Activated carbon, also called activated charcoal, is a form of carbon that has been treated to have small, low-volume pores that increase its surface area. This results in a material with a very large internal surface area available for adsorption or chemical reactions. The word “activated” in the name refers to the fact that activation is necessary to create these low-volume pores; without activation, the charcoal would be mostly useless.
The term “activated carbon” covers a wide variety of materials, each with their own specific properties and uses. The best type of activated carbon for any given application depends on factors such as the adsorbate (the substance being removed from the gas or liquid), the nature of the process stream (continuous or batch), and operating conditions such as temperature and pressure.
One common type of activated carbon is made from coconut shells. Coconut shell activated carbon has good physical strength, high abrasion resistance, and good chemical stability. It is commonly used in water treatment applications. Another common type is made from coal. Coal-based activated carbons have a lower cost than those made from other materials but they may not be as effective at adsorbing certain contaminants.
When choosing an activated carbon for your application, it is important to consult with an expert to determine which type will work best for you.