Novel Regenerable Sodium-Based Sorbents for CO2 Capture at Warm Gas Temperatures

A novel sorbent consisting of NaOH/CaO was developed for CO 2 capture at 315 °C suitable for high-temperature CO 2 -capture applications, such as coal gasification systems. The sorbent is regenerable at 700 °C, and steam does not affect the sorbent performance. A multicycle test conducted in the atmospheric reactor at 315 °C indicated that the sorbent improved the performance with an increased number of cycles. The sorbent can also capture CO 2 at a wide range of temperatures from ambient to 500 °C. However, the mechanism of CO 2 capture is different at ambient temperature. The sorbent is unique because it has a high CO 2 -capture capacity of more than 3 mol/kg at 315 °C and is regenerable at 700 °C.