This paper presents a novel system for production of pure oxygen based on the integration of a solid oxide fuel cell (SOFC) and a solid oxide electrolyzer (SOEC). in the proposed arrangement, the SOFC provides electricity, heat and H2O in vapour phase to the SOEC which carries out the inverse reactions of the SOFC, that is the separation of H2O into H-2 (used as a fuel for the SCFC) and 02 (representing the yield of the system). Simulations carried out in different operating conditions show that when the integrated SOFC-SOEC device runs at low current densities (less than 1000A m(-2)), pure oxygen can be generated with an electric consumption comparable to mid-size cryogenic air separation units, and significantly lower than small scale systems based on the PSA technology. (C) 2009 Elsevier B.V. All rights reserved.