The Influence of Hydrothermal Temperature on CaO-based Adsorbents Synthesized by Sol-Gel-Hydrothermal Method

To capture carbon dioxide (CO2), a major green house gas from flue gas, several kinds of adsorbents have been synthesized, characterized and tested. In this study, CaO-based adsorbents were synthesized via sol-gel-hydrothermal method and different hydrothermal temperatures (100, 120, 140 and 160 °C) have been investigated in order to verify their influence on the CaO-based adsorbents. Experimental results showed that the Ca(OH)2 adsorbent with a mixture of CaCO3 synthesized at 120 °C hydrothermal treatment possesses high CO2 adsorption capacity (0.52 g-CO2/g-sorbent) and at 160 °C hydrothermal treatment, CaC2O4.H2O adsorbent was observed and its CO2 adsorption capacity was 0.46 g-CO2/g-sorbent for first carbonation/calcination cycle.