AN INSILCO STUDY OF 1,1-DIFLUORO-2-METHOXYPROPANE REACTION MECHANISM WITH THE BROMINE MONOXIDE (BrO) RADICAL

  • Mohammed Abubakar Rufai Ahmadu Bello University, Zaria, Kaduna state.
  • Uzairu Adamu Ahmadu Bello University, Zaria, Kaduna state.
  • Shallangwa Gideon Ahmadu Bello University, Zaria, Kaduna state.
  • Sani Uba Ahmadu Bello University, Zaria, Kaduna state.

Resumo

An Insilco study was carried out on the thermochemistry, mechanism and kinetics of the Hydrogen abstraction reaction of 1,1-difluoro-2-methoxypropane (CH3CH(OCH3)CHF2) with the Bromine monoxide radical (BrO) using the Density Functional Theory (DFT) based M06-2X/6-311++G** method. The energy values were immediately improved via optimization at DFT/M06-2X/6-311++G(2df,2p) level (single-point calculations) of the reacting species involved. The Monte Carlo search on the investigating hydrofluoroether (HFE) showed nine conformers with the lowest global minimum conformer being predicted and considered for this work. The results of this study showed that the atmospheric oxidation reaction of CH3CH(OCH3)CHF2 with the BrO radical proceeded in four (4) plausible reaction routes. The  total experimental rate of 4.34*10-06 cm-3 molecule-1 sec-1 for HFE + BrO reaction was estimated with atmospheric lifetime (ALT)/global warming potential (GWP) of 1.80 years and 165.30 respectively. The 3D potential energy surfaces (PES) for the reaction was however constructed at absolute temperature of 298.15 K.

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Publicado
2019-03-08
Como Citar
RUFAI, M. A.; ADAMU, U.; GIDEON, S.; UBA, S. AN INSILCO STUDY OF 1,1-DIFLUORO-2-METHOXYPROPANE REACTION MECHANISM WITH THE BROMINE MONOXIDE (BrO) RADICAL. The Journal of Engineering and Exact Sciences, v. 5, n. 1, p. 0090-0099, 8 mar. 2019.
Seção
Physical Chemistry