CO_2 reduction-conversion to precipitates and morphological control through the application of the mineral carbonation mechanism

摘要

This study aimed to verify CO2reduction and morphological control of its precipitates by applying the CO2mineralization mechanism under ambient conditions. In the first stage, CO2absorption-conversion experiments were performed using three types of amines (mono-ethanolamine, MEA; di-ethanolamine, DEA; and methyl-di-ethanolamine, MDEA) to improve the rate and efficiency of CO2conversion into metal carbonates. In the second stage, CO2was re-absorbed and supplied as aqueous CO2, forming MgCO3and MgCO3(H2O)3precipitates. The formed MgCO3was analyzed by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). In particular, MgCO3was formed only in the MEA solution although other amines were exposed to the same experimental conditions. Therefore, the results showed that the CO2precipitate morphology could be controlled by the type of the conversion solution used. This study has significance regarding CO2reduction and utilization because the emitted CO2could be stored semi-permanently. Furthermore, the formed MgCO3could be re-used in various industries through morphology control. Therefore, this study verified the potential of the CO2mineralization mechanism for CO2reduction and morphology control.