Preliminary study on the production of sustainable and compatible inorganic binders from Calabrian calcareous marls

Sustainable and compatible inorganic binders can be considered the precursor of today’s ordinary Portland cements. The advantages provided by natural hydraulic limes, belite cements and natural cements are that hydration and setting processes take place almost simultaneously. A raw material suitable to produce the sustainable inorganic binders may be calcareous marls (75–60% of carbonates and 25–40% of clay), characterized by a burning temperature of 800–1200°C. At this low temperature C2S (dicalcium silicate), the major hydraulic phase formed, is stable. This type of binders is highly indicated for the restoration of historic buildings due to their high compatibility with historic cements: besides, they show a comparable strength with original cement [1]. Furthermore, these calcined calcareous marls can be considered as effective supplementary cementitious materials (SCMs) to be used as partial substitute of clinker in order to produce eco-friendly cements with reduced environmental impact [2].