The sol-gel synthesized powder was a single phase Li
2ZrO
3. This synthesized powder reacted with CO
2 at temperatures from the ambient temperature to a high temperature. The reaction products reacted reversibly to form Li
2ZrO
3 at temperatures above 925 K. The degree of absorption was defined as the value obtained by dividing the fractional mass gain of Li
2ZrO
3 after absorption by the fractional mass gain corresponding to a 100% reaction. Consequently, the degree of absorption was determined to be 95.2% under the absorption condition of 773 K and 7.2 ks. When CO
2 absorption at 773 K and release at 993 K were repeated five times to examine the cyclic behavior, the degree of absorption was almost the same as the initial amount. The degree of absorption of commercial powder prepared by a solid-solid reaction of Li
2CO
3 and ZrO
2 was 10.6% under the same absorption condition. The degrees of absorption with the sol-gel synthesized powder were determined to be 26, 31 and 43% under the absorption conditions of 293, 313 and 333 K for an exposure time of 115.2 ks. The absorption behavior could be best explained by an intraparticle diffusion mechanism. The diffusion of CO
2 gas through the reaction product with an apparent activation energy of 24 kJ·mol
−1 was a rate-determining step of the absorption reaction.
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