A Facile Starch-Assisted Sol–Gel Method to Synthesize K-Doped Li2ZrO3 Sorbents with Excellent CO2 Capture Properties

A facile starch-assisted sol–gel method combined with freeze-drying technique has been developed to synthesize K-doped Li 2 ZrO 3 sorbents. SEM, TEM, and XRD techniques have been applied to characterize the morphology and structure of the synthesized K-doped Li 2 ZrO 3 samples. The CO 2 capture-regeneration properties of the prepared K-doped Li 2 ZrO 3 sample were investigated using thermogravimetric analysis at different CO 2 partial pressures. The K-doped Li 2 ZrO 3 synthesized using the starch-assisted sol–gel method combined with the freeze-drying technique shows excellent CO 2 capture properties. At 823 K and a CO 2 partial pressure of 0.25 bar, the uptake of CO 2 reaches 22 wt% within 20 min, which is approximately 87% of the stoichiometric sorption capacity (25.3 wt%) of CO 2 in the K-doped Li 2 ZrO 3 with a K:Li:Zr composition of 0.2:1.6:1 in molar ratio. Furthermore, the sorbent shows a good stability, confirmed using capture-regeneration cycles.