The use of a Ni-Ag-O catalyst in a one-step reaction to produce ethylene oxide from ethane was investigated. An optimum ethylene oxide yield of 1.2% was obtained with a selectivity of 12.8% at 310 degrees C. The catalyst was characterized through X-ray diffraction, BET surface area, H-2 temperature-programmed reduction, O-2 temperature-programmed desorption and X-ray photoelectron spectroscopy. The results showed that NiO and Ag in the catalyst favored ethane activation and the formation of ethylene oxide, respectively. (C) 2010 Elsevier B.V. All rights reserved.