Modeling the Synthesis of Nitrous Oxide in a Microchannel Reactor: Effect of Parameters on Temperature Regimes and Capacity

A study on the synthesis of nitrous oxide via the selective oxidation of ammonia in a microreactor in the form of a metallic disk with cylindrical channels filled with a manganese–bismuth oxide catalyst has been. A 3D mathematical model is presented for this microreactor that considers the transfer of mass and axial and radial heat, the catalytic reactions, the change they produce in the volume of the reaction mixture, the transfer of heat between the disk and the channels, and the heat conductivity of the disk. Parameters are determined that ensure the maximum nitrous oxide production with allowance for the limitations of temperature in the microreactor channels. The highest efficiency of nitrous oxide production is attained at an outer reactor edge temperature of 370°C and an inlet ammonia concentration of 20 vol %. The production capacity per unit catalyst volume in the microreactor is nearly 1.5 times higher than in a tubular reactor, and the maximum temperature corresponds to the level that provides the best process selectivity toward nitrous oxide.