(474a) Electrospun Ca2CuO3 Fibrous Sorbent for Post-Combustion CO2 Capture

CaO is the well-known sorbent for post-combustion CO₂ capture. High capacity, abundancy and low-cost makes this sorbent attractive. Despite the advantage, it suffers from sintering during carbonation and regeneration process at high temperature. Structural modification can be the key for the stable long-term operation of the sorbent. One of the effective modification methods is incorporation of an inert phase to hinder sintering. We synthesized Ca₂CuO₃ that spontaneously decomposes into CaO and copper under reducing condition. The bulk oxide powder was made by sol-gel synthesis from calcium nitrate, copper acetate, and citric acid complexant. The same strategy was used to make fibrous Ca₂CuO₃ by electrospinning with PVP as the polymeric structure directing agent. In all cases, 900 °C calcination in air removed all organic component and resulted in the targeted oxide phase. Both the bulk powder Ca₂CuO₃ and the fibrous Ca₂CuO₃ were decomposed into CaO and Cu by hydrogen reduction. The endogenous copper phase acts as a sintering barrier for CaO in the calcium looping process. The conversion kinetics and stability of these sorbents were investigated in the carbonation and regeneration process at high temperature. The results were compared to pure CaO of the two different physical forms. We observed higher stability and faster kinetics for the electrospun sample. The faster kinetics is due to high porosity and large specific area of electrospun nanofibers that gives them a unique potential for high catalytic activity. The presence of copper phase enhanced the stability of the sorbent by sintering suppression