Environmental photocatalysis of indoors and outdoors with Tio2 une2
Photocatalyst is a general term for photocatalytic photo-semiconductor materials represented by titanium dioxide at nano-scale. Liquid Titanium Dioxide (SOL) dispersed with an average particle size of 8 nm nanoparticles is the best material for the treatment of environmental pollution in INDOORS y OUTDOORS.
This, under the action of light, will produce a photocatalytic reaction similar to photosynthesis, producing a free hydroxyl radical and active oxygen with a strong oxidizing capacity. It has a strong function of photo-oxidation and reduction and can thus oxidize. It decomposes several organic compounds and some inorganic substances and causes the bacterial cell membranes and proteins of the viruses to be destroyed. Kills bacteria and breaks down organic pollutants. It also disrupts the organic pollutants in non-polluting water [H2O] and carbon dioxide [CO2] .Therefore, it has a strong sterilization, deodorization, mold resistance, anti-fouling, self-cleaning, formaldehyde removal strongly 90%, purification of the air and strong catalytic degradation; effectively reducing toxic and harmful gases in the air and can kill a variety of bacteria. It decomposes and damages the toxins released by bacteria or fungi. It also has the functions of deodorization and antifouling. The photocatalyst of nano-titanium dioxide, in contact with carbon dioxide and water, by using oxygen molecules and water in the air, converts the organic matter. It is a substance that does not change by itself. But it promotes chemical reactions. It is theoretically valid for a long period of time and has low maintenance costs.
- Amplitude: the nano-TiO2 photocatalyst effectively degrades 90% formaldehyde, benzene, toluene, xylene, ammonia, VOCs and other pollutants. It has a broad spectrum and high efficiency disinfection performance that can decompose and eliminate toxins released by bacteria or fungi. In general it has a harmful treatment. Sustainability: During the reaction, the nano-titanium dioxide photocatalyst itself does not change or is lost. The pollutants can be purified continuously under the illumination of the light. This favors a lasting and sustained action. Safety: it is not toxic. It is harmless, safe and reliable for the human body. The final reaction products are carbon dioxide, water and other harmless substances, and will not cause secondary contamination. High efficiency: the nano-titanium dioxide photocatalyst uses the inexhaustible solar energy and other light energy to eliminate and purify the diffuse environmental pollutants in a low concentration state. Results can be easily measured.
A. Purification function of the air: It affects harmful organic substances such as formaldehyde, benzene, ammonia, sulfur dioxide, carbon monoxide and oxides of nitrogen: These are reduced to harmless substances. In particular, it has a good effect on the solution of the deterioration of the atmospheric environment, the influence of chemical substances on new construction materials and furniture in the indoor environment.
B. Sterilization function: has a bactericidal effect on Escherichia coli and Staphylococcus aureus. It also breaks down the harmful compounds released by the dead bodies of bacteria during sterilization. Cell membranes that destroy cells with the superoxidative capacity of TIO2 use cytoplasmic loss to cause bacterial death. It coagulates the viral proteins and prints the viral activity, capturing and killing the floating bacteria in the air.
C. Deodorization function: deodorizing effect on cigarette smell, odor of toilet, smell of garbage, body odor of the animal, the smell of mud and the smell of life. Photocatalyst titanium dioxide has a stronger oxidant capacity than ozone anion (O3) and a stronger absorption power than activated carbon.
D. Anti-fouling function: Photocatalyst titanium dioxide will produce ultra-aqueous characteristics by the treated surface of the object. Simply spraying water on the surface of the object will cause dust and dirt to fall. This way, it has a self-cleaning antifouling function for treated surfaces or substrates. The field of application in the titanium dioxide dispersion of the photocatalyst and the market perspectives are very broad, not only for air purification, but also for automotive transport facilities, ceramics, construction materials, food and beverage equipment, medical equipment, household appliances, environmental protection, degradable plastics, water purification processing, daily necessities and other fields.
