Thermochemistry and kinetics of the α-hydroxyethyl radical + O2 reaction in ethanol combustion

Document Type

Conference Proceeding

Publication Date

1-1-2007

Abstract

Bioethanol is emerging as a component that will be increasingly blended into traditional petroleum-derived gasoline. It is important that we have accurate kinetic models for the combustion of ethanol in order to better understand the impact of this renewable fuel blend component in current and future engines. We have studied the reaction of the α-hydroxyethyl radical with O2 using theoretical density functional theory and ab initio methods. A detailed potential energy surface for this reaction is presented, with rate parameters calculated for each reaction step from transition state theory. The barrier-less α-hydroxyethyl + O2 association reaction is treated using variational transition state theory (VTST) for forward and reverse reaction kinetics, and is compared to the analogous hydroxymethyl + O2 association process. The chemically activated hydroxyethyl + O2 system is modeled using quantum Rice-Ramsperger-Kassel (QRRK) theory. With master equation analysis for falloff. The α-hydroxyethyl + O2 reaction proceeds almost exclusively to acetaldehyde + HO2 via a low-barrier H2O elimination from the hydroxyethylpeoxy adduct. The introduction of the rate constants presented in this study into existing reaction mechanisms should lead to better kinetic models for ethanol combustion. Preliminary analysis for the & beta;-hydroxyethyl radical + O2 reaction is also presented.

Identifier

84946550536 (Scopus)

ISBN

[9781604239454]

Publication Title

Fall Technical Meeting of the Eastern States Section of the Combustion Institute 2007 Chemical and Physical Processes in Combustion

First Page

114

Last Page

128

This document is currently not available here.

Share

COinS