Do You Really Understand Activated Carbon?

Activated carbon, with its advantages of good adsorption performance, high strength, easy regeneration, and economic durability, is increasingly widely used in various industries, including drinking water, purified water, winemaking, beverages, and wastewater purification. It plays a particularly indispensable role in the water purification industry, especially in pure water machines and ultrapure water machines.

I. What is the adsorption principle of activated carbon?

Activated carbon is a black powder or granular amorphous carbon. Its main components are carbon, oxygen, and hydrogen. Activated carbon has abundant internal pores, low bulk density, and a large specific surface area due to deep activation, allowing it to fully contact gases (impurities) and exhibit good adsorption properties, thus purifying the air.

II. Physical properties of activated carbon

Activated carbon is a non-polar adsorbent. Besides carbon, its main components include small amounts of oxygen, hydrogen, sulfur, moisture, and ash. It possesses excellent adsorption performance and stable chemical properties, is resistant to strong acids and alkalis, and can withstand water immersion, high temperatures, and high pressures without being destroyed. Activated carbon possesses a large specific surface area and highly developed micropores. It primarily functions through physical adsorption, but due to the presence of surface oxides, it also undergoes some chemoselective adsorption.

III. Chemical Properties of Activated Carbon

All elemental carbon is composed of the element carbon and therefore exhibits the same chemical properties as carbon. It is very stable at room temperature, remaining unchanged even when exposed to sunlight or contact with moisture, and does not react with common chemical reagents. However, its chemical reactivity increases significantly at high temperatures, manifesting as its flammability and reducing properties.

Flammability: ① Complete combustion in oxygen or air: produces carbon dioxide and releases a large amount of heat. ② Insufficient air, incomplete combustion: produces carbon monoxide in addition to carbon dioxide, and releases heat.

Reducing Properties: ① When dry charcoal powder and copper oxide are uniformly mixed and heated vigorously. ② Incandescent carbon can reduce carbon dioxide to carbon monoxide. ③ Incandescent carbon can reduce water vapor.