A Fundamental Understanding of MgO-based CO₂ Sorbents = A Fundamental Understanding of MgO-based CO₂ Sorbents

다국어 초록 (Multilingual Abstract)

MgO is regarded as the most promising sorbent for intermediate temperature CO₂ capture due to its abundance in basic sites, high stability, and lower energy requirement for regeneration. However, the CO₂ sorption capacity of MgO is significantly hindered by its relatively slow kinetics and tendency to agglomerate after high-temperature regeneration. Recently, MgO-based sorbents promoted by alkali salts and binary or ternary eutectic mixtures have gained much attention for intermediate temperature CO₂ capture due to their improved CO₂ uptake and MgO conversion. However, the chemistry behind this promoting effect of eutectic mixture to MgO-based sorbents still remains unclear. In this work, we successfully carried out the direct observation of the sorption of gaseous CO₂ over molten EM-promoted solid MgO via in situ TEM. We report the feasibility of using commercially available hydrotalcites as stabilizing additives for NaNO₃-promoted MgO sorbents.