Activated Carbon for Water Filtration: How does it work?

Activated carbon has been in the market for quite a long time. But, you must have been wondering why the very same ingredient is being used for a range of applications. Activated carbon can be used for aspects such as water filtration, teeth whitening, medical applications, and even as a critical element for life support in the outer space.

Activated carbon today has become a critical component for applications in a range of sectors, which include cosmetic, medical, as well as agriculture. The most popular is the use of activated carbon for water. This versatile product is crucial for the filtration of water in the best possible way.

So, what makes this ingredient so immensely effective?

In this blog, we will talk about the unique features of using activated carbon & why it is an optimum choice for filtration of water.

Activated Carbon: What is it?

Also popular by the name, “Activated Charcoal,” this ingredient is a variant of carbon that undergoes processing to possess a massive surface area. The tiny & low-volume carbon pores present within the surface allows for proper absorption & several variants of chemical reactions.

A gram of the activated carbon houses more than 32,000 ft2 surface area. This means one teaspoon of activated carbon will comprise roughly one large football field area. This area coverage makes this compound extremely useful in a range of day-to-day applications. However, you can initiate more chemical treatment for the activated carbon in order to increase the absorbing properties.

The activated carbon particles are usually derived from any carbonaceous source available. Common examples of such sources include bamboo, wood, willow peat, sawdust, peach pits, coconut shell, petroleum pitch, coir, and so on. However, one needs to keep in mind that the activated carbon for water filtration isn’t the same as the activated carbon.

Activated carbon is created by two different methods which include:

  • 1- Thermal Activation
    In the thermal activation method, the prime material used is converted by the help of hot gases. Once the material is exposed to enough heat, it is introduced to steam in order to help enlarge the pores.
  • 2- Chemical Activation:
    In the chemical activation process, certain chemicals are introduced to your source material right before carbonization starts. Generally, the chemical which is used for this process is either a strong acid, base, or even salt. After this, the material can be exposed to high heat & hence the activation process becomes quicker.

How does the filter with Activated Carbon work?

The effectiveness of activated carbon for water filtration is mostly due to its large surface area. Physical absorption serves as the prime method for filtering out any constituent from a given substance with the use of activated carbon.

Apart from physical adsorption, activated carbon can also be used for the facilitation of chemical reactions. The most common example of the same involves the use of chlorine molecules. As the chlorine gets close to activated carbon, the molecules in both react to create chloride ions. This helps with the effective removal of chlorine from the water.

The overall amount of contaminants that can be removed by activated carbon for water or air completely depends on various factors. This includes the amount and type of pollutant, water/air temperature, acidity, and the time for which air/water is exposed to activated carbon.

The specific variant of the activated carbon used for the process can also determine the amount of filtration you will experience. Carbon molecules that come with massive holes can trap in the big & heavy molecules in the pollutant like the ones found within organic chemicals. On the other hand, fine and small pores help pick up the lighter and smaller contaminants. Manufacturers for activated carbon for water filtration tend to label all their products as per their overall absorption potential.

Activated Carbon Filter: Types

As of now, there are two variants of activated carbon that can be used for the purpose of water filtration. These two variants include the PAC (Powdered Activated Carbon) and the GAC (Granular Activated Carbon). In general, the PACs have a smaller molecule size as compared to GAC. PACs are generally more efficient when it comes to removing a range of prominent impurities from water.

  • 1-GAC Filters:
    Also termed as the “Fixed-Bed Carbon Filters,” the GAC filters comprise of cylindrical containers consisting of GAC particles. In this filter, water is poured into the container & as water flows via the system, your activated carbon particles help filter out the impurities.
    However, channeling can be a common issue with the GAC filters. Now, as the water enters through the chamber, the path with the least resistance is followed. This leads to underutilization of the carbon particles which might reduce the overall filtering efficiency. So, if you are looking for large scale activated carbon for water filtration, you might not consider this option.
  • 2- Carbon Block Filters:
    These filters are comprised of densely packed GAC and PAC particle blocks that vary in size. Here, water passes through the carbon block pores & as they travel through a carbon filter, the tiny particles can help remove a range of contaminants.

    The main advantage of using the block filters as opposed to the GAC filters boils down to channeling elimination. In the block filters, particles tend to be stationary & each of the particles can be used to provide maximum effectiveness with activated carbon for water filtration.

What does your activated carbon filter help remove?

Activated carbon for water can help remove pollutants such as:

  • Pesticides
  • Organic contaminants
  • Herbicides
  • Chlorine
  • VOCs
  • Asbestos
  • Arsenic
  • Radon
  • Mercury


Filters with activated carbon are even used in industries that are in constant need of water. This extra amount of water comes from the recycling of the contaminated one. A properly devised activated carbon filtration system can target pollutants without actually stripping the beneficial compounds present in water. This can help make your water healthy and safe for drinking or other day-to-day activity.

Looking for a reliable team for advanced solutions for your water filtration needs? Keiken Engineering is the best team to help you with high-tech management solutions for all kinds of industrial projects. To know more about our services, give us a quick call at +34910577254. You can also write to us at