Cost-Effective and Green Additives of Pozzolanic Material Derived from The Waste of Alum Sludge for Successful Replacement of Portland Cement

Abstract The primary purpose of this investigation was to find out whether it would be feasible to successfully replace Ordinary Portland Cement (OPC) with 5, 10, or 15 mass % of activated alum sludge waste (AAS) as a pozzolanic material. This was the overarching question that guided the research that was conducted. A study into the use of low-cost nanocomposites to increase the physical, mechanical, and stability against the fire of OPC–AAS-hardened composites was carried out. The goal of this inquiry was to explore the utilization of low-cost nanocomposite. Producing CuFe2O4 spinel nanoparticles with an average particle size of less than 50 nm was doable. The introduction of CuFe2O4 spinel into a variety of OPC–AAS-hardened composites improve both the physicomechanical characteristics of the composites at nearly typical curing ages as well as the resistance of the composites to the effects of fire. Techniques such as TGA/DTG and XRD were utilized to provide evidence that synthesized CuFe2O4 spinel had favorable properties. These approaches revealed the presence of a range of hydration yields, such as CSHs, CASHs, CFSHs, and CuSHs, which improve the overall physicomechanical parameters as well as the thermal stability of a wide variety of OPC–AAS-hardened composites. The composite material that is composed of (90 % OPC, 10 % AAS waste, and 2 % CuFe2O4 offer several advantages, both financially and ecologically.