According to IUPAC (International Union of Pure and Applied Chemistry Nomenclature), the classification is as follows:
| Micropores | Micropores with sizes less than 2nm
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| Mesopores | Pore size ranging between 2 and 50nm |
| Macropores | Pore size equal to 50nm or more |
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| Pore structure model of activated carbon | Adsorption process model of activated carbon |
ADSORPTION PROCESS OF ACTIVATED CARBON
Step 1 Molecules of adsorbed media are moved to the surface of adsorbing media (activated carbon)
Step 2 Molecules of adsorbed are dispersed through macropores and mesopores of activated carbon
Step 3 Molecules of adsorbed fill micropores or combine with inner surfaces of micropores
Note:
Adsorption is accumulation (combination) of molecules of adsorbed media on adsorbing surfaces and adsorption volume depends on specific surface area (pore volume) adsorbing media.
Adsorption takes place mostly in microspores and several mesopores
