High redox performance of Y0.5Ba0.5CoO3−δ for thermochemical oxygen production and separation

Abstract

The efficient production and separation of oxygen is essential for numerous energy-intensive industrial applications in the fuel and mineral processing sectors. A thermochemical redox cycle is considered for separating oxygen from atmospheric air and other gas mixtures using solar or waste process heat. Based on electronic structure (DFT) computations Y_0.5Ba_0.5CoO_3−δ is selected as a redox material, which surpasses the redox performance of state-of-the-art Cu₂O. The thermochemical oxygen production is experimentally demonstrated by applying a temperature/pressure swing between 573 K at 0.2 bar O₂ and 873 K at 1 bar O₂. An energy balance shows the feasibility of using process waste heat from the solar thermochemical CO₂/H₂O splitting cycle and the potential to compete vis-a-vis with cryogenic distillation. Exploratory runs with a packed-bed reactor indicate the potential of both thermochemical oxygen production and separation for scale-up and industrial implementation.