Resource utilization of lithium slag supplementary cementitious materials through mechanical activation: mechanism...

The use of lithium slag (LS) in the preparation of supplementary cementitious materials (SCM) effectively mitigates the environmental pollution caused by open-air storage and landfill disposal of LS. Focusing on region-specific LS as the subject of study, this research proposes optimizing the mechanical properties of SCMs by regulating the grinding time and LS dosage. Based on the analysis of the hydration products and microstructure of the SCM, the LS with the median particle size of 11.71 μm demonstrated the highest activity index, achieving a 28-day compressive strength of 107 % compared to ordinary Portland cement. Remarkably, the 3-day strength also exceeded that of pure cement, likely due to the dilution effect of LS, which provides additional nucleation sites for hydration products like C-S-H and AFt. With 30 % LS replacing cement, the compressive strength of SCM reached 54.61 MPa, comparable to that of pure cement. The introduction of LS significantly reduced the interparticle pore volume. These findings provided a scientific basis for promoting the resource utilization of LS waste and its application in SCM production.