Novel regenerable catalyst-reagents, and a new and improved process utilizing said regenerable catalyst-reagents, for the conversion, and oligomerization of hydrocarbons, notably methane, at relatively low temperatures to produce products rich in ethylene or benzene, or both, usually in admixture with other hydrocarbons; and process for the regeneration of said catalyst-reagents. (a) The catalyst-reagents are multi-functional and are comprised of (1) a Group VIII noble metal having an atomic number of 45 or greater, nickel, or a Group I-B noble metal having an atomic number of 47 or greater; (2) a Group VI-B metal oxide which is capable of being reduced to a lower oxide, or admixture of metal oxides which includes one or more of such metal oxides; and, (3) a Group II-A metal or alkaline-earth metal, composited with a suitably passivated, spinel-coated refractory support, notably an inorganic oxide support, preferably alumina.