Oxygen Molecules. Combust. Flame 2017, 176, 81–93. (10) Konnov, A. A. On the Role of Excited Species in Hydrogen Combustion. Combust. Flame 2015, 162, 3755–3772. (11) Bezgin, L. V.; Kopchenov, V. I.; Starik, A. M.; Titova, N. S. Numerical Analysis of Combustion of a Hydrogen–Air Mixture in an Advanced Ramjet Combustor Model During Activation of O2 Molecules by Resonant Laser Radiation. Combust. Explos. Shock Waves 2017, 53, 249–261. (12) Pelevkin, A. V.; Loukhovitski, B. I.; Sharipov, A. S. Reaction of H2 with O2 in Excited Electronic States: Reaction Pathways and Rate Constants. J. Phys. Chem. A 2017, 121, 9599– 9611. (13) Popov, N. A. Kinetics of Plasma–Assisted Combustion: Effect of Non–Equilibrium Excitation on the Ignition and Oxidation of Combustible Mixtures. Plasma Sources Sci. Technol. 2016, 25, 043002. (14) Lin, B. X.; Wu, Y.; Zhang, Z. B.; & Chen, Z. Multi–Channel Nanosecond Discharge Plasma Ignition of Premixed Propane/Air under Normal and Sub–Atmospheric Pressures. Combust. Flame 2017, 182, 102–113. (15) Winters, C.; Eckert, Z.; Yin, Z.; Frederickson, K.; Adamovich, I. V. Measurements and Kinetic Modeling of Atomic Species in Fuel–Oxidizer Mixtures Excited by a Repetitive Nanosecond Pulse Discharge. J. Phys. D: Appl. Phys. 2017, 51, 015202.


Page 8 of 20

Page 9 of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


9 (16) Rousso, A.; Yang, S.; Lefkowitz, J.; Sun, W.; Ju, Y. Low Temperature Oxidation and Pyrolysis of n–Heptane in Nanosecond–Pulsed Plasma Discharges. Proc. Combust. Inst. 2017, 36, 4105–4112. (17) Shcherbanev, S. A.; Popov, N. A.; Starikovskaia, S. M. Ignition of High Pressure Lean H2: Air Mixtures along the Multiple Channels of Nanosecond Surface Discharge. Combust. Flame 2017, 176, 272–284. (18) Retter, J. E.; Elliott, G. S.; Kearney, S. P. Dielectric–Barrier–Discharge Plasma–Assisted Hydrogen Diffusion Flame. Part 1: Temperature, Oxygen, and Fuel Measurements by One– Dimensional fs/ps Rotational CARS Imaging. Combust. Flame 2018, 191, 527-540. (19) Ombrello, T.; Won, S. H.; Ju, Y.; Williams, S. Flame Propagation Enhancement by Plasma Excitation of Oxygen. Part II: Effects of O2(a1∆g). Combust. Flame 2010, 157, 1916–1928. (20) Starik, A.; Sharipov, A. Theoretical Analysis of Reaction Kinetics with Singlet Oxygen Molecules. Phys. Chem. Chem. Phys. 2011, 13, 16424–16436. (21) Filseth S.V.; Zia A.; Welge K. H. Flush Photolyc Production, Reactive Lifetime and Collisional Quenching of O2(b1Σ, υ =0). J. Chem. Phys. 1970, 52, 5502–5510. (22) Becker K. H.; Groth W.; Schurath U. The Quenching of Metastable O2(a1∆g) and O2(b1Σ ) Molecules Chem. Phys. Lett. 1971, 8, 259–262. (23) Choo, K. Y.; Leu, M. T. Rate Constants for the Quenching of Metastable O2(b1 Σ ) Molecules. Int. J. Chem. Kinet. 1985, 17, 1159–1167. (24) Singh J. P.; Setser D. W. Electronic–to–Vibrational Energy–Transfer Studies of Singlet Molecular Oxygen O2(b1Σ ). J. Phys. Chem. 1985, 89, 5353–5358. (25) Wildt, J.; Bednarek, G.; Fink, E. H.; Wayne R. P. Laser Excitation of O2(b1Σ , υ= 0, 1, 2) – Rates and Channels of Energy Transfer and Quenching. Chem. Phys. 1988, 122, 463–470. (26) Hohmann, J.; Müller, G.; Schönnenbeck, G.; Stuhl, F. Temperature–Dependent Quenching of O2(b1Σ ) by H2, D2, CO2, HN3, DN3, HNCO and DNCO. Chem. Phys. Lett. 1994, 217, 577–581. (27) Talukdar, R. K.; Dunlea, E. J.; Brown, S. S.; Daniel, J. S.; Ravishankara, A. R. Kinetics of O2(b1Σ) Reaction with H2 and an Upper Limit for OH Production. J. Phys. Chem. A 2002, 106, 8461–8470. (28) Kohse–Höinghaus, K.; Stuhl, F. H2 Laser Photochemical Study of the Temperature Dependent Quenching of O2(b1Σg+). J. Chem. Phys. 1980, 72, 3720–3726. (29) Braithwaite, M.; Ogryzlo, E. A.; Davidson, J. A.; Schiff H. I. O2(b1 Σ ) Relaxation in Collisions. Part 2.–Temperature Dependence of the Relaxation by Hydrogen. J. Chem. Soc., Faraday Trans. 2 1976, 72, 2075-2081. (30) Kozlov, D. N.; Kobtsev, V. D.; Stel’makh, O. M.; Smirnova, V. V. Study of Collisional Deactivation of O2(b) Molecules in a Hydrogen–Oxygen Mixture at High Temperatures Using Laser–Induced Gratings. J. Exp. Theor. Phys. 2013, 117, 36–47. (31) Borrell, P.; Richards, D. S. Quenching of Singlet Molecular Oxygen, O2(a1 ∆ ) and O2(b1Σ) by H2, D2, HCl and HBr. J. Chem. SOC., Faraday Trans. 2 1989, 85, 1401–1411. (32) Davidson, J. A.; Ogryzlo, E. A. The Quenching of O2(1Σ ) by Aliphatic Hydrocarbons. Can. J. Chem. 1970, 52, 240–245. (33) Dunlea, E. J.; Talukdar, R. K.; Ravishankara, A. R. Kinetic studies of Reactions of O2(b1 ) with Several Atmospheric Molecules. J. Phys. Chem. A 2005, 109, 3912-3920.



