SYSTEM FOR ABATING THE MAGNETO-PHOTOCATALYTIC ATMOSPHERIC POLLUTION The present invention refers to an atmospheric pollution abatement system. The air we breathe can be contaminated with pollutants such as nitrogen oxides (NO _x ), sulfur dioxide (SO ₂ ), ozone (O ₃ ), carbon monoxide (CO), hydrocarbons (HC) and particulate matter (PM), with particles of different sizes. In urban areas, these pollutants are emitted mainly by on-road and off- road vehicles, but there are also contributions from power plants, industrial boilers, incinerators, petrochemical plants, airplanes, ships and so on, depending on the locality and prevailing winds. Fine particles represent the atmospheric pollutants with the main impact on the health of the population. Emissions of anthropogenic origin, in fact, have for a long time reached concentration levels considerably higher than the absorption capacity of the planet Earth and represent the main cause of alterations in air quality, numerous diseases and multiple factors of incidence. on health and in the environment in which we live. The high concentration of fine particles in urban areas mainly derives from the consumption and lifestyle of individuals, mainly due to:

- emissions from domestic heating (in particular diesel, coal and wood) and household appliances;

- residues from the wear of the road surface, brakes and tires of the cars;

- emissions deriving from the operation of internal combustion engines (trucks, cars, airplanes).

Their impact on human health depends on various factors, such as the amount of air pollutant to which one is exposed, the duration of exposure and the danger of the pollutant itself; the health effects can be small and reversible, such as eye irritation, or debilitating, such as an aggravation of asthma, or even fatal, such as cancer.

Globally, cities are responsible for over 40% of overall greenhouse gas emissions and are the areas most vulnerable to the effects of climate change; in particular, the concentration levels of particulate matter in urban areas remain at extremely dangerous values for health, especially of PM 10, PM 1 and PM 2.5.

The need to limit the presence of pollutants in the air often involves the use of various abatement systems now indispensable in industrial activities, responsible for the production of airborne pollutants in large quantities. Over the last few years, many fixed or portable devices have been created in order to purify the air in confined working or small living spaces. Various strategies have been advanced by the scientific community in order to find solutions to the problem of air contamination, however most have been substantially aimed at reducing pollution by acting on the emission sources of pollutants while none, concrete, has been applied in the urban contexts where people live and work.

According to the state of the art, one of the most promising innovations in the civil field for the abatement of pollutants is represented by the introduction of photo-catalyst materials (such as titanium dioxide TiO2) in construction and finishing materials. Furthermore, the ability of plants and trees to capture air pollutants is also being studied: they break down the particulate matter suspended in the atmosphere by modifying the air flows, increasing turbulence but also knocking it down directly on their surfaces, in particular on the leaves. This occurs depending on the climatic and environmental characteristics and those of the vegetation present (height and diameter of the foliage), including roofs and green walls. The filtering capacity of the vegetation increases with the increase in coverage of the foliage per unit of surface and the large trees with developed foliage intercept a greater volume of air, causing the dust and particulate matter to fall to the ground. Green belts can therefore be effective in reducing dust and particles generated by motor vehicles on the roads, in particular if they are located near the sources of pollution and are composed of low and dense vegetation, so as to offer a large deposition surface for particulate matter. The state of the art also includes magnetic air filtration based on the principle of electrostatic precipitation: these filters purify the air with high efficiency (up to 99.9%) both in terms of purification and energy, and have the natural advantage of allowing the washing of the cells, which always allows a constant operation and maximum effectiveness.

In the art, many systems for reducing atmospheric pollution are known, such as for example the document CN110787784 which describes a device and a method for the photocatalytic degradation of VOCs (Volatile Organic Compounds) using a matrix of TiO2 nanotubes of the metal mesh type which can be used as a catalytic material of an air purification agent, and finds its application to effectively solve the damages of the internal formaldehyde to a human body, or the document W02020/025747 which describes an air purification device comprising a filtration system using a photocatalytic process with a catalyst such as TiO2 and an ultraviolet source.

The main disadvantage of the existing approaches is the limit to the use of the magnetic filtration process as well as an air quality monitoring system such as the one described in the applicant's W02018/225030 document; moreover, the known technique is focused on magnetic filtration techniques based on the use of solvents to dilute the polluting particles contained within. Object of the present invention is solving the aforementioned prior art problems by means of an atmospheric pollution abatement system (100), with low maintenance and contained volumes capable of operating also within the urban fabric, which combines different chemical-physical principles to minimize the energy costs of the abatement of different pollutants from the atmosphere and which uses both a magnetic system and a photocatalytic system, both able to remove polluting dust through a specially implemented mechanism.

Another object of the present invention is the possibility of providing monitoring of the level of pollutants present in the air by means of an innovative system, of compact size and with extremely low energy consumption.

The aforesaid and other objects and advantages of the invention, as will emerge from the following description, are achieved with an atmospheric pollution abatement system such as that described in claim 1. Preferred embodiments and non-trivial variants of the present invention form the subject of dependent claims.

It is understood that all the attached claims form an integral part of the present description. It will be immediately obvious that innumerable variations and modifications (for example relating to shape, dimensions, arrangements and parts with equivalent functionality) can be made to what is described without departing from the scope of the invention as appears from the attached claims.

