鉱山廃棄物による炭素貯留の可能性を示す研究（Mining waste product could help store carbon emissions, study suggests）

2026-04-17 コンコルディア大学

＜関連情報＞

• https://www.concordia.ca/cunews/encs/2026/04/17/mining-waste-product-could-help-store-carbon-emissions-concordia-led-study-suggests.html
• https://www.sciencedirect.com/science/article/pii/S1385894726023624

鉄分を多く含むスラグ材料による炭素隔離の評価 Evaluation of carbon sequestration by iron-rich slag materials

Samantha M. Wilcox, Catherine N. Mulligan, Carmen Mihaela Neculita

Chemical Engineering Journal  Available online: 4 March 2026

DOI:https://doi.org/10.1016/j.cej.2026.174903

Graphical abstract

Highlights

• CO₂ capture by titanium slag achieved up to 99.5% CO₂ removal
• CO₂ trapping achieved was up to 98.5% in the solid phase primarily via adsorption
• Mineral trapping was as CaCO₃ and Fe₆(OH)₁₂CO₃H₂O
• Liquid phase CO₂ removal was via solubility and mineral trapping

Abstract

Mining and metalliferous alkaline waste offer an opportunity for carbon sequestration by trapping carbon dioxide (CO₂) through hydration, sorption, or precipitation. The objective of this paper was to determine the feasibility of two iron-rich slag materials for use as a substrate to sequester injected CO₂. The physical, chemical and mineralogical characteristics of both samples were analyzed showing a larger particle size, smaller surface roughness, and higher porosity for S2 than S1. Both samples were injected with 10% v/v CO₂ in airtight media bottles that were agitated for 24 h with various initial moisture conditions. Both wastes exhibited high potential for carbon trapping with up to 92.5% and 99.5% CO₂ removal for samples S1 and S2, respectively. Through qualitative and quantitative analysis, results showed that both samples showed precipitates of minor carbonate phases. S1 precipitated calcium carbonate (CaCO₃) and S2 precipitated CaCO₃, magnesite (MgCO₃), and siderite (FeCO₃) achieving mineral trapping. However, the majority of solid phase CO₂ removal was attributed to chemical adsorption onto the metal-based surfaces of iron-rich slag materials. At 10% (v/v) CO₂, solid phase CO₂ trapping has the potential to remove 1000 and 1073 g CO₂ per tonne of S1 and S2, respectively. The results are promising for carbon trapping using metalliferous waste at low moisture conditions.