Abstract: A catalyst for improving combustion of fluid fuels which comprises three layers. An inner or core layer of complex oxides of a mixture of Mn, Ni, Co and Cu; an intermediate layer containing alumina and silicate and optionally silicon carbide and an outer layer comprising a fired mixture of a Pt--Pd,Rh alloy on Al.sub.2 O.sub.3, Mo--Al.sub.2 O.sub.3, mixed oxides of La--Sr--Co and at least one of Vanadium oxide on alumina and Ag on Alumina. The catalyst can contact the fluid fuel in a storage tank, in a pipeline or in a combustion chamber. The invention also comprises combustion engines which incorporate the described catalyst.

Abstract: A fluid fuel reforming ceramic catalyst comprising a core 2 of a complex oxide ceramic of transition metals, an intermediate layer 3 of an alumina-based silicate ceramic covering the core 2 and an outer layer 4 of a ceramic containing noble metals prepared by forming the core by firing the complex oxide ceramic of transition metals, coating the intermediate layer of the alumina-based silicate ceramic over the core, and coating the outer layer of the ceramic containing noble metals over the intermediate layer increases the octane number of fluid fuels, enhances their combustion efficiency, and decreases the noxious substances in exhaust gases.