Catalysts based on inverse CeO2/CuO configurations employed for preferential oxidation of CO in a H-2-rich stream have been explored with respect to optimization of preparation parameters like calcination temperature and atmosphere. For this purpose, the catalysts precursors prepared by microemulsion have been characterized by TG-DTA, DRIFTS and XRD in order to select most adequate conditions. Selected specimens were further analysed by S-BET measurements as well as with respect to catalytic and redox properties by activity measurements and H-2-TPR tests. Activity differences are explained on the basis of textural, chemical and structural characteristics of the catalysts as a function of variations in the mentioned preparation parameters, with optimum properties being achieved for the specimen calcined under air at 500 degrees C. (C) 2010 Elsevier B.V. All rights reserved.