Reaction mechanisms for methane

1) Surface reactions : Catalytic combustion of hydrogen, carbon monoxide, and methane on platinum

Version: 1.2 (November 1995)
Evaluation: evaluated by comparison between calculated and experimentally determined catalytic ignition temperatures for a) stagnation point flows on an electrically heated platinum foils b) flows around an electrically heated platinum wires.
Reference: O. Deutschmann, R. Schmidt, F. Behrendt, J. Warnatz. Proc. Combust. Inst. 26 (1996) 1747-1754.

2) Surface reactions: Catalytic partial oxidation of methane on rhodium

Version: 1.0 (February 13, 2001)
Evaluation: evaluated on steady state experimental measurements of species profiles in short-contact-time reactor using honeycomb monoliths (Rh/Al2O3) at CH4/O2 = 1.4 – 2.3 and temperatures 800 – 1300K. 3D – Flow field simulation is coupled with detailed surface kinetics including thermal wall conductivity.
Reference: O. Deutschmann, R. Schwiedernoch, L.I. Maier, D. Chatterjee. Natural Gas Conversion VI, Studies in Surface Science and Catalysis 136, E. Iglesia, J.J. Spivey, T.H. Fleisch (eds.), p. 215-258, Elsevier, 2001 Version: 1.1 (2003)
Evaluation: evaluated on the transient light-off measurements of CH4/O2 mixtures in short-contact-time flow reactor (residence time 20 ms) using honeycomb monoliths (Rh/Al2O3) at the temperature range 385 – 1000K.
Reference: R. Schwiedernoch, S. Tischer, C. Correa, O. Deutschmann. Chem. Eng. Sci. 58 (2003), 633-642

3) Surface reactions: combined steam reforming and catalytic partial oxidation of methane on rhodium

Version: 2.0 (2009)
Evaluation: evaluated by comparison between calculated and experimentally determined conversion, selectivity, and species concentrations in a microchannel reactor at ambient pressure, temperature 673 – 973K, steam to carbon ratio (S/C) = 3 -8 by variation of the residence time inside the microchannels between 38 and 220 ms. Furthermore, the model is evaluated at supplemental feeding of products (H2, CO, CO2).
Reference: J. Thormann, L. Maier, P. Pfeifer, U. Kunz, K. Schubert, O. Deutschmann. International J. Hydrogen Energy 34 (2009), 5108-5120

4) Surface reactions: Methane reforming kinetics within a Ni-YSZ SOFC anode support

Version: 1.0 (January 2005)
Evaluation: evaluated by comparison between simulation data and species profiles measured at flow experiments specially designed to study the thermal methane reforming chemistry within porous Ni-YSZ anode of a solid-oxide fuel cell (SOFC).
Reference: E. Hecht, G.K. Gupta, H. Zhu. A.M. Dean, R.J. Kee, L. Maier, O. Deutschmann. Applied Catalysis A: General 295 (2005) 40–51 Version:1.2 (March 2006)
Evaluation:The mechanism Ni2005: E. Hecht, G.K. Gupta, H. Zhu, A.M. Dean, R.J. Kee, L. Maier, O. Deutschmann. Applied Catalysis A: General 295 (2005) 40–51 adjusted for thermodynamically consistency at the extended temperature range 500-2000°C for SOFC applications.
Reference: V.M. Janardhanan, O. Deutschmann. Journal of Power Sources 162 (2006), 1192-1202

5) Surface reactions: Reforming and oxidation of methane on nickel

Version: 2.0 (2011)
Evaluation:validated by comparison between simulated and experimentally determined selectivity and conversion for partial oxidation and steam reforming of methane in continues flow reactor over Ni coated monoliths at temperature range 600 – 1300K, S/C = 1.9 – 3.7. Surface kinetics is thermodynamically consistent for a temperature range 273 – 1273K.
Reference:L. Maier, B. Schädel, K. Herrera Delgado, S. Tischer, O. Deutschmann. Steam Reforming of Methane over Nickel: Development of a Multi-Step Surface Reaction Mechanism. Topics in Catalysis 54 (2011) 845-858.

6) Gas phase reactions: Total and partial oxidation of C1-4 alkanes in the high and medium temperature range

Version:1.0 (Spring 2005)
Evaluation:evaluated by comparison experiments and simulation related to ignition delay times, flame velocities, and concentration profiles of species for a wide range of conditions.
Reference: R. Quiceno, O. Deutschmann, J. Warnatz, European Combustion Meeting 2005. Louvain-la-Neuve, 3-6 April 2005, Belgian Section of the Combustion Institute paper, Chemical kinetics section, paper 29

7) Surface and gas phase reactions: Catalytic partial oxidation of methane over Pt gauze

Version: 1.1 (2006)
Evaluation:Gas-phase mechanism C1-4 2005: "R. Quiceno, O. Deutschmann, J. Warnatz, European Combustion Meeting 2005. Louvain-la-Neuve, 3-6 April 2005, Belgian Section of the Combustion Institute paper, Chemical kinetics section, paper 29" was reduced for CFD applications combined detailed homogeneous/heterogeneous kinetic model was evaluated by comparison between calculated and experimentally determined product composition in a Pt wire gauze reactor (1.3 bar, 700 - 1100K, CH4/O2 = 2.5, residence time 36s).
Reference:R. Quiceno, J.Perez-Ramirez, J. Warnatz, O. Deutschmann. Applied Catalysis A: General, 303 (2006) 166-176

