Abstract: A catalyzer is provided for promoting chemical reactions, such as the reaction between ammonia and air to produce nitrogen monoxide which, in turn, can be used to manufacture nitric acid or the purification of flue gas from incineration plants. The catalyzer is made by forming a mixture of a combustible pore forming substance, such as a polymer, vegetable material or graphite, and a ceramic material, such as alumina, zirconia, titanium dioxide, silica, tungsten carbides, silicon nitrides and mixtures thereof, and thermally spraying this mixture onto a support net to result in a net having porous ceramic deposited thereon.