Abstract: The use of a cementitious composition is described, as a coating for disposable foundry cores, said cementitious composition comprising at least one binder or hydraulic cement in a quantity ranging from 40% to 99.9% by weight with respect to the total weight of the cementitious composition; possibly one or more fillers in a quantity ranging from 0.1% to 60% by weight, with respect to the total weight of the cementitious composition, said filler preferably having a D99<100 ?m; at least one rheology modifying agent selected from cellulose, derivatives of cellulose such as methylhydroxyethylcellulose, vinyl acetate/versatate copolymers, polycarboxylate ether polymer, or a mixture thereof, in a quantity ranging from 0.1% to 5% by weight with respect to the total weight of the cementitious composition. A disposable foundry core is also described, having at least one coating layer based on said cementitious composition.

Abstract: The present invention describes the preparation of nanotubes made from portlandite, the naturally occurring form of calcium hydroxide, Ca(OH)2. Portlandite nanotubes are obtained by a process comprising the following steps: a) reacting calcium chloride with calcium oxide in aqueous solution, thus obtaining an aqueous dispersion; b) feeding as such the aqueous dispersion obtained in step a) to a hydrothermal reaction, thus obtaining portlandite nanotubes. The invention also concerns the use of the portlandite nanotubes as a component for cementitious compositions to provide reinforced mortar or concrete.

Abstract: New photocatalytic product comprising compounds of titanium integrated with limestone. The product is obtained by reacting limestone with a suitable precursor of titanium dioxide in a basic solution, followed by accurately washing the solid obtained, drying it and calcining it. A composite is obtained containing limestone, titanium dioxide and calcium titanate. The composite thus obtained, used as such or in mixture with other components, has shown an unexpectedly high photocatalytic activity.

Abstract: New photocatalytic product comprising compounds of titanium integrated with limestone. The product is obtained by reacting limestone with a suitable precursor of titanium dioxide in a basic solution, recovering the product in particular conditions, drying it and calcining it. By operating in presence of sodium, a composite is obtained substantially free from titanium dioxide, containing limestone and calcium titanate. The composite thus obtained, used as such or in mixture with other components, has shown an unexpectedly high photocatalytic activity.

Abstract: The invention relates to a sulfo-aluminous clinker with optimal setting time and short term compressive strengths, comprising a mixture of the following phases: —calcium sulfoaluminate, or C4A3$, in amounts higher than 50% by weight of the mixture, —belite, or C25, in amounts between 2 and 23%, —3C25 3C$ CaX2, X being fluorine or chlorine, between 3 and 15% —C11A7CaX2, X being fluorine or chlorine, between 2 and 12%, both fluorine and chlorine being altogether present in the mixture, and phase C5S2$ being absent. The invention also relates to a method for preparing this sulfo-aluminous clinker, and hydraulic binders comprising this clinker.

Abstract: The invention relates to a sulfo-aluminous clinker with optimal setting time and short term compressive strengths, comprising a mixture of the following phases: calcium sulfoaluminate, or C4A3$, in amounts higher than 50% by weight of the mixture, belite, or C2S, in amounts between 2 and 23%, 3C2S 3C$ CaX2, X being fluorine or chlorine, between 3 and 15% C11A7CaX2, X being fluorine or chlorine, between 2 and 12%, both fluorine and chlorine being altogether present in the mixture, and phase C5S2$ being absent. The invention also relates to a method for preparing this sulfo-aluminous clinker, and hydraulic binders comprising this clinker.

Abstract: New photocatalytic product comprising compounds of titanium integrated with limestone. The product is obtained by reacting limestone with a suitable precursor of titanium dioxide in a basic solution, recovering the product in particular conditions, drying it and calcining it. By operating in presence of sodium, a composite is obtained substantially free from titanium dioxide, containing limestone and calcium titanate. The composite thus obtained, used as such or in mixture with other components, has shown an unexpectedly high photocatalytic activity.