High-Temperature Oxygen Sorption in a Fixed Bed Packed with Perovskite-Type Ceramic Sorbents

Abstract

Oxygen sorption and desorption on two perovskite-type ceramics, La0.1Sr0.9Co0.5Fe0.5O3-δ and La0.1Sr0.9Co0.9Fe0.1O3-δ, were studied in a fixed-bed system. The perovskite-type ceramic packed fixed bed gives very sharp oxygen sorption breakthrough curves with long breakthrough time in the range of 400−900 °C as a result of a favorable oxygen sorption isotherm, high oxygen sorption capacity, and fast oxygen sorption rate for the sorbents. The perovskite-type ceramic sorbents can be reversibly regenerated and exhibit good structural and chemical stability against sorption and regeneration cycles. These results suggest that the perovskite-type ceramic sorbents can be used in fixed-bed processes for effective removal of oxygen from gas streams using a reducing gas sorbent regeneration. The perovskite-type ceramic sorbents can also adsorb a considerable amount of oxygen in 200−300 °C but at a much slower rate. The desorption breakthrough curves are characterized by long tails due to slower desorption rate consta...