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Photocatalytic active tiles: a confirmed industrial reality facing a new challenge with LED lighting
No full textEnvironmental purification is a necessary aspect of scientific research to improve human life quality. Semiconductor photocatalysis, in particular TiO2 in the anatase form, was intensively investigated for its application to environmental pollutants degradation. A TiO2 photocatalyst that exhibits high activity for the oxidation of VOCs offers an economically and technically practical means to clean air and water. As secondary organic aerosols SOA represents one of the main PM constituents, the ability to break down its precursors would certainly lead to a reduction of PM concentration in the air. In literature, several studies propose linear correlations between NOx and PM10 values. Consequently, NOx degradation immediately contributes to PM reduction.
New industrially produced photocatalytic porcelaingrés tiles provide very good photocatalytic performance, but also meet standard requirements with respect to hardness, lack of porosity, vitrified surface and durability. In the preparation, a commercial micro-TiO2 was employed to avoid the use of traditional nano-TiO2 and face no drawbacks due to the possible nanorisks of nanopowders.
Unfortunately, TiO2 strongly suffers from the low photocatalytic activity if it is used under visible light and not under UV light. Among the various possible modifications, the surface decoration with metal or metal oxides NPs can be a good strategy to increase the potential of TiO2 in the visible range. A sonochemical method that exploits the use of high-energy ultrasounds is here suggested to obtain this surface decoration. Samples were tested on the photodegradation of NOx, toluene and acetone in gas phase systems, using both UV and LED lamps
Porcelain gres tiles with photocatalytic properties for a better environment
Full text linkPorcelain gres tiles are characterised by their very low water absorption rate of less than 0.5%, and are manufactured under high pressure by dry-pressing fine processed ceramic raw materials with large proportions of quartz, feldspar and other fluxes. Afterwards, the body of these materials is fired at high temperatures (1200 - 1300°C) in a roller kiln. The final material is characterized by lack of porosity, durability, high breaking and wear resistance properties and a complete frost resistance.
In the past decades porcelain gres tiles underwent significant transformations in terms of appearance and size. At the beginning of the industrial productions, porcelain gres tiles were considered as just a technical material characterized by strong resistance to both abrasion and acid attack, almost lack of porosity, but aesthetically not very beautiful. Today thanks to new industrial production methods, both properties and beauty of these materials completely fit the market requests. In particular, the possibility to prepare slabs of large sizes is the new frontier of the building materials.
Beside these noteworthy architectural features, new surface properties have been introduced in the last generation of these materials. The present paper reports the research at the base of a new kind of fired tiles able to carry out a specific antibacterial and self-cleaning action and to reduce polluting molecules thanks to its new photocatalytic properties due to the surface presence of photoactive micro-TiO2
Self-cleaning measurements on tiles manufactured with microsized photoactive TiO2
No full textHeterogeneous photocatalysis is a rapidly developing field in environmental engineering. It has
a great potential to cope with the increasing pollution in the air. The addition of a photocatalyst to ordinary
building materials such as tiles, concrete, paints, creates environmental friendly materials by which air
pollution or pollution of the surface itself can be controlled and diminished. This work reports the results of
the laboratory research, especially carried out towards air purifying action and self-cleaning measurements.
In particular the research was focused on the study of the photocatalytic behavior of industrially prepared
tiles produced starting from commercial micro-sized TiO2. Air purification action has been investigated
through NOx degradation tests. On the contrary, the degradation of pollution at the surface, also called as
self-cleaning action, is verified by the degradation of two different organic dyes: Rhodamine B (red color)
and Metanil yellow (yellow)
Self-cleaning measurements on tiles manufactured with micro-sized photoactive TiO2
No full textHeterogeneous photocatalysis is a rapidly developing field in environmental engineering. It has a great potential to cope with the increasing pollution in the air. The addition of a photocatalyst to ordinary building materials such as tiles, concrete, paints, creates environmental friendly materials by which air pollution or pollution of the surface itself can be controlled and diminished.
