NOVEL MICRODESIGN OF OXIDATION CATALYSTS - PART 1 - GLASS CRYSTAL MICROSPHERES AS NEW CATALYSTS FOR THE OXIDATIVE CONVERSION OF METHANE

New catalysts designed as glass crystal microspheres were obtained as a result of coal and lignite combustion, hydrodynamic classification o f fly ash followed by magnetic separation. The physicochemical and cat alytic properties of three different systems of new catalysts were stu died by SEM, XRD and Mossbauer spectroscopy. The active component of t he new systems was shown to include alpha-Fe2O3 and a solid solution f ormed from magnetite and Mg(Mn)-ferrite. High-temperature eutectics (1 473-1673 K) on the base of calcium aluminosilicates are represented as a matrix material. The growth of the Fe2+ concentration in the spinel phase results in increase of selectivity of C-2-product formation in oxidative coupling of methane at 1123 K and in a decrease of catalytic activity of deep oxidation at 793 K. (C) 1998 Elsevier Science B.V. A il rights reserved.