High-temperature mid-IR absorption and reaction kinetics of 2-methyl-1,3-dioxolane: An experimental and theoretical study

This work reports the mid-IR spectroscopy and reaction kinetics of 2-methyl-1,3-dioxolane (2M13DO). We carried out spectroscopic measurements to deduce temperature-dependent absorption cross-sections 2M13DO over a broad wavelength range 8.4–10.5 ?m (950–1190 cm?1). For these measurements, we employed rapidly tuning MIRcat-QT™ laser that can be operated either at fixed or scanned mode wide regions. By operating wavelength, monitored decay behind reflected shock waves T5 = 1050–1400 K P5 0.7 2.6 bar. Our measured concentration time-histories allowed us directly extract overall rate coefficients for unimolecular decomposition using first-order law. did not observe any pressure dependence in coefficients, indicating is close high-pressure limit. employing W1U composite method, explored important pyrolysis pathways reactive potential energy surface. Three channels, namely, ? CH2CHOCH2CH2OH (IM1), 2CH3CHO (P3), CH3 + 1,3-dioxolan-2-yl (P4) were identified. Below 700 K, IM1 forming channel dominant, whereas CH3CHO formation dominant under our experimental conditions. Above 1500 radical (CH3+P4) takes other channels. At higher temperatures, contribution continually increases, accounting ? 99% 2000 K. used stochastic RRKM-ME model predict temperature k(T, P), time-resolved species profiles. theory showed excellent agreement with coefficients. These are first direct determination 2M13DO.