(Special session) Recent trends in the development and utilization of coal and other energy resources

[3101-07-03] The efficiency of carbonation on CO₂ mineralization with fly ash and seawater

○Theodora Noely Tambaria¹, Yuichi Sugai¹, Takehiro Esaki¹ (1. Kyushu University)

Chairperson：菅井 裕一（九州大学）

Keywords:CO2 mineralization, Fly ash, Seawater, Carbonation efficiency, pH

Direct carbon dioxide (CO₂) mineralization utilizing fly ash represents a promising technology for achieving CO₂ sequestration. Given its abundance and calcium-rich composition, we are currently exploring seawater's potential as a viable alternative for CO₂ sequestration. Despite limited prior research and an unclear mineralization mechanism, we are employing fly ash with seawater to conduct direct CO₂ mineralization under ambient conditions to assess carbonation efficiency. Our findings have uncovered a critical pH range (8-10) that enhances calcium elution efficiency, amplifying carbonation efficiency. Within this pH range, magnesium hydroxide (Mg(OH)₂) significantly influences calcium carbonate (CaCO₃) precipitation kinetics and crystalline phase. This innovative approach holds promise for carbon sequestration and has the potential to substantially contribute to sustainable CO₂ utilization strategies, addressing the urgent need in our current environmental context.