The present invention will be better described by some preferred embodiments, provided by way of non-limiting example, with reference to the attached drawings, in which:

- FIG. 1 shows the functional diagram of an atmospheric pollution abatement system (100), according to the present invention;

- Fig. 2 shows the magnetic filtration system (2) with permanent magnets (8);

- Fig. 3 shows the magnetic filtration system (2) with the permanent magnets (9) detached and the corresponding mechanism (13)

- Fig. 4 shows the photo-catalysis system with the light source (10) and the catalyst (11);

- Fig. 5 shows the air suction system (1) with suction fan (12); and

- Figures 6 to 9 show detailed and constructive embodiments of the components in Fig. 1.

The atmospheric pollution abatement system (100) is based on an air suction system (1) designed to suck air from the external environment, a magnetic filtration system (2) designed for the purification of air from contaminants in urban and extra-urban environments, a photo-catalytic system (3) designed for the decomposition of gaseous pollutant molecules, a photovoltaic power source (7) designed to supply the atmospheric pollution abatement system (100) with sufficient energy for its operation, and a control block (5) designed to ensure the operation of the magnetic filtration system (2), the photocatalytic system (3) and the air quality monitoring system.

Advantageously, the magnetic filtration system (2) consisting of a metal cylinder, connected at the inlet to the air suction system (1), is composed of a structure designed to purify the air from all metal particles (PM10) which constitute the air-dispersed particulate in urban and extra-urban environments, which binds the dust to the permanent magnets (8) adhered to the walls of the cylindrical structure during the capture phase, and by an apparatus designed to allow the dust to fall into the base of the arrangement by detaching the permanent magnets (9) activated by a suitable movement mechanism (13); at the next purification cycle, the permanent magnets are again placed in contact with the metal cylinder.

Air then passes through the photocatalytic system (3) in which a light source (10) connected to it emits electromagnetic radiation in the ultraviolet spectrum and activates the catalyst (11) based on titanium oxide in anatase crystalline form (TiO2) connected therein, capable of decomposing the gaseous molecules of pollutants such as nitrogen oxides (NOX), sulfur oxides (SOX) and ozone (O3), and which at the end of the cycle releases the purified air into the external environment (4).

In particular, titanium dioxide (TiO2) in a crystalline form absorbs the photons with energy corresponding to the energetic "jump" in the relative excited state, and activates the relaxation mechanisms that notoriously lead to chemical reactions. Three different relaxation mechanisms have been identified:

- charge transfer: it is an electronic mono- reaction in which an electron passes from a high energy orbital of a donor species to a lower energy orbital of the acceptor species. The final products will be an ion pair formed by a donor cation and an acceptor anion.

- Electronic exchange: consists of two independent electronic transfers in the adsorbateadsorbent and adsorbent-adsorbate directions, and the final result is an energy transfer.

- The dipole-dipole coupling: it occurs through Coulomb interactions between the dipole of the photo-excited species and the induced dipole of the quencher.

Subsequently, after the adsorbed species has been excited through one of the mechanisms described above, it is in a state in which its reactivity is stimulated and can give rise to chemical reactions with molecules present in its surroundings. To improve the effectiveness of the photocatalytic action, various catalysts have been prepared with increasing TiO2 concentrations (5, 10, 15%), with intermediate electronic conductivity between that of a conductor and that of an insulator. From the experimental evidence the isolated N atoms, characterized by occupied and empty atomic orbitals, were assembled together in a compact crystal lattice.

The atmospheric pollution abatement system (100) is advantageously provided with a photovoltaic power source (7), or alternatively with a battery, connected to the magnetic filtration system (2) and to the air quality monitoring system (6), which consists of a set of panels sized to supply energy to the suction fan (12) in the suction block (1), to the light source (10) in the photocatalytic system (3), to the movement mechanism of the permanent magnets (13) and the air quality monitoring system (6).

Furthermore, the air quality monitoring system (6) provides information and statistics on the concentrations of airborne pollutants, in particular the measured quantities are represented by fine particles PM10, PM2.5 and PM1, nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), carbon monoxide (CO), hydrogen sulphide (H2S) and volatile organic compounds (VOCs), as well as temperature, pressure, relative humidity, wind direction and intensity, and sends to the control block (5) which manages the information on the concentrations of airborne pollutants also acquired by the photocatalytic system (3) and by the magnetic filtration system (2).

The proposed air pollution abatement system (100) includes several streams that can be classified as mass, information and energy flows: the mass flows (indicated with a solid black line in Figure 1 are those that characterize the passage of air through the part of suction (1), filtration (2), photo-catalysis (3) and output (4); the information flows, indicated with a black dotted line in figure 1, are represented by the data measured by the monitoring unit (6) and by the information exchanged between the control block (5) and the magnetic filtration and photo-catalysis parts (2,3); the energy flows, indicated with dashed line and black dot in figure 1, represent the connection between the photovoltaic system (7) and the monitoring unit (6) and the photo-catalysis system (3).

The atmospheric pollution abatement system (100) proposed by the applicant is equipped with a magnetic filtration system capable of removing the metal particles constituting the atmospheric particulate matter (PM10) with high efficiency (about 99%); combined with the photocatalytic system it also allows the removal of airborne polluting gases. Furthermore, the air pollution abatement system (100) requires a very low energy requirement and this makes it easy to install in many points within both an urban and extra-urban context, also considering its small size and low maintenance, with frequency annual, which it needs.