https://doi.org/10.1039/C6TA06133H
“Detailed results of the CO2 absorption performance of the sample (eutectic-3) at temperatures of 623–923 K are shown in Fig. 5a. As shown, absorption capacity as high as 35% could be observed at the temperature of 923 K. It should be noted that the amount of CO2 adsorbed was higher than the value expected based on the stoichiometry of the reaction of one CO2 molecule with one orthosilicate available in the eutectic-3 sample (see Fig. 4c and 5a). It is possible that the reaction might have continued till silica is formed (instead of Li2SiO3) at least in some of the fractions of the powder mixture. Further studies are required to fully understand the chemisorption mechanism of these samples.”
“Fig. 5 (a) CO2 absorption curves of the eutectic mixture (eutectic-3) at various temperatures. (b) Absorption rates of eutectic-3 at different temperatures (rate values calculated from the initial two minutes of the absorption curve) in comparison to those of the microwave sol–gel and sol–gel samples. (c) Graph of ln K versus 1/T for the two different processes of chemisorption (K1) and diffusion (K2) observed for the eutectic-3 sample.”
“An enhanced absorption rate was observed at temperatures as low as 623 K. Fig. 5b shows a good comparison of the absorption rates of the eutectic-3 sample with the unmodified microwave and sol–gel26 samples (calculated for the first 2 minutes of absorption). The rate of absorption observed for the eutectic-3 sample, 0.28 wt% s−1 at 923 K, was significantly higher than the absorption rates measured with the unmodified microwave sol–gel and sol–gel samples. A comparison of the reported results (as shown in ESI S1†) including the most recent literature also shows that the absorption performance of the sample is exceptional. The CO2 absorption value of the sample, in fact, reached >30 wt% within the first 42 seconds, based on which the absorption rate could be calculated to be 0.72 wt% s−1.”