The pyrolysis and oxidation of diethyl ether (DEE) has been studied at pressures from 1 to 4 atm and temperatures of 900-1900 K behind reflected shock waves. A variety of spectroscopic diagnostics have been used, including time-resolved infrared absorption at 3.39 mum and time-resolved ultraviolet emission at 431 nm and absorption at 306.7 nm. In addition, a single-pulse shock tube was used to measure reactant, intermediate, and product species profiles by GC samplings at different reaction times varying from 1.2 to 1.8 ms. A detailed chemical kinetic model comprising 751 reactions involving 148 species was assembled and tested against the experiments with generally good agreement. In the early stages of reaction the unimolecular decomposition and hydrogen atom abstraction of DEE and the decomposition of the ethoxy radical have the largest influence. In separate experiments at 1.9 atm and 1340 K, it is shown that DEE inhibits the reactivity of an equimolar mixture of hydrogen and oxygen (1% of each).

Pyrolysis and oxidation of acetaldehyde were studied behind reflected shock waves in the temperature range 1000-1700 K at total pressures between 1.2 and 2.8 atm. The study was carried out using the following methods, (1) time-resolved IR-laser absorption at 3.39 µm for acetaldehyde decay and CH-compound formation rates, (2) time-resolved UV absorption at 200 nm for CH 2 CO and C 2 H 4 product formation rates, (3) time-resolved UV absorption at 216 nm for CH 3 formation rates, (4) time-resolved UV absorption at 306.7 nm for OH radical formation rate, (5) time-resolved IR emission at 4.24 µm for the CO 2 formation rate, (6) time-resolved IR emission at 4.68 µm for the CO and CH 2 CO formation rate, and (7) a single-pulse technique for product yields. From a computer-simulation study, a 178-reaction mechanism that could satisfactorily model all of our data was constructed using new reactions, CH 3 CHO (+M) → CH 4 + CO (+M), CH 3 CHO (+M) → CH 2 CO + H 2 (+M),

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