A Low-Cost Support Derived Steel Slag with Amine Modification for Post-combustion CO2 Capture

To reduce the CO₂ capture cost of solid amine technology, more attention has been paid to the preparation of support materials from solid waste sources. We use basic oxygen furnace steel slag and blast furnace slag as raw materials. To obtain porous support materials, they are treated by acid etching and combined acid-base treatment, respectively. Then modified them using TEPA, finally successfully prepared two types of steel slag-based solid amine materials (BOFS-xTEPA and BFSX-xTEPA). The technologies of XRF, BET and SEM were used to characterize the materials. A homemade static CO₂ adsorption capacity tester was utilized to test the CO₂ adsorption capacity of the composites at 15% CO₂ and 85% air (wet). The optimal CO₂ adsorption capacity was explored by controlling the parameters in the material synthesis process. In terms of mechanism, a rational explanation for the pore formation of the two porous support materials was provided. Finally, the characteristics of the two steel slag-based solid amine preparation routes were analyzed from various perspectives. In comparison with solid amines derived from other solid waste sources, the advantages of this project were elucidated.