Manganese oxide water—gas shift catalysts initial optimization studies

Abstract

A study of cobalt manganese oxide, copper manganese oxide and iron manganese oxide catalysts for the water—gas shift reaction is reported. In contrast to the other two oxide formulations the iron manganese oxide catalyst was not particularly active for this reaction, even at temperatures as high as 400°C. Alkali promoted cobalt manganese oxide and copper manganese oxide catalysts were found to be very active at temperatures over 300°C. Both catalysts gave significantly improved performance when compared to the current industrially utilized high-temperature shift catalyst, and initial optimization studies of these formulations are reported and discussed. Copper manganese catalysts require a manganese rich formulation for optimal performance, whereas cobalt manganese catalysts require a cobalt rich formulation. An added advantage of the copper manganese catalysts is that no by-product hydrocarbons were formed under a wide range of experimental conditions. Structural studies of the catalysts are also reported, and it is observed that the catalysts contain the metal supported on MnO as well as metal in solid solution within the MnO matrix.