Air purification from organic pollutants by activated carbons and there is situ photoregeneration

Extractor hoods represent one of the main technologies for purifying indoor air in in domestic environments, in research laboratories and in industrial processes. Suction hoods are divided into hoods that expel the air from work environments or hoods that recirculate the air after having filtered it for the removal of odorous and/or toxic substances. The filtration system of these hoods is based on the use of active carbons (AC) which, thanks to their large surface area, are able to stop the organic molecules by adsorption, allowing the air to pass through. This process is instantaneous and highly efficient. The main disadvantage is constituted by the exhaustion over time of the adsorbing capacities of the carbons, which reach total exhaustion within a few months. When the carbon filters exhaust their adsorbing capacity, it is necessary to replace them or regenerate them through heat treatments. These operations are not possible in situ and therefore the filters are generally replaced with new ones, by sending the exhausted ones to regeneration, with a significant economic and environmental cost.