Towards inherently safe reactors: Methane oxidation in a catalytic microreactor

I&EC 137

Goetz Veser, gveser@engr.pitt.edu, Chemical Engineering Department, University of Pittsburgh, 1249 Benedum Hall, Pittsburgh, PA 15261 and M Wartmann, Dept of Chem. Eng, University of Pittsburgh, 1249 Benedum Hall, Pittsburgh, PA 15261.
The sub-millimeter characteristic dimensions of catalytic microchannel reactors result in short transport pathways and large surface-to-volume ratios. We have previously shown that this can lead to complete quenching of gas-phase reactions in hydrogen oxidation due to radical-scavenging by the reactor walls. We are currently extending our studies to demonstrate the applicability of this concept for a broad range of reaction systems.

In the present contribution, we present results from reactive flow simulations using a two-dimensional boundary layer model with detailed surface and homogeneous elementary-step kinetics which demonstrate that catalytic methane oxidation can be conducted with complete suppression of gas-phase reactions, i.e. with inherently safe reactor operation, up to very high temperatures. In addition, complete suppression of prompt-NOx formation was observed.

These results confirm that microchannel reactors can open new perspectives in the design of a future generation of safe and environmentally clean processes for the production of chemicals and energy.