Physicochemical and catalytic properties of glass crystal catalysts for the oxidation of methane

Magnetic microspheres and cenospheres recovered from fuel ashes were studie d by SEM, XRD, electron probe microanalysis, chemical analysis and Mossbaue r spectroscopy. The magnetic microspheres were shown to consist of a crysta l phase based on a solid solution of Fe3O4-Mg, Mn, Ca-ferrite, alpha-Fe2O3 and a glass phase composed of calcium ferrite, fayalite, wollastonite, ferr ous olivines and mullite. The morphology of globules and size of crystallit es of active phase were established to depend on the basicity of the glass phase. It was shown that catalytic activity of magnetic microspheres and ce nospheres in oxidative conversion of methane is determined by component con taining iron and depends on its accessibility and distribution on the surfa ce. (C) 2000 Elsevier Science B.V. All rights reserved.