Reusing waste toner powder as functional additives for alkali-activated slag

The incorporation of waste toner powder (WTP), a recognized hazardous waste , into cementitious materials as a functional additive offers a cost-effective disposal method and a sustainable utilization approach. This study examines the feasibility of integrating WTP into alkali-activated slag (AAS) compositeswith a focus on the potential of WTP to enhance the material properties of these composites. Microstructural analysis using SEM confirmed that the inclusion of a dispersing agent (PCE) improved the dispersion of WTP, minimizing particle agglomeration . Rheological tests indicated that increasing WTP content reduced flowability and increased plastic viscosity , though PCE pretreatment helped mitigate these effects. Compressive strength results showed a reduction in strength with higher WTP content, likely due to the limited involvement of WTP in the hydration process . Nevertheless, the strength levels remained sufficient for practical applications. Electrical resistivity measurements demonstrated increased conductivity with higher WTP content, indicating potential self-sensing capabilities. Leaching tests revealed that the AAS composite effectively immobilized heavy metals , ensuring safety for landfill disposal . XRD and MIP analyses provided further insights into WTP’s impact on hydration dynamics and pore structure , with PCE enhancing pore refinement. This work introduces a novel valorization strategy for hazardous WTP by developing multifunctional AAS-based composites with potential self-sensing properties. These findings offer practical implications for smart infrastructure development and sustainable waste management in the construction industry.