This work presents an overview of the principle of photocatalysis, as well as the results of the laboratory research, especially towards air purifying action and self-cleaning measurements. In particular the research is focused on the study of photocatalytic behavior of tiles (named Active) prepared starting from commercial micro-sized TiO2 [Bianchi (2012)].
Air purification action is investigated through NOx degradation tests. On the contrary, the degradation of pollution at the surface, also called as self-cleaning action, is verified by the degradation of both acid oleic (ISO 27448-1 [1]) and three different dyes: Rhodamine B (red color), Methylene blue (blue) and Metanil yellow (yellow)
Ecoactive porcelain gres tiles: a new challenge for environmental sustainability
No full textAt the beginning of the industrial productions, porcelain gres tiles were considered as just a technical material characterized by strong resistance to both abrasion and acid attack, almost lack of porosity, but aesthetically not very beautiful. Today thanks to new industrial production methods, both properties and beauty of these materials completely fit the market requests. In particular, the possibility to prepare slabs of large sizes [1] is the new frontier of building materials.
Slabs are generally manufactured under high pressure by dry-pressing fine processed ceramic raw materials with large proportions of quartz, feldspar, and other fluxes. Afterwards, the body of these materials is fired at very high temperatures (1200–1300°C) in kilns. The final material is thus characterized by lack of porosity, complete water-proofing, durability, hardness, wear resistance properties, and a complete frost resistance. Beside these noteworthy features, new surface properties have been introduced in the last generation of these materials.
The present work deals with the characterization and photocatalytic activity of commercially available tiles, named ActiveTM, prepared with a surface application of a commercial photoactive micro-sized TiO2 [2] stabilized by a sort of inorganic glue (Si-based) heated at 680°C [3].
Industrially prepared tiles were fully characterized (HR-SEM in Fig.1) and the photocatalytic properties of these materials have been verified through depollution and discoloration tests. In details, the pollution degradation of both NOx [4] and VOCs (acetone and acetaldehyde) in the gas phase and two different organic dyes directly put at the tiles surfaces (Rhodamine B and Metanil yellow) have been investigated. Dyes degradation was monitored by Vis-spectrometer equipped with an integrated sphere (OceanOptics, USB4000-VIS-NIR-ES). The color analysis was performed using the CIEXYZ (Fig.2) and CIELAB models.
Moreover ISO 27448-1 self-cleaning test performed by means of contact angle measurement were also shown [5]
Entire photocatalytic tiles (60x60cm) evaluation in NOx degradation in a continuous bench-scale reactor
No full textPigmentary and micrometric commercial TiO2 was successfully deposited on porcelain grès tiles, which were tested on the NOx photodegradation, showing a very good photocatalytic activity; the reactor structure allows to test tiles of size 60x60 cm directly, simulating in a very realistic way their ability to make better air quality. In particular, we show a reproducible way to test material in industrial scale and not just in laboratory scale. The TiO2 powders are commercial and micrometric, regardless of which there are no papers in literature. As well as to demonstrate that micrometric TiO2 can be used in photocatalysis, it is important to underline that it is less dangerous for health than the nano-powders, it is easier to handle and, not less important, it is absolutely cheaper.
Nowadays it is so important to find new strategies to clean the environment and the possibility to reduce the greenhouse gases emissions is increasingly in demand; NOx in particular are strictly monitored all over the world. TiO2 photocatalysis is a promising technique to break down pollutants and it is possible to directly use it on building materials: however, find a serious and reproducible way to test them and confirm their photo-efficiency would be significant. Although a lot of different reactors have already been developed1,2, they work with small samples and the conditions are often very far from the reality. In this work a reactor able to test photocatalytic building materials in large size is presented, working both under artificial and solar light: the porcelain grés tiles was provided by GranitiFiandre, and they are industrially prepared making use of a particular commercial micro-sized TiO2, according with the fact that TiO2 nanoparticles can cause negative health effects3.
