Activated carbon is a black porous solid material composed of carbon, with small amounts of oxygen, hydrogen, sulfur, nitrogen, chlorine, and other elements. It is produced by crushing and shaping coal or by carbonizing and activating uniform coal particles. The specific surface area of regular activated carbon ranges from 500 to 1700 m²/g. It possesses strong adsorption capabilities and is widely used as an industrial adsorbent.
Classification based on materials:
1. Coal-based granular activated carbon: Made from high-quality bituminous coal through advanced refining processes, it appears as black irregular particles. It has developed pore structures, a large surface area, strong adsorption capacity, high mechanical strength, low bed resistance, good chemical stability, easy regeneration, and durability.
2. Coconut shell activated carbon: Produced by refining coconut shells, it appears as irregular particles. It has high mechanical strength, a developed pore structure, a large surface area, fast adsorption speed, high adsorption capacity, easy regeneration, and durability.
Activated carbon is mainly used for odor removal, heavy metal removal, dechlorination, and liquid decolorization in food, beverages, alcoholic drinks, air purification, and high-purity drinking water. It is also widely employed in solvent recovery and gas separation in the chemical industry.
For air purification, the pore diameter of activated carbon must be slightly larger than the diameter of toxic and harmful gas molecules to possess adsorption capabilities. The key factors affecting the lifespan of activated carbon used for air purification are the total amount of harmful substances in the environment and the frequency of desorption. Since the quantity of harmful gases in ordinary household air is much smaller than the amount of activated carbon used, the activated carbon can be used for a long time by regularly placing it under sunlight for disinfection.
