An experimental and kinetic modeling study on dimethyl carbonate (DMC) pyrolysis and combustion

Dimethyl carbonate (DMC) is a promising oxygenated additive or substitute for hydrocarbon fuels, because of the absence of C-C bonds and the large oxygen content in its molecular structure. To better understand its chemical oxidation and combustion kinetics, flow reactor pyrolysis at different pressures (40, 200 and 1040 mbar) and low-pressure laminar premixed flames with different equivalence ratios (1.0 and 1.5) were investigated. Mole fraction profiles of many reaction intermediates and products were obtained within estimated experimental uncertainties. From theoretical calculations and estimations, a detailed kinetic model for DMC pyrolysis and high-temperature combustion consisting of 257 species and 1563 reactions was developed. The performance of the kinetic model was then analyzed using detailed chemical composition information, primarily from the present measurements. In addition, it was examined against the chemical structure of an opposed-flow diffusion flame, relying on global combustion properties such as the ignition delay times and laminar burning velocities. These extended comparisons yielded overall satisfactory agreement, demonstrating the applicability of the present model over a wide range of high-temperature conditions.