Lithium carbonate-metal oxide mixtures and its application for a CO 2 absorbent

Abstract

Reactivity of the mixed powder of Li2CO3 with several metal oxides (Y2O3, Al2O3, ZrO 2, SiO2 and ZrSiO4) in synthetic air and 100%CO2 was examined to develop a high temperature repeatable CO 2 absorbent. The mixture of Li2CO3 and Y 2O3 in molar ratio of 1: 1 was stable in CO2 up to 950°C but decomposed to form LiYO2 at around 850°C in synthetic air (N2 79% + O2 21%, CO2 <0.5 ppm). The newly formed LiYO2 started to absorb the CO2 at 300°C with the reaction of 2LiYO2 + CO2→Li 2CO3 + Y2O3. Since the mixture was fairly stable in CO2 up to 980°C, the reversed reaction directed to CO2 emission was not observed in CO2. LiYO2 is a new material for a CO2 absorbent available in a wide range of temperature.