The present invention relates to a modified red sludge or a modified bauxite residue and processes for producing same, and to a storage medium comprising a modified red sludge, a heat store comprising a storage medium and numerous uses of a It modified red sludge as storage medium, more particularly in a heat store system. The modified red sludge here contains the following components: haematite (Fe.sub.2O.sub.3), corundum (Al.sub.2O.sub.3), rutile (TiO.sub.2) and/or anatase (TiO.sub.2), quartz (SiO.sub.2), optionally perovskite (CaTiO.sub.3) and optionally pseudobrookite ((Fe.sup.3+, Fe2+).sub.2(Ti, Fe.sup.3+)O.sub.5) and/or nepheline ((Na,K)[AlSiO.sub.4]). A novel material is thus provided, and production thereof is described for use as storage medium in a sensitive energy storage system in the low-, medium- or high-temperature sector.

The present invention relates to a modified red sludge or a modified bauxite residue and processes for producing same, and to a storage medium comprising a modified red sludge, a heat store comprising a storage medium and numerous uses of a It modified red sludge as storage medium, more particularly in a heat store system. The modified red sludge here contains the following components: haematite (Fe.sub.2O.sub.3), corundum (Al.sub.2O.sub.3), rutile (TiO.sub.2) and/or anatase (TiO.sub.2), quartz (SiO.sub.2), optionally perovskite (CaTiO.sub.3) and optionally pseudobrookite ((Fe.sup.3+, Fe2+).sub.2(Ti, Fe.sup.3+)O.sub.5) and/or nepheline ((Na,K)[AlSiO.sub.4]). A novel material is thus provided, and production thereof is described for use as storage medium in a sensitive energy storage system in the low-, medium- or high-temperature sector.

Coated inorganic expanding agent particles comprise a core of an inorganic expanding agent and a sol/gel-formed coating comprising a mixed oxide of two or more metals and/or metalloids, in particular a mixed oxide of silicon and at least one metal and/or metalloid selected from aluminum, boron, titanium, zirconium and zinc. The coated inorganic expanding agent particles are added to cementitious systems to avoid shrinkage during hardening. The coating is effective to delay the expanding effect.

Coated inorganic expanding agent particles comprise a core of an inorganic expanding agent and a sol/gel-formed coating comprising a mixed oxide of two or more metals and/or metalloids, in particular a mixed oxide of silicon and at least one metal and/or metalloid selected from aluminum, boron, titanium, zirconium and zinc. The coated inorganic expanding agent particles are added to cementitious systems to avoid shrinkage during hardening. The coating is effective to delay the expanding effect.

Cement-based photocatalytic composition, which comprises: (a) at least one cement binder; (b) at least one photocatalyst; (c) at least one cellulose ether; (d) at least one fluidizing agent; (e) at least one first calcareous filler in the form of particles of which at least 95% by weight has a size not greater than 100 m; (f) at least one second calcareous filler in the form of particles of which at least 95% by weight has a size not greater than 30 m; (g) at least one silane supported on an inorganic support in the form of powder. Such composition can be employed as a water paint for obtaining wall coatings with very low thickness, in particular the outdoor applications, which ensure a high and stable photocatalytic effect over time even with relatively low quantities of photocatalyst, generally lower than 10% by weight, with optimal results in terms of uniformity of the coating and resistance of the same to weathering agents.

Cement-based photocatalytic composition, which comprises: (a) at least one cement binder; (b) at least one photocatalyst; (c) at least one cellulose ether; (d) at least one fluidizing agent; (e) at least one first calcareous filler in the form of particles of which at least 95% by weight has a size not greater than 100 m; (f) at least one second calcareous filler in the form of particles of which at least 95% by weight has a size not greater than 30 m; (g) at least one silane supported on an inorganic support in the form of powder. Such composition can be employed as a water paint for obtaining wall coatings with very low thickness, in particular the outdoor applications, which ensure a high and stable photocatalytic effect over time even with relatively low quantities of photocatalyst, generally lower than 10% by weight, with optimal results in terms of uniformity of the coating and resistance of the same to weathering agents.

The invention relates to a composition which contains modified chromate-deficient red mud, comprising a mineral composition of10 to 50 wt. % of iron compounds,12 to 35 wt. % of aluminum compounds,5 to 17 wt. % of silicon compounds,2 to 10 wt. % of titanium dioxide,0.5 to 6 wt. % of calcium compounds,0 to 1 ppm of chromium (VI) compounds, andoptionally additional unavoidable impurities. The composition, in particular the modified chromate-deficient red mud, contains a poorly soluble reducing agent for Cr(VI). In this manner, an inexpensive chemical composition is provided in particular as an iteratively functioning long-term adsorbent for pollutants in liquid, gaseous, and solid milieu. The invention further relates to a method for producing same and to uses thereof.

The invention relates to a composition which contains modified chromate-deficient red mud, comprising a mineral composition of10 to 50 wt. % of iron compounds,12 to 35 wt. % of aluminum compounds,5 to 17 wt. % of silicon compounds,2 to 10 wt. % of titanium dioxide,0.5 to 6 wt. % of calcium compounds,0 to 1 ppm of chromium (VI) compounds, andoptionally additional unavoidable impurities. The composition, in particular the modified chromate-deficient red mud, contains a poorly soluble reducing agent for Cr(VI). In this manner, an inexpensive chemical composition is provided in particular as an iteratively functioning long-term adsorbent for pollutants in liquid, gaseous, and solid milieu. The invention further relates to a method for producing same and to uses thereof.

A method of delivering polymeric microspheres to protect a cementitious composition, such as concrete, from freeze-thaw damage which comprises the addition of a dry blend of mineral powder and dry-expanded polymeric microspheres to cementitious compositions is described. The polymeric microspheres form annulus voids in the cementitious matrix by undergoing thermal contraction as the ambient temperature drops. The annulus voids act as entrained air voids to provide spaces for ice crystals to grow, thereby greatly reducing or eliminating the risk of cracking of the cementitious composition during freezing and thawing.

A method of delivering polymeric microspheres to protect a cementitious composition, such as concrete, from freeze-thaw damage which comprises the addition of a dry blend of mineral powder and dry-expanded polymeric microspheres to cementitious compositions is described. The polymeric microspheres form annulus voids in the cementitious matrix by undergoing thermal contraction as the ambient temperature drops. The annulus voids act as entrained air voids to provide spaces for ice crystals to grow, thereby greatly reducing or eliminating the risk of cracking of the cementitious composition during freezing and thawing.