PHOTOCATALYSIS: HOW IT FIGHTS POLLUTION
Light and oxygen in the air, in contact with TiO2, trigger a photocatalytic reaction resulting in decomposition of organic and inorganic substances present in the atmosphere.
The principal substances responsible for pollution are nitrogen oxides (NOx), particulate matter (PM10) and VOCs (Volatile Organic Compounds).
Nitrogen oxides (NOx) are a random blend of nitrogen monoxide and nitrogen dioxide. Nitrogen dioxide is formed in the atmosphere out of the nitrogen monoxide produced primarily by burning fossil fuels, as for example in car engines.
The World Health Organisation says that nitrogen dioxide is very harmful for the health: long-term exposure can compromise the functioning of the lungs and increase the risk of respiratory pathologies. Nitrogen dioxide is in fact irritating to the mucous membranes, and can contribute to various alterations of lung functioning, chronic bronchitis, asthma and pulmonary emphysema. Long-term exposure even to low concentrations drastically decreases the lungs’ defences, increasing the risk of respiratory infections.
The effects of nitrogen dioxide appear hours after exposure, so that people do not normally realise that their problems are due to the polluting air they have been breathing.
The term "particulate matter" refers to all particulates suspended in the air with an aerodynamic diameter of less than 10 thousandths of a millimetre.
The principal sources of PM10 are in human activity: combustion processes (including those in internal combustion engines, heating systems, numerous industrial activities, incinerators and thermoelectric power plants), wear on tyres, brakes and asphalt. A large part of the PM10 in the atmosphere is the product of transformation of certain gases into liquid or solid particles (nitrogen and sulphur compounds) emitted by human activities.
Precisely because of their small size, these pollutants can penetrate the respiratory system beyond the larynx. Pathologies caused by pollution from particulates includeasthma, cardio-pulmonary infections and compromised lung functioning.
VOLATILE ORGANIC COMPOUNDS (VOCs)
The term Volatile Organic Compounds (VOCs) refers to a series of substances in liquid or vaporous form with a boiling point ranging between a minimum of 50-100°C and a maximum of 240-260°C. The term “volatile” indicates the capacity of these chemical substances to evaporate easily at ambient temperature. More than 300 compounds fall in this category.
Urban VOCs are produced almost exclusively by combustion in motor vehicles, coal-fired power plants, incineration and evaporation of solvents and fuels.
VOCs are also generated by use of cleaning products, paints, pesticides, glues and adhesives, printers and photocopiers, tobacco smoke, etc.
The photocatalysis process triggered by TiO2 in ACTIVE Clean Air & Antibacterial Ceramic™ tiles breaks down the pollutants and toxic substances listed above and transforms them into innocuous compounds such as nitrates, sulphates and carbonates.
The final result is a significant reduction in toxic pollutants (under standard ISO 22197-1) produced by automobiles, factories, home heating systems and other sources.
The result is an improvement in the environment and the quality of the air we breathe, offering clear benefits for human health.