What is the Difference between Adsorption and Absorption?

They sound very similar don’t they? In fact, I wouldn’t blame you for not even noticing that there was a difference! But, these two words are very different and “adsorption” is the principle that charcoal uses. In this article, we will discuss the differences between these two words.

I like this definition I found:

1. Absorption happens when atoms pass through or enter a bulky material like sponges.
2. Adsorption happens when the atoms settle or accumulate on the surface of a material rather than literally entering or diffusing into that same material. 1

In other words, absorption is what happens when you place a dry sponge in water. The water enters the fibers of the sponge.
Adsorption on the other hand is what happens when you place your hand in the water and take it back out, to discover that your hand is wet. The water sticks to the outside of your hand.

Each tiny particle of charcoal has millions of microscopic spaces that give it a massive surface area. One gram of activated charcoal can have a surface area in excess of 3,000 square metres! That’s about half a standard house block! With that large amount of surface area, you can see why charcoal is such a good adsorber.

Joel Ridgeway

References

1 DifferenceBetween.net, Difference Between Adsorption and Absorption, Copyright © 2011 - http://www.differencebetween.net/science/difference-between-adsorption-and-absorption/#ixzz1GGWfXCNa