https://doi.org/10.1016/j.egypro.2017.03.1167
“The effect of absorption temperature on the sorption capacity for 5.32 wt% CaO (solubility limit [22]) in CaCl2
and 15 wt% CaO in eutectic CaF2/CaCl2 is shown in Figure 3 and 4, respectively. The theoretical sorption capacity
is also included in the figures”
“Figure 3. Effect of absorption temperature on the sorption capacity for CO2 capture in a mixture of 5.32 wt% CaO in CaCl2.
(a) Complete absorption process, (b) linear region used for evaluation of reaction kinetics.”
“Figure 4. Effect of absorption temperature on the sorption capacity for CO2 capture in a mixture of 15 wt% CaO in eutectic CaF2/CaCl2.
(a) Complete absorption process, (b) linear region used for evaluation of reaction kinetics.”
“The temperature has opposite effect on the sorption capacity for the two different salt mixtures. For CO2 capture
in 5.32 wt% CaO in CaCl2, an increase in temperature gives lower capacity and slower kinetics
(Figure 3). However, the small difference in the CO2 removal rate could be due to experimental errors. The total
sorption capacities are 2.3 and 2.0g CO2 / 100g sorbent for T = 768°C and T = 800°C, respectively. In the linear
region, the captured fraction of the applied CO2 decreases from 90.7% to 89.2% for the same temperatures.
For CO2 capture in 15 wt% CaO in eutectic CaF2/CaCl2, an increase in temperature gives higher capacity and
faster kinetics (Figure 4). Sorption capacities of 7.9, 8.2, and 8.3g CO2 / 100g sorbent are observed for
T = 677°C, T = 705°C, and T = 730°C, respectively, while the kinetics show that 82.7%, 89.8% and 93.5% of the
applied CO2 is removed for the same temperatures.
An explanation for this behavior could be that the C aO is completely dissolved in CaCl2, while it is present
substantially above the solubility limit in CaF2/CaCl2. This means that when CaO is present in form of a slurry,
more of the active substance is accessible for the applied CO2, giving faster reactions, higher capacities and higher
capture fractions.”