Bond Energy Effects in Methane Oxidative Coupling on Pyrochlore Structures

• Published in: Journal of catalysis Vol. 140; no. 2; pp. 328 - 334
• Main Authors: Petit, C., Kaddouri, A., Libs, S., Kiennemann, A., Rehspringer, J.L., Poix, P.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.04.1993; Elsevier
• Subjects: 10 SYNTHETIC FUELS; 100200 - Synthetic Fuels- Production- (1990-); 400201 - Chemical & Physicochemical Properties; ALKANES; Catalysis; CATALYSTS; Catalysts: preparations and properties; CATALYTIC EFFECTS; CHALCOGENIDES; CHEMICAL BONDS; CHEMICAL REACTION YIELD; CHEMICAL REACTIONS; Chemistry; COHERENT SCATTERING; DIFFRACTION; DIMERIZATION; ELEMENTS; EUROPIUM COMPOUNDS; EUROPIUM OXIDES; Exact sciences and technology; GADOLINIUM COMPOUNDS; GADOLINIUM OXIDES; General and physical chemistry; HYDROCARBONS; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; METHANE; MINERALS; NONMETALS; ORGANIC COMPOUNDS; OXIDATION; OXIDES; OXYGEN; OXYGEN COMPOUNDS; POLYMERIZATION; PYROCHLORE; RARE EARTH COMPOUNDS; SAMARIUM COMPOUNDS; SAMARIUM OXIDES; SCATTERING; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; TIN COMPOUNDS; TIN OXIDES; TITANIUM COMPOUNDS; TITANIUM OXIDES; TRANSITION ELEMENT COMPOUNDS; X-RAY DIFFRACTION; YIELDS; ZIRCONIUM COMPOUNDS; ZIRCONIUM OXIDES; Methane; Catalytic reaction; Hydrocarbon; Tin Samarium Oxides Mixed; Metal Oxides; Experimental study; Oxidative coupling; Pyrochlore type compound; Characterization; Heterogeneous catalysis; Transition metal Oxides; Sol gel process; Preparation; Lanthanide Transition metal Oxides Mixed; Catalyst; Lanthanide Oxides
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1006/jcat.1993.1087

Compounds of general formula A2B2O7 have been characterized by X-ray diffraction and tested for catalytic activity in oxidative coupling of methane. Calculations of the rare earth-oxygen (AO) and cocation-oxygen (BO) bond energies provide a new way to estimate the influence of bulk parameters on the formation of C2 hydrocarbons. The observed values of C2 yields on A2B2O7 catalysts (A = Sm, Gd or Eu) (B = Ti, Zr, or Sn) indicate that they increase with decreasing cocation-oxygen bond energy. The best of these systems (Sm2Sn2O7) gives a C2 yield amounting to 20% at 973 K.