

Moreover, advancements in technology have led to the development of more sophisticated air purification systems, such as those that utilize photocatalytic oxidation. This method employs UV light to activate a catalyst, which in turn breaks down organic pollutants into harmless substances. This technique not only targets VOCs but also eliminates bacteria and viruses, making it an excellent choice for hospitals and other places where hygiene is paramount.
Another important category is the gas-phase filter, which targets gaseous pollutants such as volatile organic compounds (VOCs), sulfur dioxide (SO₂), and nitrogen oxides (NOₓ). These substances pose significant health risks and contribute to the phenomena of smog and acid rain. Chemical sorbents, such as activated carbon, zeolites, and silica gels, are commonly used in gas-phase filters to adsorb or react with these harmful gases, thus preventing them from entering the atmosphere.