Calcium Ion Extraction from Blast Furnace Slags for the Synthesis of Pure Calcium Carbonate Polymorphs by Accelerated Carbonation

This study investigates a possibility of synthesizing calcium carbonate following the process of extracting calcium ion (Ca) from air-cooled blast furnace slag by using pure CO2 gas at various pressures and extraction agents. At first, Ca ion Source from air-cooled blast furnace slag was firstly extracted at CO2 pressure and using acids and ammonium solutions. And then, we compared extraction rate CO2 pressure and various solutions. Finally, we performed calcium carbonate synthesis using aqueous CO2 and extracted Ca ion by the CO2 pressure, acetic acid. Following the process, calcium carbonate was effectively synthesized by the reaction between extracted Ca and CO3, a form of dissolved CO2. We expect that this study could demonstrate a possibility of conversing the slag and CO2 from the steel industry into high value added product, Calcium carbonate.