
Activated Carbon Basics
If you are new to the industry, or just have questions about a specific area, you should find this primer helpful. For additional resources, follow the links in the right hand column.
What Is Adsorption?
Activated carbon removes impurities from fluids (liquid or gas) by a process called adsorption. Adsorption is a surface phenomenon that results in the accumulation of molecules on the surface of the internal pores of an activated carbon. This occurs in pores slightly larger than the molecules that are being adsorbed, which is why it is very important to match the pore size of the activated carbon with the molecules you are trying to adsorb. |
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The impurity molecules are held within the carbon's internal pore structure by electrostatic attraction or chemical bonding and accumulate on the solid surface of the carbon pore walls.
Carbon Type
|
Total Pore Volume mL/g |
Mean Pore Radius in Angstroms |
Surface Area m2/g
|
Gas Phase |
|
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|
Coconut Shell |
0.5 – 0.6 |
10 – 11 |
1000 – 1100 |
Peat |
0.6 – 0.7 |
11 – 12 |
1000 – 1275 |
Bituminous Coal |
0.6 – 0.7 |
12 – 14 |
1000 – 1150 |
Liquid Phase |
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|
Bituminous Coal |
0.7 – 0.8 |
14 – 16 |
900 – 1050 |
Lignite Coal |
0.9 – 1.0 |
29 – 32 |
600 – 675 |
Peat |
1.1 – 1.2 |
23 – 26 |
900 – 1050 |
Wood
(Chemically activated) |
1.4 – 1.8 |
22 – 26 |
1200 – 1600 |
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