Thermal stability of n-dodecane : experiments and kinetic modelling

TL;DR

This study investigates the thermal decomposition of n-dodecane using experiments and an improved kinetic model, revealing detailed product distributions and mechanisms relevant for fuel cooling in hypersonic vehicle applications.

Contribution

It provides new experimental data and an enhanced kinetic model that includes aromatic compound formation and consumption during n-dodecane decomposition.

Findings

Main products include hydrogen, methane, ethane, and 1-alkenes.

Higher temperatures produce aromatic compounds like benzene and pyrene.

The improved model better predicts product formation across temperature ranges.

Abstract

The thermal decomposition of n-dodecane, a component of some jet fuels, has been studied in a jet-stirred reactor at temperatures from 793 to 1093 K, for residence times between 1 and 5 s and at atmospheric pressure. Thermal decomposition of hydrocarbon fuel prior the entrance in the combustion chamber is an envisaged way to cool the wall of hypersonic vehicles. The products of the reaction are mainly hydrogen, methane, ethane, 1,3-butadiene and 1-alkenes from ethylene to 1-undecene. For higher temperatures and residence times acetylene, allene, propyne, cyclopentene, 1,3-cyclopentadiene and aromatic compounds from benzene to pyrene through naphthalene have also been observed. A previous detailed kinetic model of the thermal decomposition of n-dodecane generated using EXGAS software has been improved and completed by a sub-mechanism explaining the formation and the consumption of aromatic compounds.