What is the difference between Absorption and adsorbtion

[bejoy]

Hi,

Friends,

I would like to know what is the difference between Absorption and adsorbtion need a clear definition and also with an example kindly help me

regards

[hassanmahmoodi]

Hi
Adsorption:
The phenomenon of attracting and retaining the molecules of a substance on the surface of a liquid or a solid resulting into a higher concentration of the molecules on the surface is called adsorption. The substance thus adsorbed on the surface is called the adsorbate and the substance on which it is absorbed is known as adsorbent. The reverse process i.e. removal of the adsorbed substance from the surface is called desorption. The adsorption of gases on the surface of metals is called occlusion.

Difference between Adsorption and Absorption:
ADSORPTION
1-It is surface phenomenon i.e. it occurs only at the surface of the adsorbent.
2-In this phenomenon, the concentration on the surface of adsorbent is different from that in the bulk.
3-Its rate is high in the beginning and then decreases till equilibrium is attained.
ABSORPTION
1-It is bulk phenomenon i.e. it occurs throughout the body of the material.
2-In this phenomenon, the concentration is same throughout the material.
3-Its rate remains same throughout the process.

[adrian423]

Quantachrome have a particle characterisation dictionary with this definition:

adsorption (noun) - the adhesion of atoms, gases, solutes or liquids (the adsorbate) to the surface of a solid or liquid (the adsorbent). Note the difference with absorption where one fluid permeates into the other material.

From http://www.quantachrome.co.uk/en/dictio ... rption.asp

hope that helps