Study to improve the reactivity of magnesium cations to CO₂ for carbon capture and utilization technology using edible salt manufacturing plant wastewater

This study aims to improve the formation of MgCO₃ via inorganic carbon capture utilization (CCU) technology using industrial wastewater from an edible salt manufacturing plant. Wastewater contains concentrated Mg²⁺, which can be used in various industries. Despite its possible applications and advantages, Mg²⁺ is not typically used in inorganic CCU technology because its chemical properties make it difficult to convert it into metal carbonate. The formation of magnesium carbonate from wastewater is a challenge because the mechanism of magnesium carbonate formation is not well understood, especially the influence of the other cation components. To determine the influence of the other cation components, we designed eight simulated wastewater samples consisting of different cation components and concentrations: Mg²⁺, Mg²⁺ with Ca²⁺, Mg²⁺ with Na⁺, Mg²⁺with Ca²⁺, and Na⁺. By comparing their results, we demonstrated the influence of other cations on magnesium carbonate formation. These results indicate that Ca²⁺ should be removed from the reactant to form magnesium carbonate. Furthermore, we found that Na⁺ promoted the formation of magnesium carbonate.