Activated Carbon for Water Purification: Understanding the Types

In our journey to learn more about activated carbon for water purification, today we are going to discuss its different types used for industrial applications. Activated carbon is a popular option that is perfect for thorough water purification for both residential as well as commercial usage.

Before we go ahead and decode the types of activated carbon for water purification, let us understand what exactly activated carbon is.

What is Activated Carbon?

Also known by the name activated charcoal, this crude variant of graphite is actually different from the type of graphite that is used for creating pencil leads. Activated carbon is different from any other given the fact that it has an imperfect structure that is heavily porous with a large pore size & visible crevices and cracks that are present in its molecular dimension.

This particular graphite structure allows the carbon to possess a particularly massive surface area that allows it to absorb a broad range of chemical or organic compounds. Activated charcoal packs in the strongest possible forces for physical adsorption with the highest porosity and adsorbing volume.

Activated charcoal possesses a surface area that is higher than 1000m2/g. To sum it up, about 3 grams of activated carbon carries a surface area that is equal to that of a massive football field.

Now, you might ask what exactly adsorption is. So, here you go!

Adsorption is actually a process via which gaseous or liquid molecules are added to a solidified surface. This particular thing is different from that of absorption, where the molecules are actually absorbed by the gas or liquid item.

Activated Carbon: What are the types?

Activated carbon can be created from different types of substances that contain a very high concentration of carbon, like coconut shells, coal, as well as wood. These raw materials surely have a major influence on the performance and characteristics of this activated charcoal.

There are 100+ variants of activated charcoal for different types of purification applications, which include:

  • EAC or Extruded/Pelletised Activated Carbon
  • GAC or Granular Activated Carbon
  • Acid-Washed & High-Purity Activated Carbon
  • PAC or Powdered Activated Carbon
  • Specialist Impregnated Carbon

Let us take a look at some of the popular variants of activated carbon:

1. GAC or Granular Activated Carbon:

The GACs are irregular-shaped particulates that are sized within the range of 0.2 to 5mm. This particular activated carbon variant is used for both gases as well as liquid phase applications.

2. PAC or Powder Activated Carbon:

It is a pulverized carbon variant that has a size that is predominantly shorter than 0.18mm. Th4ese are primarily used for the liquid phase application & also for the treatment of flue gas.

3. EAC or Extruded Activated Carbon:

The EACs are cylindrical or extruded shaped carbon with diameters that range between 0.8-5mm. It is used primarily for gaseous phase applications given the fact that they have features such as high mechanical vigor, lower pressure descends, as well as low dust density.

Also, activated charcoal is available in different forms like fibers and cloth.

What causes molecules with activated carbon adsorb?

The process of adsorption occurs due to a variant of the Van der Waals Force, known as London Dispersion Forces, that exists between the molecules. This particular force serves in a manner that is similar to the planetary gravitational forces.

These forces are massively short-ranged & therefore particularly responsive to the overall distance between activated carbon’s adsorbate molecule & carbon surface. Not just that, the molecules are also a particular additive in nature, which means that this force is a sum of complete interaction between different atoms.

There are two types of adsorption:

  • Liquid-Phase Adsorption:

In this case, the molecules start going from the bulk category to the adsorption category while the pores are present in their semi-liquid state. Now, the adsorption driving force helps sum up the concentration ratio of compound solubility.

  • Gaseous-Phase Adsorption:

It is a condensation process in which the carbon’s adsorbing forces help condense all the molecules present in a bulk stage within the activated carbon pores. In short, the driving strength for adsorption serves as the ratio between vapor pressure and partial pressure of the carbon compound.

What are the compounds that can be adsorbed?

In general, almost every compound can be adsorbed to a certain extent. However, in practice, activated charcoal is used to adsorb the organic compounds with a larger inorganic molecular weight, such as mercury and iodine. So, the compound’s adsorbability increases with:

  • Increasing molecule polarizability, which is in relation with the molecule’s electron clouds
  • Increasing weight of the molecule
  • A towering number of the functional groups like halogen compounds or double bonds


With activated carbon, you can keep water in its cleanest and purest form to be used for commercial or residential applications. In order to save up on energy bills, you can make use of the activated carbon and achieve faster results with high-efficiency.

Are you looking forward to an energy-efficient procedure being implemented for your water filtration process? If so, Keiken Engineering is here to help you out! Our team of experienced professionals can help you achieve perfection in your filtration process with minimal glitches. To get in touch with us right away, give us a quick call at +34-91-057-7254 or write to us at