Direct oxidation of methane to methanol over proton conductor/metal mixed catalysts

Abstract The intermediate-temperature and low-pressure production of methanol from methane in a one-pass process was investigated using a micro- or nanosized electrocatalyst system. The powdered catalyst was prepared by mixing proton-conducting Sn 0.9 In 0.1 P 2 O 7 particles with high-activity Pd–Au–Cu/C particles to provide numerous electrolyte–electrode interfaces as reaction sites for methane oxidation. For a feed mixture of H 2 O, O 2 , and methane, a local electrochemical cell can be formed at the electrode–electrolyte interface: H 2 O → 1/2O 2  + 2H +  + 2e − at the anode site; O 2  + CH 4  + 2H +  + 2e −  → CH 3 OH + H 2 O at the cathode site. In addition, the electrode also functions as a lead wire that short-circuits the cell. Therefore, the overall reaction can be expected to be CH 4  + 1/2O 2  → CH 3 OH. The series of reactions successfully resulted in reduction in the temperature for initiation of methane oxidation to 250 °C and increased the methanol yield while maintaining a very high selectivity toward methanol for temperatures up to 400 °C.

[1]  G. Somorjai,et al.  A kinetic study of partial oxidation of methane with nitrous oxide on a molybdena-silica catalyst , 1985 .

[2]  N. Spencer.  Partial oxidation of methane to formaldehyde by means of molecular oxygen , 1988 .

[3]  L. Wenger,et al.  X-Ray photoelectron spectroscopy (XPS) studies of copper–sodium tellurite glasses , 2003 .

[4]  K. Otsuka,et al.  Oxygenation of alkanes and aromatics by reductively activated oxygen during H2-O2 cell reactions , 2000 .

[5]  G. Hutchings,et al.  Solvent-Free Oxidation of Primary Alcohols to Aldehydes Using Au-Pd/TiO2 Catalysts , 2006, Science.

[6]  R. M. Allen,et al.  Iron−Sulfur Proteins with Nonredox Functions , 1996 .

[7]  T. Hibino,et al.  H/D Isotope Effect on Electrochemical Pumps of Hydrogen and Water Vapor Using a Proton‐Conductive Solid Electrolyte , 1993 .

[8]  K. Klier,et al.  Partial Oxidation of Methane , 1986 .

[9]  Ayusman Sen,et al.  A Highly Catalytic Bimetallic System for the Low-Temperature Selective Oxidation of Methane and Lower Alkanes with Dioxygen as the Oxidant , 1997 .

[10]  T. Hibino,et al.  Direct oxidation of methane to methanol at low temperature and pressure in an electrochemical fuel cell. , 2008, Angewandte Chemie.

[11]  Ye Wang,et al.  Catalytic Oxidation of Methane to Methanol with H2-O2 Gas Mixture at Atmospheric Pressure , 1995 .

[12]  J. Fierro,et al.  Partial oxidation of methane into C1-oxygenates: role of homogeneous reactions and catalyst surface area , 2001 .

[13]  M. Bañares,et al.  Comparison of Silica-Supported MoO3and V2O5Catalysts in the Selective Partial Oxidation of Methane , 1996 .

[14]  P. Cañizares,et al.  Partial oxidation of methane to formaldehyde over W/SiO2 catalysts , 1998 .

[15]  T. Ishihara,et al.  Synthesis of hydrogen peroxide by direct oxidation of H2 with O2 on Au/SiO2 catalyst , 2005 .