Physisorption

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Physisorption^[1] or physical adsorption is a type of adsorption in which the adsorbate adheres to the surface only through Van der Waals force (weak intermolecular) interactions, the same that are responsible for the imperfection of real gases and the condensation of vapors. It is characterised by:^[2]

• Low temperature, always under the critical temperature of the adsorbate;
• Type of interaction: Intermolecular forces (van der Waals forces);
• Low enthalpy: ΔH < 20 KJ/mol;
• Adsorption takes place in multilayers;
• Low activation energy.
• The energy state of adsorbate is not altered.
• Reversible.

[edit] Examples

N₂ on iron at 80 K

[edit] See also

Adsorption

Chemisorption

[edit] Notes and References