Oxidative Conversion of Methane. Effect of Catalyst and Perspective Directions of Reaction

The well-known MnNaW catalysts based on SiO2 for oxidative condensation of methane (OCM) were synthesized by various methods, characterized by X-ray diffractometry (XRD), scanning electron microscopy with energy dispersive elemental analysis (SEM/EDX), electron magnetic resonance (EMR) spectroscopy, N2 adsorption-desorption measurements, and tested as OCM catalysts at atmospheric pressure to convert into a mixture of ethylene + carbon oxides for further hydroformylation to propylene. The structural and catalytic features of the synthesized systems are discussed. The necessity of using mainly X-ray diffraction, Raman, and EMR methods for studying catalysts in situ mode in combination with online MS analysis of gas-phase reaction products to establish the nature of catalytically active phases, centers, their mechanism of functioning, activation of CH4 with the formation of C-C bond for the synthesis of hydrocarbons C2 and C2+ is considered.