The steam gasification of biomass in the presence of calcium oxide offers a viable route for the dual purpose of hydrogen production and carbon dioxide (CO 2 ) capture. Although previous studies have dealt with experimental and intrinsic rate constants of carbonation and calcination of calcium looping cycles, the data has not been compared with thermodynamic or kinetic simulation. In this study, the thermodynamic and kinetic simulation of the CO 2 capture process using two calcium-based sorbents (i.e., Imasco dolomite and Cadomin limestone) have been studied using Aspen Plus software. The thermodynamic simulation was able to predict the overall trend of the CO 2 adsorption on dolomite and limestone. However, a kinetic model was also applied to achieve a more accurate analysis. The results show good agreement between the modeling and the experimental data obtained using a thermogravimetric analyzer (TGA). A shift in the reaction mechanism was observed with respect to temperature. The experimental data and kinetic model illustrated that the maximum conversion occurred at 650 °C.
In this study, a series of core-shell structured spheriform CO 2 sorbents were synthesized by using CaO-based pellets as cores and different mesoporous metal oxides (e.g. alumina, ceria, and yttrium-stabilized zirconia) as shells through a repeated wet impregnation coating process. Cyclic CO 2 capture performance of the obtained sorbents was investigated using a thermogravimetric analyzer. Among all the core/shell sorbents under study, the pellets coated with a layer of alumina exhibit the best performance in the retention of CO 2 uptake over 20 cycles with the lowest activity loss of only 30.4 %, attributed to the existence of the thermal stable porous alumina shell which prevents the sintering and the aggregation of the CaO grains. Moreover, the attrition study using an air-jet apparatus and a standard test method reveals that such sorbents exhibit enhanced attrition resistance due to the protection of the porous shell providing them with a great potential for application in fluidized bed conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.