Oxygen sorption/desorption kinetics of SrCo0.8Fe0.2O3-δ perovskite adsorbent for high temperature air separation

Perovskites with high selectivity for oxygen are expected to be advantageous for oxygen production by vacuum pressure swing adsorption (VPSA). However, the kinetics of this process has only been investigated by thermogravimetric analysis (TGA) and fixed-bed setups, which cannot simulate the vacuum desorption process. Furthermore, the adsorption and desorption performances at high pressures are rarely discussed. In this study, the perovskite SrCo0.8Fe0.2O3-delta (SCF82) is prepared, and its isotherm and oxygen sorption and desorption kinetics are studied at 400 degrees C using both TGA and a high-pressure adsorption instrument. The high pressure adsorption and desorption performance confirms that VPSA is more suitable for oxygen production than pressure swing adsorption (PSA). The high-pressure adsorption instrument simulates the vacuum desorption process more effectively than TGA. A high vacuum desorption rate was found, indicating that the adsorption rate has a greater influence than the desorption rate when considering perovskite oxide adsorbents for use with VPSA techniques.