Experimental and numerical study on the transient behavior of partial oxidation of methane in a catalytic monolith

Modeling of the Interactions Between Catalytic Surfaces and Gas-Phase

“…The very low oxygen concentration at the catalyst entrance leads to some formation of hydrogen in a region, where the oxygen concentration in the gaseous bulk phase is still sufficiently high to promote total oxidation. In general, the reaction sequence is very similar to the behavior observed for light hydrocarbons by many groups [10,78,[91][92][93]: after a short initial total oxidation zone leading to steam and CO 2 , the oxygen deficiency at the catalytic surface leads to the formation of hydrogen by steam reforming. Due to the high temperature of approximately 1,000°C, some remaining fuel is pyrolyzed by gasphase reactions to form the coke precursors ethylene and propylene (Fig.…”

“…Figure 3 shows the computed time-resolved temperature and species profiles in a single channel of the catalytic monolith (similar to the one shown in Fig. 1) and the temperature distribution of the solid structure during light-off of the reaction [78]. The numerical simulation is based on a two-dimensional simulation of the flow, temperature, and concentration fields in the catalytic channels using a 38-step catalytic reaction mechanism coupled with a transient three-dimensional simulation of the temperature of the solid structure [72,79].…”

“…Later due to the higher temperatures and the depletion of oxygen concentration, the formation of hydrogen is conducted by steam reforming over the entire catalyst except in the entrance region where oxygen is still available. When this simulation was conducted only the outlet composition could be measured and compared with the results [78]. In the last decade, in situ techniques have been developed to spatially resolve the species profiles and the catalyst states inside catalytic reactors.…”

Computational Fluid Dynamics Simulation of Catalytic Reactors

“…In particular oxidation reactions over noble metals have been modeled extensively such as of hydrogen [38][39][40][41][42][43][44] , CO [45][46][47] , and methane [31,[48][49][50][51][52] and ethane [22,26,53,54] over Pt, formation of synthesis gas over Rh [52,55] . Lately, mechanisms have been established for more complex reaction systems, for instance, three-way catalysts [56] or Chemical Vapor Deposition (CVD) reactors for the formation of diamond [57,58] , silica [59] , and nanotubes [60] .…”

“…This approach is the basis for the computer code DETCHEM MONOLITH [91] , and the temperature distribution of the solid structure during light-off [55] .…”