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Oxygen sorption/desorption properties of SrCo x Fe1-x O3−δ were examined as an oxygen sorbent for a high-temperature pressure-swing adsorption (HT-PSA) process. Perovskite-type structure of the SrCo x Fe1-x O3−δ powder samples was observed in the composition range of 0 ≤ x ≤ 0.85, by using XRD measurements. A temperature-programmed-desorption (TPD) measurement revealed that the oxygen desorption temperature in N2 for the perovskite-type SrCo x Fe1-x O3−δ samples was lowered with increasing x. Consequently, the oxygen desorption temperature of the SrCo0.85Fe0.15O3−δ sample exhibited around 300 °C, which was the lowest of those of the examined samples. A high-temperature X-ray diffraction (HT-XRD) measurement suggested that the oxygen desorption of SrCo0.85Fe0.15O3−δ in N2 occurred, accompanying the phase transition from perovskite-type structure to brownmillerite structure. Isothermal oxygen sorption/desorption behavior of the SrCo x Fe1-x O3−δ samples was examined by means of thermogravimetric analysis (TGA). As a result, it was confirmed that the amount of sorbed oxygen for the SrCo0.85Fe0.15O3−δ sample gave 11.7 cm³ g-1 at 300 °C, which was larger than that (8.6 cm³ g-1) for a benchmark oxygen sorbent (La0.1Sr0.9Co0.9Fe0.1O3−δ). In order to obtain oxygen-enriched air by using the SrCo0.85Fe0.15O3−δ pellet sample as the oxygen sorbent, the oxygen separation from synthetic air was carried out by using a small-scale PSA apparatus equipped with a vacuum pump. It was confirmed that the 45 vol % oxygen-enriched air was obtained even at 300 °C, by using this apparatus. [ABSTRACT FROM AUTHOR]