Characterization of the Prepared CaO-Based Sorbents for Hydrogen Production through Ethanol Steam Reforming

Sorbents for CO2 capture based on CaO have been synthesized and tested for sorption-enhanced steam reforming (SESR) via the co-precipitation method. Various stoichiometries of MgO and CeO2 have been utilized along with Cao and an optimum stoichiometry was identified providing the highest capacity and stability over cycling. The as-synthesized sorbents were structurally characterized by means of XRD and SEM. The thermal characterization was obtained via TGA. The porosity of the synthesized samples was measured by the N-2 adsorption and mercury porosimetry. Based on the outcomes of the current work, the sorbents with the highest capacities presented a highly porous structure with a porosity level higher than 65%. The sorbents were tested at high temperatures over repeated cycling (carbonation/decarbonation) to identify the stability of the synthesized sorbents over cycling. The results showed that the stoichiometry of 6:2:1 (CaO, MgO, CeO2) could retain a capacity up to 25 wt% even after 45 cycles.