Pelletized Activated Carbon (PAC) is a powerhouse in filtration and purification, offering a highly effective, easy-to-handle form of activated carbon. Produced by compressing milled carbon particles into uniformly sized cylindrical pellets, PAC combines high surface area with mechanical strength, low dust generation, and consistent flow properties.
PAC manufacturing begins with raw materials such as bituminous coal, coconut shells, or wood. These are carbonized and activated—often in high-temperature steam or CO₂ environments—to maximize porosity and surface area (500–2,000 m²/g). Milling and pellet pressing follow, creating dense, durable pellets typically between 2–5 mm in diameter. A final activation may burn off binders and refine pore structure.
This consistent pellet form brings practical advantages. Unlike powders which may cake, clog, or generate airborne dust, PAC flows easily, resists abrasion, and distributes uniformly in packed beds. It’s easier to store, transport, and dose—ideal for continuous systems like gas mask cartridges, industrial gas purification towers, or sewage treatment plants.
PAC excels at adsorbing organic compounds, chlorine, ozone, odor-causing gases, and volatile organic compounds (VOCs). In water treatment, it removes natural organic matter that can react with disinfectants to form harmful byproducts like trihalomethanes. In air treatment, it adsorbs industrial solvent vapors, paint booth emissions, and NO₂ or SO₂ exhaust.
Medical and respiratory applications also rely on PAC’s compact form. Gas mask filters with PAC layers protect users by physically trapping toxic gases. Air purification units use PAC cartridges to freshen indoor air in hospitals, laboratories, and biological safety cabinets. In food and beverage plants, PAC removes off-flavor compounds and chlorine—helping products retain quality and taste.
Performance is dictated by pore size distribution and surface chemistry. Larger macropores allow rapid flow and transit during adsorption, while micropores increase adsorption capacity. Pellet hardness is crucial for long-term use, dictating how often media must be replaced. For aqueous systems, PAC must withstand high flow rates; for air, resistance to humidity is key.
Sustainability is gaining focus. Coconut shell PAC, made from renewable biomass, sequesters carbon and is biodegradable at end-of-life. Regeneration systems—thermal or steam-based—allow spent PAC to be reused multiple times, reducing waste and costs. Emerging technologies include impregnated PACs (e.g. with potassium iodide) that enhance removal of specific pollutants like mercury or ammonia.
Selectivity is another frontier. Molecularly imprinted PAC has pore structures tailored to specific chemicals, offering precise removal in complex liquid mixtures. In gas separation, impregnated PAC can capture acid gases selectively in flue streams. Hybrid PAC-sorbent beds with zeolites or metal-organic frameworks blend high adsorption capacity with catalytic breakdown of VOCs.