Citrate route to prepare K-doped Li2ZrO3 sorbents with excellent CO2 capture properties

K-doped Li2ZrO3 sorbents with excellent CO2 capture properties were synthesized via a citrate route. The CO2 capture–regeneration properties of these synthesized K-doped Li2ZrO3 sorbents were investigated by thermogravimetric analysis (TGA) at different temperatures and CO2 partial pressures. The synthesized K-doped Li2ZrO3 sorbents possess a better CO2 capture performance than reported Li2ZrO3-based ones, especially at low CO2 partial pressures. At 823 K and a CO2 partial pressure of 0.25 bar, the uptake of CO2 in the K-doped Li2ZrO3 with an optimized K:Li:Zr composition of 0.2:1.6:1 in molar ratio can reach 23 wt.% within 15 min. Furthermore, the sorbent displays a good stability, confirmed by CO2 capture–regeneration cycles.

Graphical abstractK-doped Li2ZrO3 sorbents synthesized via a citrate route exhibit a better CO2 capture performance than reported sorbents, including a faster uptake and a higher, nearly stoichiometric absorption capacity at low CO2 partial pressures.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► K-doped Li2ZrO3 sorbents were synthesized via a citrate route. ► The sorbents exhibit a better CO2 capture performance than reported sorbents. ► The sorbents could be applied in CO2 capture at high temperatures in practice.