Nanostructured Spinel Ferrites for Catalytic Combustion of Gasoline Vapors

Abstract

Effect of partial substitution of Fe3+ with Sc3+ ions, in Ni–Co spinel nanoferrite, synthesized by self-combustion method, using polyvinyl alcohol as colloidal medium, on the structural and catalytic properties for the combustion of Pb-free gasoline vapors is studied. Average crystallite size decreases and specific surface area increases with increasing Sc content. Catalytic properties are influenced by the nature of cations from spinel structure and nanoparticle surface. The catalytic activity improves with increasing Sc3+ content. The Ni0.5Co0.5Sc0.2Fe1.8O4 ferrite was found to be the most active catalyst and can be a good candidate for catalytic combustion of air-diluted vapors of Pb-free gasoline at moderate temperatures (250–500 °C). High performance activity of ferrite with maximum substitution of Sc is also accompanied by favorable structure of sample (granulation, porosity, specific surface area), resulted from its preparation method.