Activated Carbon Air Filter‌

An activated carbon air filter is a filtration device that utilizes the adsorption properties of activated carbon to remove odors and harmful gases from the air. Its core function is based on the porous structure of activated carbon, which provides a vast surface area for effective adsorption of airborne contaminants.

‌Working Principle‌

Activated carbon filters primarily operate through ‌physical adsorption‌ and ‌chemical adsorption‌. Physical adsorption relies on intermolecular forces, while chemical adsorption occurs when activated carbon is impregnated with specific chemicals, enabling selective adsorption of targeted harmful gases. The micropores in activated carbon typically range from 2 to 50 nm in diameter, offering a surface area of 500–1500 m² per gram, ensuring strong adsorption capacity.

‌Key Applications‌

Activated carbon filters are widely used in:

• ‌Industrial settings‌: For exhaust gas treatment, removing odors and harmful gases like SO₂, NH₃, etc.
• ‌Precision equipment‌: As a final protective layer to ensure clean operating environments.
• ‌Buildings & public facilities‌: In pharmaceuticals, food processing, electronics, and nuclear industries for air purification.

‌Types & Structures‌

Activated carbon filters are available in ‌granular‌ (e.g., wood, coconut shell) and ‌fiber-based‌ forms, with the latter offering faster adsorption. Common designs include panel, multi-cylinder, and pleated filters, some of which integrate pre-filters or HEPA layers to save space.

‌Selection & Maintenance‌

When choosing a filter, consider pollutant type, concentration, airflow, and space constraints. Maintenance involves monitoring weight gain (indicating saturation) and replacing the filter when downstream gas concentrations exceed limits. Upstream and downstream installation of HEPA filters is recommended to prevent clogging.

‌Comparison with Other Technologies‌

Unlike HEPA filters (which excel at capturing particles like PM2.5), activated carbon filters specialize in adsorbing gaseous pollutants (e.g., formaldehyde, VOCs). Electrostatic precipitators may generate ozone and are less effective against gases.