Gas-Phase Oxidation of a Propane-Propylene Mixture by Nitrous Oxide

The present study focuses on a new method for obtaining C2-C3 carbonyl compounds (ketones and aldehydes) by the gas-phase selective oxidation of a propane-propylene mixture using nitrous oxide (N2O). The oxidation is carried out without catalyst in the temperature range of 623-773 K at elevated pressure. The obtained results reveal that only propylene in the propane- propylene mixture reacts with nitrous oxide. The reaction proceeds by the nonradical mechanism involving the 1,3-dipolar cycloaddition of N2O to the C=C double bond of olefin. The main reaction products are acetone, propanal, and acetaldehyde. At 723 K and a pressure of 0.7 MPa, the total selectivity to these products amounts to 74.6%, the N2O conversion attains 74.5%, and the propylene conversion is 12.5%. An important feature of the reaction is the additional formation of methylcyclopropane with a selectivity of ca. 6%.