Awareness of the importance of air quality for Human health and well-being has increased significantly over the past 15 years, leading to stricter performance requirements for air filtration systems. However, air quality challenges extend far beyond particulate removal: harmful gaseous pollutants such as VOCs, NOx, and SO₂ can easily pass through conventional filter media, impacting health, comfort, and overall performance.

At the same time, the emergence of new vehicle technologies replacing traditional combustion engines has created the need for advanced filtration solutions to protect sensitive and costly components—such as catalysts used in fuel cell vehicles—from gaseous contaminants.

To meet these growing needs, Ahlstrom, a global leader in sustainable and innovative fiber-based materials, has developed a new production platform for molecular filtration media designed to efficiently remove particles, fine particles, and harmful gases simultaneously pollutants. More specifically, target markets include cabin air, HVAC systems, and fuel cell air intake filtration supporting the shift toward Non-Combustion Engine vehicles.

From a technological perspective, gaseous pollutant removal relies on mechanisms fundamentally different from those used for particulate filtration, and most applications require the use of solid adsorbents. These adsorbents range from granular activated carbon to more advanced materials such as impregnated activated carbons or ion exchange resins, depending on the target contaminants, application environment, and specific requirements. In this context, the new Ahlstrom platform—PurXcel™—was designed to provide high versatility and flexibility, both in the choice and combination of solid adsorbents, and in the configuration of the particle filtration layer, which can range from standard electrostatically charged materials to multilayer solutions combining charged media with advanced electrospun nanofibers.

This article and presentation will detail two concrete examples demonstrating how this platform enables innovative solutions in premium cabin air filtration and fuel cell air intake applications. The first example highlights the benefits of electrospun nanofibers compared to conventional charged media, while the second showcases the potential of ion exchange resins for removing basic gas contaminants such as NH₃.