I'm confused about the difference between carbon and charcoal filters. Ultimately, charcoal contains carbon but I have come across an exam question that asks for their individual roles in a water filter.

I have done some research and found this page that states that 'activated carbon' and 'activated charcoal' can be used interchangeably.

Would any of you be so kind as to help me decipher the individual role of carbon filter and a charcoal filter in an ideal water filter?

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    $\begingroup$ Activated carbon is usually of higher quality than activated charcoal, but the words are often used interchangably. $\endgroup$ Commented Aug 1, 2016 at 9:37

2 Answers 2


First of all and I want to clarify something that it often misunderstood, which is that charcoal has carbon but it is NOT carbon. Charcoal actually have a bit of residual Hydrogen and oxygen in it and is again NOT carbon.

Carbon is a pure element that occurs naturally in a variety of allotropes. Charcoal is the charred product from pyrolyzing wood. Carbon is found as graphite and diamond and has no intrinsic filtering properties. Charcoal is a porous material that can burn or adsorb pollutants. Activated charcoal is charcoal which has been specially processed to have a very high surface area. This surface is what pollutants adsorb (not a(b)sorb) to to be remove from air and water. If you said activated charcoal or activated carbon anyone would know what you were talking about, but activated charcoal is more proper as the material is in fact charcoal, NOT carbon.


Carbon filters use activated carbon, which is a highly porous material with a large surface area. This makes it very effective at adsorbing impurities, such as chlorine, volatile organic compounds (VOCs), and heavy metals.

Charcoal filters use charcoal, which is a type of carbon that has been burned in the absence of oxygen. Charcoal is also porous, but it has a smaller surface area than activated carbon. This makes it less effective at adsorbing impurities.

Another difference between carbon and charcoal filters is that carbon filters are typically more expensive than charcoal filters. However, carbon filters are also more effective at removing impurities.

Property Carbon filter Charcoal filter
Material Activated carbon Charcoal
Surface area High Low
Effectiveness More effective Less effective
Cost More expensive Less expensive

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