Cordierite-like mixed oxide monolith for ammonia oxidation process

The paper deals with modeling of a two-stage catalytic system for ammonia oxidation in an UKL-7 plant, preparation and characterization of cordierite-like honeycomb monoliths (similar to 230 cpsi) modified with (Mn, Co, Fe,V, Bi)O-x oxides as the secondary catalysts. The NO yield for as prepared monoliths was shown to depend not only on the testing temperature, nature and content of the active oxides but also on the cordierite crystallinity degree and on the inlet NH3 concentration. The best data on NO yield (>80%) at 880-900 degrees C were obtained with the iron and cobalt based modified monoliths used as the secondary catalysts in the two-stage catalytic system. The data obtained by modeling indicated the possibility to use 8 (instead of 12) gauzes and one layer of as prepared cordierite-like catalysts in the UKL-7 plant to provide the NO yield typical of 12 gauzes. (C) 2009 Elsevier B.V. All rights reserved.