Promotion of Fe3O4/Cr2O3 high temperature water gas shift catalyst

The promotion of Fe3O4/Cr2O3 high temperature water gas shift catalysts is described and discussed. Catalysts containing 2 wt% B, Cu, Ba, Pb, Hg and Ag are prepared by co-precipitation. B is found to poison the activity slightly whereas the other additives did increase the activity, with the relative order being Hg > Ag, Ba > Cu > Pb > unpromoted > B. The promoters decrease the activation energy of the catalyst, but the data give a linear relationship for the Constable-Cremer plot and it is concluded that CO adsorption is an important factor controlling activity. (C) 2002 Elsevier Science B.V. All rights reserved.