Granulated Activated Carbon for Superior Filtration

High-Performance Coconut-Shell GAC for Water, Air & Gas Purification

Activated Carbon Products

What Is Granulated Activated Carbon?

Granulated Activated Carbon (GAC) is a porous, adsorbent material produced by activating carbon-rich feedstocks—most commonly coconut shells—to develop a high internal surface area. The “granulated” format refers to particles sized roughly 0.2 to 5 mm, providing an optimal balance between surface area and flow characteristics for fluid-phase applications.

How GAC Is Made

Selection of Feedstock:
- Coconut shells (preferred for hardness and pore development)
- Wood, coal or peat (alternative feedstocks)
Carbonization:
- Pyrolysis at 400–700 °C in an oxygen-limited environment to remove volatiles.
Activation:
- Steam or chemical activation (e.g., phosphoric acid) at 800–1,000 °C to enlarge internal pores.
Sizing & Washing:
- Milling to granule range (0.2–5 mm)
- Acid/base washing to remove residual activation agents and ash.

Key Physical & Chemical Properties

Property	Typical Range
Surface Area	800–1,200 m²/g
Pore Volume	0.5–0.8 cm³/g
Bulk Density	0.45–0.55 g/mL
Hardness (Abrasion #)	≥ 95% retention after mechanical stress
pH (10% slurry)	6.5–8.5
Moisture Content	≤ 5%

Applications of GAC

1. Water Treatment

Drinking Water Filtration: Removes chlorine, organics, taste & odor compounds.
Wastewater Polishing: Adsorbs pharmaceutical residues, dyes, and micropollutants.
Point-of-Use (POU) Cartridges: Common in under-sink and countertop filters.

2. Air Purification

Activated Carbon Air Filters: Remove volatile organic compounds (VOCs), odors, and airborne chemicals.
Indoor Air Quality Systems: Often integrated into HVAC for mold, smoke, and VOC control.

3. Gas-Phase Adsorption

Industrial Gas Treatment: Captures sulfides, ammonia, and VOCs from process streams.
Personal Protective Equipment: Carbon beds in respirators and gas masks.

4. Industrial & Specialty Uses

Food & Beverage: Decolorization of syrups, sugar refining, and deodorizing edible oils.
Gold Recovery: Adsorption of gold cyanide complexes in mining operations.
Pharmaceuticals: Purifying reaction intermediates and solvents.

Benefits of Coconut-Shell GAC

Superior Hardness: Low dust generation, long bed life in fixed-bed systems.
High Microporosity: Exceptional removal of small molecules (e.g., benzene).*
Renewable Feedstock: Coconut shells are an agricultural byproduct.
Eco-Friendly Production: Lower greenhouse gas footprint vs. coal-based GAC.

Choosing the Right GAC

Particle Size Distribution:
- Smaller granules → higher surface area, lower flow → POU filters.
- Larger granules → lower pressure drop, higher flow → bulk water treatment.
Iodine Number:
- Indicator of micropore content; choose higher iodine numbers (≥ 1,000 mg/g) for organic removal.
Hardness & Abrasion Resistance:
- Critical for systems with backwashing or mechanical agitation.
Regeneration Capability:
- Thermal vs. chemical; check thermal stability (≥ 900 °C) for multiple cycles.

Regeneration & Disposal

Thermal Regeneration:
- On-site retorting to desorb contaminants at 800–900 °C.
- Restores ≥ 90% of original capacity over multiple cycles.
Chemical Regeneration:
- Acid/base washes; suitable for specific contaminant classes.
Safe Disposal:
- Spent GAC classified based on adsorbed contaminants—hazardous vs. non-hazardous.
- Landfill or incineration per local environmental regulations.

GAC vs. Other Activated Carbon Forms

Feature	GAC (Granular)	Powdered AC (PAC)	Extruded AC (EAC)
Particle Size	0.2–5 mm	< 0.18 mm	1–3 mm cylindrical
Surface Area	800–1,200 m²/g	600–800 m²/g	700–1,000 m²/g
Pressure Drop	Moderate	High (packed beds)	Low
Applications	Fluid treatment	Batch dosing in water	Gas-phase adsorption