Magnesium industry waste and red mud to eco-friendly ternary binder: Producing more sustainable cementitious materials

The increasing demand for cement-based materials has led to significant energy expenditure and greenhouse gas emissions. To produce more sustainable cementitious materials, partial Portland cement (PC) substitution is proposed, reducing clinker consumption and mitigating negative environmental impacts. Magnesium and aluminum industries produce tons of waste annually, including magnesium industry waste (MW) and red mud (RM). This study evaluated the feasibility of using industrial waste (i.e., MW and RM) as supplementary cementitious materials. A PC/MW/RM mixture containing 75% PC substituted with 25% of MW and RM (20% + 5%, 5% + 20%, and 12.5% + 12.5%) was developed as a ternary binder. Physical-chemical properties, such as phases, oxide composition, particle distribution and morphology, thermal behavior, and pozzolanic potential, were identified for the residues; the compressive strength of the prepared mortars was compatible with current standards. Therefore, partial substitution of PC with residues is feasible for producing eco-friendly binders.