8) Surface reactions: Pt-catalyzed conversion of automotive exhaust gases (NSC - NOx Storage Reduction Catalyst)

Version: 1.0 (2009)
Evaluation: evaluated by comparison between simulated and experimentally determined species concentrations in a flat bed reactor using a realistic model exhaust gas of a diesel engine for lean and rich phases including CO, CO2, O2, H2O, NO, NO2 and C3H6 species. Furthermore, the model is also applied for the simulation of emissions of hydrocarbons, CO, and NO from a gasoline engine (stoichiometric exhaust gas) in a dynamic engine test bench.
Reference: J. Koop, O. Deutschmann. Detailed surface reaction mechanism for Pt-catalyzed abatment of automotive exhaust gases. Appl. Catal.B: Environmental 91 (2009), 47-58

8) Surface reactions: Catalytic partial oxidation of iso-octane and propane over an alumina coated honeycomb monolith (Rh)

Version: 1.0 (2010)
Evaluation: evaluated by comparison between simulated and experimentally measured product composition in a flow reactor with Rh/Al2O3 monolith catalyst by variation of inlet temperatures and C/O ratio 0.8 - 2.0, residence time 40 ms.
Reference: M. Hartmann, L. Maier, O. Deutschmann. Catalytic Partial Oxidation of Iso-Octane over Rhodium Catalysts: An Experimental, Modeling, and Simulation Study. Combustion and Flame, 157 (2010) 1771-1782

9) Surface reactions: Steam reforming of hexadecane over a Rh/CeO2 catalyst in microchannel reactor

Version: 1.0 (2009)
Evaluation: evaluated by comparison between calculated and experimentally determined conversion, selectivity , and species concentrations in a microchannel reactor at ambient pressure, temperature 673 - 973K, steam to carbon ratio (S/C) = 3 -8 by variation of the residence time inside the microchannels between 38 and 220 ms. Furthermore, the model is evaluated at supplemental feeding of products (H2, CO, CO2).
Reference: J. Thormann, L. Maier, P. Pfeifer, U. Kunz, K. Schubert, O. Deutschmann. International J. Hydrogen Energy 34 (2009), 5108-5120

10) Surface reactions: Catalytic oxidation and steam/dry reforming of methane over rhodium

Version:2.0 (2015)
Evaluation: evaluated on steady-state experiments for partial oxidation, steam- and dry reforming of methane in stagnation flow reactor over Rh/Al2O3 catalyst at 298 - 1173K, 100 – 1100 mbar; comparison with experimentally measured species profiles in annular flow reactor (573 – 1123K) and spatial profile measurements along the foam structured Rh/Al2O3 monolith catalyst. Surface kinetics is thermodynamically consistent for a temperature range 273 – 1273K.
Reference:C. Karakaya, L. Maier, O. Deutschmann, Surface Reaction Kinetics for Oxidation and Reforming of CH4 over Rh/2O3 catalyst, International Journal of Chemical Kinetics, Vol. 48(3) (2016) pp. 144 - 160.

11) Surface reactions: Catalytic oxidation and steam/dry reforming of methane over nickel

Version:3.0 (2015)
Evaluation: is evaluated by comparison of numerical simulations with data derived from isothermal experiments in a flow reactor over a powdered nickel-based catalyst using varying inlet gas compositions and operating temperatures (373 - 1173K). Furthermore, the influence of hydrogen and water as co-feed on methane dry reforming with CO2 is also investigated. Surface kinetics is thermodynamically consistent for a temperature range 273 - 1273K.
Reference: K. Herrera Delgado, H. Stotz, L. Maier, S. Tischer, A. Zellner, O. Deutschmann. Surface Reaction Kinetics of Steam- and CO2-Reforming as well as Oxidation of Methane over Nickel-based Catalysts. Catalysts 5 (2015) 871-904.

12) Surface reactions: Catalytic oxidation of methane over reduced palladium

Version: 1.0 (2016)
Evaluation: evaluated based on experimentally axially space resolved concentration profiles at steady-state for partial and total oxidation of methane within a channel flow reactor over Pd/Al2O3 catalyst at 900 - 1100 K, 1013 mbar, C/O-ratios = 0.8 - 1.1, 80 vol.-% N2 dilution; comparison with experimentally reported light-off profiles in an annular flow reactor (900 - 1200 K) under fuel-lean conditions (C/O-ratio = 0.125) as well as experimentally reported species concentrations over a Pd-foil catalyst under fuel-rich conditions (C/O-ratio = 1.0) at different temperatures (950 - 1200 K). Surface kinetics is thermodynamically consistent for a temperature range 273 – 1400K.
Reference:H. Stotz, L. Maier, O. Deutschmann, Methane Oxidation over Palladium: On the Mechanism in Fuel-Rich Mixtures at High Temperatures, Topics in Catalysis: Catalysis and environmental protection, accepted (2016).

Catalyst

Fuel on Surface

Gasphase kinetics