Differences Between Granular Activated Carbon (GAC) and Powdered Activated Carbon (PAC)

The most common question in activated carbon selection is when to use granular activated carbon (GAC) versus powdered activated carbon (PAC). Both can be made from the same raw material, but their particle sizes, adsorption kinetics and modes of use are fundamentally different.

Structural Difference: Particle Size

Granular activated carbon typically consists of 0.6–4 mm particles and is used in fixed-bed columns. Powdered activated carbon is usually milled below 200 mesh. This size difference lets PAC start adsorption much faster, while GAC offers stable, long-lasting performance in continuous-flow systems.

Application Areas

• GAC: drinking/waste water filtration, air-gas treatment, VOC removal — continuous-flow fixed beds.
• PAC: sugar/beverage color removal, instant dosing in chemical processes, sudden contamination peaks.

Cost and Performance

Although PAC looks cheaper per unit, it is single-use and cannot be recovered. GAC has a higher initial cost but, because it can be reused many times through thermal regeneration, its total cost of ownership is lower in most continuous applications. The most reliable way to decide is an application-specific sample test.