E. Anti mildew and antibacterial: prevents the formation of mold and algae and prevents the adhesion of the incrustations.
Field of application in exteriores
It is often used in glass for the treatment of self-cleaning, anti-fogging and anti-glare. When we talk about the self-cleaning treatment involves the activation of TiO2 by effect of UV sunlight, rain and humidity. Another area where photo-catalytic technologies can be very useful is in the degradation of pollutants in indoor environments due to the long time that people spend in the industrialized world indoors (offices, factories, shopping centers, housing, etc.). The performance of photo-catalysis in urban applications can be affected by environmental factors such as the intensity of the incident radiation, relative humidity, temperature and wind. But it also depends on other intrinsic factors such as when it is associated with a support cement such as porosity, type and size of aggregates, the method of application, applied quantity and aging. The way in which we use it to apply depends on the place or material that you want the photocatalysis process to take effect. For example: in the factories, it is normally applied at the end of the production line through spraying, coating or printing methods; In the built environment, it is applied by trained and certified applicators using specialized spray equipment.
PHOTOCATALYSIS WATER TREATMENTS
Photocatalysis is recognized as an alternative to solar disinfection. The investigations published in the reference issue reveal a result with great potential to eliminate the microorganisms present in the water. The decontamination of contaminated water by means of solar photocatalysis is currently one of the most successful applications of solar photochemistry.
The possibility of using solar radiation as a primary source of energy gives it significant and significant environmental value; The process is a clear example of sustainable technology. Photocatalysis is a photochemical process that transforms solar energy (in some applications it is possible to use daylight as a resource to stimulate photocatalysis and thus reduce operating costs) in energy. chemistry through the help or implementation of a photocatalyst. The most widely used catalyst is titanium dioxide (TiO2).
Titanium dioxide is not toxic or generates carcinogenic byproducts. Titanium dioxide can crystallize in rutile and anatase form. The photoreaction mechanism begins when Tio2 is illuminated with photons whose energy is equal to or greater than the energy separation between the valence band and the conduction band. In this situation, an absorption of these photons takes place and the creation in the heart of the electron-hollow pair catalyst (e- and h +), which dissociates into free photo-electrons in the conduction band and photo-holes in the Valencia band Simultaneously, an adsorption of reagents takes place and, according to the redox potential (or energy level) of the catalyst, an electron is transferred to an acceptor molecule (Ox1) producing a reduction reaction thereof; At the same time, a photo-hole is transferred to a donor molecule (Red2), which will oxidize.
Each ion formed reacts to form intermediate and final products. The net flow of electrons is zero and the catalyst remains unchanged. The photon excitation of the catalyst appears as the initial step of the activation of the entire catalytic system. This photocatalyst is commonly a semiconductor that, when activated by radiation from the electromagnetic spectrum, generates reactions that are highly oxidant, such reactions destroy water contaminants This disinfection mechanism is based on a physical phenomenon whereby short waves of ultraviolet radiation produce a division between the cell wall and the membrane of microorganisms and viruses, which deteriorates its cell membrane and inhibits its reproduction , and this generates its elimination without causing physicochemical changes that can alter the treated water.
Some successful applications are the treatment of industrial pollutants, such as phenolic compounds from a variety of industries or the degradation of pesticides, which constitute a wide range of chemical products icos extensively used in agriculture. On the other hand, photocatalysis has been used in the treatment of water contaminated with metals of high toxicity, in this sense the photocatalytic process allows the reduction of metallic cations to deposit them on the semiconductor surface, which can later be extracted by mechanical or chemical methods The photocatalysis has been applied with excellent acceptance to the elimination of herbicides, pesticides, phenol and its derivatives, halogenated hydrocarbons, alcohols, organic acids, nitrogen oxides, dyes or pharmacological products. One of the main advantages of using photocatalysis to clean water is its ability to decompose even very low concentrations of substances that, for the rest, are difficult to eliminate, such as dioxins.