10 (34) Boodaghians, R.; Borrell, P.; Borrell, P. Room–Temperature Rate Constants for the Gas– Phase Quenching of Metastable Molecular Oxygen O2(a1∆g) and O2(b1Σ ) by CO2, N2O, NO, NH, HCI and SO2. Chem. Phys. Lett. 1983, 97, 193–197. (35) Borrell, P. M.; Borrell, P.; Grant, K. R. Inverse Temperature Dependencies in the Quenching of Singlet Oxygen O2(b1Σ ) by CO2 and N2O Studied with a Discharge Flow/Shock Tube. J. Chem. Phys. 1983, 78, 748–756. (36) Dunlea, E. J.; Talukdar, R. K.; Ravishankara, A. R. Kinetics and Products of the Reaction O2(b1Σ ) with N2O. Z. Phys. Chem. 2010, 224, 989–1007. (37) Zagidullin, M.V.; Khvatov, N. A.; Medvedkov, I. A.; Tolstov, G. I.; Mebel, A. M.; Heaven, M. C.; Azyazov, V. N. O2(b1Σg+) Quenching by O2, CO2, H2O, and N2 at Temperatures of 300–800 K. J. Phys. Chem. A 2017, 121, 7343–7348. (38) Bloemink, H. I.; Copeland, R. A.; Slanger, T. G. Collisional Removal of O2(b1Σ , υ=1, 2) by O2, N2, and CO2. J. Chem. Phys. 1998, 109, 4237–4245. (39) Kebabian, P. L.; Freedman, A. Rare Gas Quenching of Metastable O2(b1Σ ) at 295 K. J. Phys. Chem. A 1997, 101, 7765–7767. (40) Borrell, P. M.; Borrell, P.; Richards, D. S.; Quinney, D. The Quenching of O2(b1Σg+) at High Temperatures. J. Chem. Faraday Trans. 2 1987, 83, 2045-2052. (41) Tsang, W.; Hampson, R. F. Chemical Kinetic Data Base for Combustion Chemistry. Part I. Methane and Related Compounds. J. Phys. Chem. Ref. Data 1986, 15, 1087–1279.

Corresponding Authors *E-mail: [email protected] (A.M.M.). *E-mail: [email protected] (V.N.A.).


Page 10 of 20

Page 11 of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


11

Table 1.Summary of the rate coefficient measurements for the reactions O2(b1Σ ) + M. Ref.

Rate constant at temperatures 295–298 K

21 22 23 24 25

1.1×10–12 4×10–13 (7.0±0.3)×10–13 (4.5±2)×10–13 (6.1±0.9)×10–13

26

(9.3±1)×10–13

210–350

27

(9.31±0.6)×10–13

209–373

28

(8.24±1.03)×10–13

202–344

29

(8.17±0.5)×10–13

173–393

30 31 this work

~8.17×10–13 (4.66±0.16)×10–13 (7.3±0.2)×10

–13

21 22 25 32 33

1.1×10–13 7.5×10–14 (8.1±0.1)×10–14 7.3×10–14 (1.08±0.11)×10–13

28

(9.62±0.91)×10–14

this work

(8.8±0.5)×10–14

21 23 33

4.3×10–15 (4.5±0.5)×10–15 (3.74±0.44)×10–15

this work

(4.0±0.2)×10–15

Temperatur e range, K H2

297–800 500–1000 297–780 CH4

198–352 297–758 CO

297–800

21 22 34 35

7×10 1.85×10–13 (9.8±0.4)×10–14 (9.8±0.4)×10–14

600–1000

36

(10.6±1.4)×10–14

210–370

this work

(1.02±0.13)×10–13

(6.3±0.5)×10–12 exp

678±

(6.8±1.2)×10–12 exp

(8±2.5)×10–12 exp

+ ;:±>>

Not available –18

;;±8

Removal by H

Recommend Documents