Molecular and Temperature Aspects in Catalytic Partial Oxidation of Methane

Heterogeneous stoichiometric oxidation and catalytic partial oxidation (CPO) of methane are studied at the surfaces of MgO, α-Al2O3, and CeO2 containing small Rh clusters. Stoichiometric reactions are linked to a repeating loop that has produced the CPO of methane at temperatures lower than 773 K with selectivity close to 100%. These reactions occur through the formation and the thermal decomposition of hydridocarbonyl Rh clusters. Molecular aspects of stoichiometric reactions are compared with those produced under stationary conditions with flows of premixed CH4 and O2 at very short residence time. Comparisons show that collisions between hydridocarbonyl clusters and gaseous O2 produce CO2 and H2O. IR thermography maps collected during short residence time CPO and gaseous temperature measurements are also reported. They show the existence of nonlocal thermal equilibrium between the solid and gaseous phases.

[1]  Lanny D. Schmidt,et al.  Catalytic partial oxidation of natural gas to syngas , 1995 .

[2]  Heinz Heinemann,et al.  Partial oxidation of methane to syngas over Co/MgO catalysts. Is it low temperature? , 1993 .

[3]  Daniel A. Hickman,et al.  Synthesis gas formation by direct oxidation of methane over Pt monoliths , 1992 .

[4]  Malcolm L. H. Green,et al.  Partial oxidation of methane to synthesis gas, and carbon dioxide as an oxidising agent for methane conversion , 1992 .

[5]  A. Poater,et al.  Catalysis Science and Technology , 2022 .

[6]  F. Basile,et al.  Ni/Mg/Al anionic clay derived catalysts for the catalytic partial oxidation of methane : Residence time dependence of the reactivity features , 1998 .

[7]  C. Paparizos,et al.  Production of synthesis gas , 1993 .

[8]  L. Basini,et al.  Molecular mechanisms in partial oxidation of methane on Ir/α-Al2O3: reactivity dependence on catalyst properties and transport phenomena limitations , 1996 .

[9]  J. Lunsford,et al.  Are the equilibrium concentrations of carbon monoxide and hydrogen exceeded during the oxidation of methane over a nickel/ytterbium oxide catalyst? , 1993 .

[10]  J. Hochmuth.  Catalytic partial oxidation of methane over a monolith supported catalyst , 1992 .

[11]  V. Choudhary,et al.  Nonequilibrium Oxidative Conversion of Methane to CO and H2 with High Selectivity and Productivity over Ni/Al2O3 at Low Temperatures , 1993 .

[12]  K. Kunimori,et al.  Molecular beam study of C2H4 oxidation on platinum: IR chemiluminescence of the CO and CO2 products , 1995 .

[13]  L. Schmidt,et al.  Olefins by Catalytic Oxidation of Alkanes in Fluidized-Bed Reactors , 1995 .

[14]  L. Basini,et al.  DRIFT and mass spectrometric experiments on the chemistry and catalytic properties of small Ir clusters at the surfaces of polycrystalline α-Al2O3 , 1994 .

[15]  R. Peck,et al.  Flame Stabilization and Multimode Heat Transfer in Inert Porous Media: A Numerical Study , 1990 .

[16]  G. Froment,et al.  Reaction Mechanism and Role of the Support in the Partial Oxidation of Methane on Rh/Al2O3 , 1996 .

[17]  Felix Jiri Weinberg,et al.  Advanced combustion methods , 1986 .

[18]  A. Trovarelli,et al.  Catalytic Properties of Ceria and CeO2-Containing Materials , 1996 .

[19]  C. Garland,et al.  Infrared Studies of Carbon Monoxide Chemisorbed on Rhodium , 1957 .

[20]  Paul M. Witt,et al.  Effect of Flow Rate on the Partial Oxidation of Methane and Ethane , 1996 .

[21]  John R. Howell,et al.  Combustion of hydrocarbon fuels within porous inert media , 1996 .

[22]  M. Baerns,et al.  Rhodium-catalyzed partial oxidation of methane to CO and H2. In situ DRIFTS studies on surface intermediates , 1994 .

[23]  L. Schmidt,et al.  Production of Syngas by Direct Catalytic Oxidation of Methane , 1993, Science.

[24]  Daniel A. Hickman,et al.  Steps in CH4 oxidation on Pt and Rh surfaces: High‐temperature reactor simulations , 1993 .

[25]  J. Yates,et al.  Spectroscopic study of the interconversion of chemisorbed surface species: The reaction RhI(CO)2 + CO → Rh1(CO)3 , 1984 .

[26]  J. Yates,et al.  Infrared spectra of chemisorbed CO on Rh , 1979 .

[27]  Shigeru Tada,et al.  Experimental study on combustion in porous media with a reciprocating flow system , 1997 .

[28]  G. Gavalas,et al.  Structure and Activity of NiO/α-Al_2O_3 and NiO/ZrO_2 Calcined at High Temperatures I. Structure , 1984 .

[29]  Malcolm L. H. Green,et al.  Partial oxidation of methane to synthesis gas using carbon dioxide , 1991, Nature.

[30]  Malcolm L. H. Green,et al.  Recent advances in the conversion of methane to synthesis gas , 1995 .

[31]  J. Yates,et al.  Rhodium-carbon monoxide surface chemistry: the involvement of surface hydroxyl groups on alumina and silica supports , 1988 .

[32]  Y. Matsumura,et al.  Oxidative methane conversion to carbon monoxide and hydrogen at low reactor wall temperatures over ruthenium supported on silica , 1994 .

[33]  J. Wey,et al.  Infrared spectroscopy at high pressure: Interaction of CO with oxidized Rh/Al2O3 , 1992 .

[34]  L. Schmidt,et al.  The role of boundary layer mass transfer in partial oxidation selectivity , 1992 .

[35]  J. Basset,et al.  Surface-supported metal cluster carbonyls. Chemisorption decomposition and reactivity of hexadecacarbonylhexarhodium supported on alumina, silica-alumina, and magnesia , 1979 .

[36]  K. Kunimori,et al.  Infrared chemiluminescence of CO and CO2 produced by molecular-beam surface reactions , 1993 .

[37]  L. Schmidt,et al.  Effect of pressure on three catalytic partial oxidation reactions at millisecond contact times , 1995 .

[38]  L. Schmidt,et al.  Ethylene formation by oxidative dehydrogenation of ethane over monoliths at very short contact times , 1993 .

[39]  G. Samsonov,et al.  The Oxide Handbook , 1973 .

[40]  J. Schwartz,et al.  Partial Oxidation of Olefins by Molecular Oxygen Catalyzed by (Alumina)Rh(O2) , 1991 .

[41]  M. Poirier,et al.  Partial Oxidation of Methane over a Praseodymium/Ruthenium Pyrochlore Catalyst , 1992 .

[42]  F. Weinberg,et al.  Combustion Temperatures: The Future? , 1971, Nature.

[43]  J. Lunsford,et al.  Partial oxidation of methane to carbon monoxide and hydrogen over a Ni/Al2O3 catalyst , 1991 .

[44]  L. Basini,et al.  Molecular Aspects in Syn-Gas Production: The CO2-Reforming Reaction Case , 1995 .

[45]  V. Choudhary,et al.  Low-temperature catalytic selective partial oxidation of methane to carbon monoxide and hydrogen over nickel/ytterbium sesquioxide , 1992 .

[46]  C. Rice,et al.  The oxidation state of dispersed Rh on Al2O3 , 1981 .

[47]  V. Choudhary,et al.  Selective Oxidation of Methane to CO and H2 over Ni/MgO at Low Temperatures , 1992 .