Abstract: Highly active and selective Ni-based catalysts for partial oxidation of methane (POM) to syngas (CO/H,) have been studied and developed. Spectroscopic characterization by XRD, XPS, EPR, etc. demonstrated that under the POMreaction conditions, the Ni-components of the catalysts investigated were reduced and enriched on the surface to form metallic Ni0-phase. Acomparative study of the first series of transition-metals showed that only Ni and Co have a high POMactivity and selectivity, whereas the others (including Mn, Fe, Cu, etc.) give mainly complete combustion products, Co, and H₂O. The results favor the following viewpoints: the PoMactivity is related with the rapidly changeable valence transitionmetal sites, M0/M²⁺(e. g. Ni0/Ni²⁺), on the surface of the functioning catalysts;the transition-metal sites in zero-valence state seem to be responsible for the activation and dehydrogenation of methane by homolytic splitting of its C-Hbonds on these sites. and the nature of rapidly changeable valence of the active sties is requisite for activation and rapid conversion of dioxygen.

Key words: Partial oxidation of methane, Syngas, Ni-based catalysts