Effect of ethanol concentration on CaCO₃phase formation with carbonation method

CaCO3 powder in the form of PCC is needed in various industrial fields. The formation of the CaCO3 phase is influenced by the reaction medium. Ethanol is used as a reaction medium because it has a lower surface tension coefficient than water. The surface tension coefficient is related to the energy of crystal formation. In this study, Ca(OH)2 solution was mixed with ethanol with a volume ratio of 30% and 50% with a stirring rate of 200 rpm at room temperature. The carbonation method is carried out with a CO2 gas flow rate of 2.35 lt/min. The results of observations with XRD and SEM showed the formation of calcite, vaterite and aragonite phases. The addition of 30% ethanol into the reaction medium for 5 hours and immersion for 3 days increased the vaterite phase by 53.57% and the aragonite phase by 4%. Meanwhile, the addition of 50% ethanol decreased the vaterite phase by 69.77% and increased the aragonite phase by 375%.