Modeling heterogeneous/homogeneous reactions and transport coupling for catalytic combustion of methyl chloride over a Mn-based catalyst
- Yale Univ., New Haven, CT (United States). Dept. of Chemical Engineering
- Automated Analysis Corp., Peoria, IL (United States)
- Yale Univ., New Haven, CT (United States). Dept. of Mechanical Engineering
The effect of boundary-layer flow and heterogeneous/homogeneous reaction chemistry in determining product selectivity for catalytically promoted oxidation of ultralean CH{sub 3}Cl over a Mn-based catalyst was investigated numerically. This work has relevance to modeling of more general catalytic combustion systems in defining the importance of transport mid chemistry interactions. In this study, the authors find that the presence of Mn-based catalyst can significantly decrease the temperature necessary to achieve a given conversion of CH{sub 3}Cl. The numerical study of the experiment used plug-flow, lumped-parameter transport, and laminar-flow models with detailed gas-phase chemistry. These flow models coupled with gas-phase reaction mechanisms from the literature and an experimentally determined surface reaction rate were used to illustrate heterogeneous/homogeneous reaction coupling and how it is influenced by transport. Kinetic modeling shows that the heterogeneous and homogeneous interaction occurs through CH{sub 3}Cl decomposition on the surface that initiates gas-phase reaction. For the slower velocity, there is small difference in plug-flow model and detailed laminar boundary-layer model predictions. The difference in prediction between flow models becomes larger at the high velocity, with shorter residence time, where the higher surface temperature needed for equivalent conversion causes surface reaction products to be converted before, they can be transported to the bulk. The important parameter for modeling heterogeneous/homogeneous interactions is the Damkoehler number with respect to gas-phase consumption of species produced by surface reaction.
- OSTI ID:
- 93175
- Report Number(s):
- CONF-940711-; TRN: IM9537%%218
- Resource Relation:
- Conference: 25. international symposium on combustion, Irvine, CA (United States), 31 Jul - 5 Aug 1994; Other Information: PBD: 1994; Related Information: Is Part Of Twenty-fifth symposium (international) on combustion; PB: 1838 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
The interaction of high-speed turbulence with flames: Turbulent flame speed
Two-dimensional modelling for catalytically stabilized combustion of a lean methane-air mixture with elementary homogeneous and heterogeneous chemical reactions