First the photo-activity of these building materials has been demonstrated, showing off their real power to degrade nitrogen oxides. No less important, however, is the creation of a system in which is possible to work with samples of tiles with a size of 3600 cm2, coming very close to reality. In particular, we made a comparison of different source of light, working both under UV and solar, and we performed degradation kinetics of different duration, from a few hours to days. Therefore a complete picture of data is proposed, with an accurate description of the phenomenon
Digital printing to ecoactivate porcelain gres large slabs using micro-TiO2 as photocatalyst
No full textIn the present work, we show the preparation of porcelain grés large slabs and the transformation of the traditional ceramic into an ecoactive material: Active clean air & anti-bacterial ceramicTM has been tested and its antibacterial and self-cleaning properties has been confirmed. New industrially produced photocatalytic slabs provide very good photocatalytic performance, but also meet standard requirements with respect to hardness, lack of porosity, vitrified surface, durability: these are key features required of porcelain floor and wall tiles, which best representing innovation in today’s surfaces. A very interesting product of technological progress, which increasingly asks for sophisticated products with beautiful aesthetic effects, is a maxi floor and wall tile system, which combines the traditional qualities of porcelain with the new features of ultra-high performance. At the beginning of the industrial productions, porcelain grés tiles were considered as just a technical material. Today both properties and beauty of these materials completely fit the market requests. In particular, the possibility to prepare slabs of large sizes is the new frontier of building materials. The digital printing was exploited as a new tool to manufacture photocatalytic tiles even of very large size (150x300 cm)
The Impact of building material
No full textExposure to air pollution represents one of the most important health hazard for either mankind and all the ecosystem, pollution that is not present only outdoor but also indoor. Contrary to what is generally assumed, air in several indoor environments is often more polluted than outdoor air. This is because of the many sources of indoor pollution, which include mold and pollen, tobacco smoke, household products and pesticides, and materials usually used in buildings such as formaldehyde and organic compounds in general. Health effects from indoor air pollutants generally occur after long or repeated periods of exposure and they can be severely debilitating or fatal and we have also to consider that, mainly in the urban areas in more developed Countries, population passes most of the time in closed rooms, houses, offices and schools.
There is still uncertainty about the level of concentrations that can produce specific health problems but it is accepted that even low concentrations of some pollutants that are ubiquitous can be very dangerous often causing undesired effects on health from sensory discomfort to serious consequences for physical conditions.
To improve this situation, new class of building materials can be a good tool to play an active role in environment remediation. At the beginning of the industrial productions, porcelain grés tiles were considered as just a technical material, aesthetically not very beautiful. Today thanks to new industrial production methods, both properties and beauty of these materials completely fit the market requests. In particular, the possibility to prepare slabs of large sizes is the new frontier of building materials.
However, it is time to go further the simple sustainable materials and to produce cements and tiles and in general building materials no longer inert but able to ”work” to improve the well-being of people living in those spaces. In fact, besides the noteworthy architectural features, new surface properties can be introduced in the last generation of generating a new class of ecoactive materials. In particular, deposition of TiO2 transforms the traditional ceramic surface into a photocatalytic eco-active material able to reduce polluting molecules present in air and water, to eliminate bacteria and to reduce the surface dirt thanks to the self-cleaning property, but keeping unchanged the standard requirements with respect to hardness, lack of porosity, vitrified surface, durability typical of a porcelain grés tiles
Photocatalytic porcelain gres Tiles with micro-sized TiO2: tests of degradation of dyes in water
No full textSome particular drawbacks due to the industrial use of nano-sized TiO2 (safety, recovery) can be closed with the choice of micro-sized TiO2 in the anatase form as photocatalytic powder. Good photocatalytic performance in the degradation of three organic dyes in water phase were obtained. Furthermore, tests on industrially prepared photocatalytic tiles, having the surface of porcelain tiles hot-coated with micro-sized TiO2, were also performed. The obtained results can represent a good alternative to TiO2 suspensions and pave the way for the fully industrial use of photocatalysis in environmental remediatio
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