Abstract:
The CeO
2-doped CaO-based sorbent was prepared by the homogeneous precipitation method using P123 as the soft template. The influence of CeO
2 doping on the capture of CO
2 was investigated. The CeO
2 doping can promote the formation of surface oxygen species, and facilitate the carbonation reaction. The interactions in CaO-CeO
2 lead to the electrons transfer from Ca to surface oxygen species. Moreover, when Ce ions are substituted by Ca ions, the charge neutrality is destroyed in the CeO
2 crystal, which promotes the formation of oxygen vacancies and O
2-.
Ea is tested to be 28.1 kJ/mol for the carbonation reaction of pure CaO sorbent, while
Ea decreases to the minimal value of 10.2 kJ/mol when adding CeO
2 to CaO sorbent with a Ce/Ca molar ratio of 0.25. Also, the doping of CeO
2 is beneficial to the high dispersion of CaO and prevention of CaO sintering. The Ce-doped sorbents exhibit a superior capture capacity and cyclic stability in carbonation/calcination cycles.