Kinetics of the gas-phase reaction of hydroxyl radicals with trimethyl phosphate over the 273-837 K temperature range

Authors

P. V. Koshlyakov, Voevodsky Institute of Chemical Kinetics and Combustion Siberian Branch of the Russian Academy of Sciences
D. A. Barkova, Voevodsky Institute of Chemical Kinetics and Combustion Siberian Branch of the Russian Academy of Sciences
I. E. Gerasimov, Voevodsky Institute of Chemical Kinetics and Combustion Siberian Branch of the Russian Academy of Sciences
E. N. Chesnokov, Voevodsky Institute of Chemical Kinetics and Combustion Siberian Branch of the Russian Academy of Sciences
Xiaokai Zhang, New Jersey Institute of Technology
L. N. Krasnoperov, New Jersey Institute of Technology

Document Type

Article

Publication Date

4-15-2021

Abstract

The kinetics of the reaction of hydroxyl radical (OH) with trimethyl phosphate (CH3O)3PO (TMP) (reaction (1)) OH + TMP → products (1) was studied at the bath gas (He) pressure of 1 bar over the 273-837 K temperature range. Hydroxyl radicals were produced in fast reactions of electronically excited oxygen atoms O(¹D) with either H2O or H2. Excited oxygen atoms O(¹D) were produced by photolysis of ozone, O3, at 266 nm (4^thharmonic of Nd:YAG laser) over the 273-470 K temperature range and by photolysis of N2O at 193 nm (ArF excimer laser) over the whole temperature range including the elevated temperature range 470-837 K. The reaction rate constant exhibits a V-shaped temperature dependence, negative in the low temperature range, 273-470 K (the rate constant decreases with temperature), and positive in the elevated temperature range, 470-837 K (the rate constant increases with temperature), with a turning point at 471 K. The rate constant could be fairly well fitted with the three parameter modified Arrhenius expression,k1= 7.52 × 10⁻¹⁸(T/298)⁹exp(34 367 J mol⁻¹/RT) cm³per molecule per s (273-837 K). Previously, only one indirect experimental measurement at a single (ambient) temperature was available. The temperature dependence over an extended temperature range obtained in this study together with the peculiar V-shaped temperature dependence will have an impact on the modelling of the flame inhibition by phosphates as well on the further understanding of the mechanisms of elementary chemical reactions.

Identifier

85104283369 (Scopus)

Publication Title

Rsc Advances

External Full Text Location

https://doi.org/10.1039/d1ra00911g

e-ISSN

20462069

First Page

14121

Last Page

14131

Issue

23

Volume

11

Grant

19-73-20060

Fund Ref

Russian Science Foundation

Recommended Citation

Koshlyakov, P. V.; Barkova, D. A.; Gerasimov, I. E.; Chesnokov, E. N.; Zhang, Xiaokai; and Krasnoperov, L. N., "Kinetics of the gas-phase reaction of hydroxyl radicals with trimethyl phosphate over the 273-837 K temperature range" (2021). Faculty Publications. 4174.
https://digitalcommons.njit.edu/fac_pubs/4174