New reaction classes in the kinetic modeling of low temperature oxidation of n-alkanes

CATEGORY: ALKANE 
New reaction classes in the kinetic modeling of low temperature oxidation of n-alkanes

Type	Journal Article
Author	Eliseo Ranzi
Author	Carlo Cavallotti
URL	http://www.sciencedirect.com/science/article/pii/S0010218014003848
Publication	Combustion and Flame
Abstract	Recent literature describes a large number of intermediate products from the low temperature oxidation of hydrocarbon fuels in jet stirred reactors. The new information focuses on systematic deviations between model predictions and experimental measurements, both in oxygenated species and in fuel conversion at very low temperatures. The discrepancies are largely reduced by including new reaction classes in the oxidation mechanism. Successive H-abstraction and molecular reactions of hydroperoxide species play a significant role at very low temperatures, in competition with the chain branching decomposition reactions. Several recombination and disproportionation reactions of peroxy radicals are interesting, as well, in explaining some intermediate oxygenated components. Authors review the ability of these novel reaction classes to explain the formation of oxygenated species, such as organic acids and dicarbonyl species. Rate constants were determined using similarity and analogy rules for consolidated reactions, while theoretical calculations were performed to determine preliminary estimates for reaction channels lacking a reference reaction. Detailed comparisons with several experimental data of propane and n-butane oxidation at low temperatures support these assumptions.