CO₂ Absorption and Desorption Abilities of Li₂O–TiO₂ Compounds

Abstract

As an initial stage of the creation of a new solid material for carbon dioxide capture and storage (CCS), the behaviors of CO₂ absorption and desorption were investigated in terms of Li₂O–TiO₂ compounds. The Li₄TiO₄ specimen began to absorb CO₂ at 250°C with the formation of Li₂TiO₃ and Li₂CO₃ phases. The absorption rate was significantly enhanced at 710°C by the formation of the Li₂CO₃-based liquid phase. Decomposition of Li₂CO₃ was observed above 960°C in CO₂ atmosphere and above 900°C in Ar-10%CO₂ atmosphere. In the formation of solid Li₂CO₃ after Li₄TiO₄/CO₂ reaction below 700°C, the reaction rate of CO₂ absorption increased with the decreasing diameter of Li₄TiO₄ particles. The area ratio of the Li₄TiO₄ phase decreased and that of the Li₂TiO₃ phase increased in the Li₄TiO₄ sample after repeating the reaction path of CO₂ absorption and desorption.