The present invention discloses a method of manufacturing micronized sandstone obtained from ceramics or industrial wastes of ceramic manufacturing, such as white paste, natural stones or clinker, including TiO.sub.2 as bio-additive, and product obtained by the micronized sandstone thereof. The ceramics and industrial wastes of ceramic are grinded in several steps and the resultant powders are collected by means of individual filters and further combined in a nanopowder micronizer for posterior treatment, where TiO.sub.2 hydrolyzed can be optionally added. This micronized sandstone comprising the bio-additive TiO.sub.2 is used in the production of plasters, mortars, grouts and/or as additive for paints and/or epoxy enriched with TiO.sub.2. The micronized sandstone bio-additive with TiO.sub.2 can be additionally subjected to two optional embodiments of the invention: treatment with or without the use of a pigment. In order to obtain the final product that can be used in the production of blocks, floors and other products of various sizes, an agglomerating agent combined with TiO.sub.2 is added to the micronized sandstone comprising the bio-additive TiO.sub.2, either in an aqueous solution or as a dry product, optionally including colored oxides.

A method for producing photocatalytic mortar includes providing a mortar-producing material including a fine aggregate and cement, a reactant mixture including a zinc source and urea, and a microorganism-containing mixture including water and a urease-producing microorganism, subjecting the microorganism-containing mixture and the reactant mixture to microbial induced precipitation in the mortar-producing material, subjecting zinc carbonate crystal-containing mortar produced to curing for the same to undergo hydration, and subjecting cured mortar to hydrothermal synthesis, so that zinc carbonate crystals therein are converted to nano zinc oxide crystals.

A visible-light-photocatalyzed composite light-transmitting concrete contains several bundles of optical fibers, the optical fibers are coated with a protective layer on their outer surface, the protective layer contains a visible light photocatalyst, and the concrete has several gas-permeable pores. Such concrete is prepared by mixing a visible light photocatalyst and a light-transmitting glue, applying the mixture to the surface of optical fibers to form a protective layer, and using optical fibers in the concrete. The resulting concrete has dual properties of light transmittance and photocatalytic oxidation of gas-phase pollutants under visible light irradiation. The visible-light-photocatalyzed composite light-transmitting concrete significantly breaks through the limitation of photocatalytic concrete to light sources, so that gas-phase pollutants can be removed under visible light irradiation through photocatalysis of light-transmitting concrete. It also has good mechanical properties, decorativeness, and functional practicability due to coated optical fibers.

The invention relates to an aerogel concrete mixture containing a photocatalyst, a photocatalytically active high-performance aerogel concrete obtainable therefrom and a method for producing same.

A method of applying a NOx degrading composition on a concrete element, including providing a concrete element having a surface, and applying a composition including photocatalytic titanium dioxide particles dispersed in a continuous phase on the surface of said concrete element. Also, a concrete element having NOx degrading properties. Also, a concrete element having photocatalytic titanium dioxide particles dispersed thereon.

Methods for embedding photocatalytic titanium dioxide in concrete surfaces to reduce pollutants via photocatalytic reactions are provided herein. One method includes mixing a solvent compound with an anatase titanium dioxide (TiO.sub.2) photocatalyst, applying an amount of concrete treatment compound to an upper surface of the concrete, the concrete treatment compound comprising a mixture of a liquid carrier compound with the anatase titanium dioxide (TiO.sub.2) photocatalyst.

Disclosed embodiments concern a composition comprising a diatom frustule and two or more photocatalytic nanoparticles dispersed on the surface of the frustule. Also disclosed are embodiments of a method for making the composition. The nanoparticles are dispersed such that they are separate and not in physical contact with each other. An average distance between the nanoparticles may be from greater than 0 nm to 100 nm. The nanoparticles may comprise a dopant material. Paint compositions comprising the diatom frustule compositions are also contemplated. The diatom frustule composition may be useful for removing and/or degrading volatile organic compounds, such as those present in the atmosphere.

In one aspect, the present invention is directed to a coating composition. The coating composition comprises photocatalytic particles and an alkali metal silicate binder comprising an alkoxysilane. In another aspect, the present invention is directed to a coated article. The coated article has a photocatalytic coating with improved durability on its external surface that is formed from the aforesaid coating composition.

A visible-light-photocatalyzed composite light-transmitting concrete contains several bundles of optical fibers, the optical fibers are coated with a protective layer on their outer surface, the protective layer contains a visible light photocatalyst, and the concrete has several gas-permeable pores. Such concrete is prepared by mixing a visible light photocatalyst and a light-transmitting glue, applying the mixture to the surface of optical fibers to form a protective layer, and using optical fibers in the concrete. The resulting concrete has dual properties of light transmittance and photocatalytic oxidation of gas-phase pollutants under visible light irradiation. The visible-light-photocatalyzed composite light-transmitting concrete significantly breaks through the limitation of photocatalytic concrete to light sources, so that gas-phase pollutants can be removed under visible light irradiation through photocatalysis of light-transmitting concrete. It also has good mechanical properties, decorativeness, and functional practicability due to coated optical fibers.

Process for the preparation of an additive comprising TiO.sub.2 particles dispersed on a support of pseudo-layered phyllosilicate-type, comprising the dispersion in water of the support, the acid activation of the support and the high-shear dispersion of the support with the TiO.sub.2 particles Use of the particles obtained by this process as additives with photocatalytic activity for water purification and disinfection, for purification of polluted gas streams and to provide materials, in particular construction materials, with self-cleaning, biocide, deodorization and/or pollution reduction properties in the presence of air and ultraviolet light.