Difference between adsorption and absorption
adsorption and absorption:
The difference between the words adsorption and absorption can seem terribly hard to recognize even at a first glance because of the hardly apparent, subtle difference of the spellings of the two words. Yet, they are similar in definition too and yet, bear some differences as well. Therefore, this article plans on dealing with those subtle differences and bring them to light which will in turn help give a more clearer definition to the two words as well as defining their differences as well.
What is adsorption ?
The term adsorption refers to the process of transferring of a volume onto a surface. It is a process which refers to a scientific process where a gas or liquid solute accumulates on the surface of a solid or, more rarely, a liquid (adsorbent), forms a molecular or atomic film. This word is not seen as used in the ordinary language as it refers to a more scientific base. It can be used for purposes such as removing impurities from a solution by adsorbing them onto a finely divided solid such as extracting activated charcoal for decolorizing solutions, or for medicinal use, build up of static charge on a glass rod, adsorption of proteins onto bio materials, spilling water on a shirt where fibres will hold the water until heat takes it away, etc.
What is absorption?
The term absorption to a transfer of a volume into a volume which is a permeation or dissolution of a volume of energy or mass into another volume of energy or mass. It is the chemical integration of one chemical into another such as drinking a glass of water becoming a part of that person’s system. More often, a substance is diffused into a liquid or solid to form a “solution” or when atoms, molecules, or ions enter in to some bulk phase such as gas, liquid or solid material. Some examples can be pointed out as the merging of electromagnetic energy into an object, gold dissolving into mercury, chlorine gas dissolving into water, etc.
What is the difference between absorption and adsorption?
While the two words seem very similar at a first glance and the meanings too differ very slightly, they refer to completely different phenomenons in a scientific context. Whereas adsorption refers to the process of transferring of a volume onto a surface, absorption to a transfer of a volume into a volume which is a permeation or dissolution of a volume of energy or mass into another volume of energy or mass. Also, while adsorption refers to an accumulation or a holding up of something, absorption refers to the merging of two or more components.
While adsorption is a surface phenomenon, absorption is a bulk phenomenon which indicates that while adsorption occurs only at the surface of the adsorbent, absorption occurs throughout the body of the material. Also, in adsorption, the concentration on the surface of adsorbent is different from that in the bulk while in absorption, the concentration happens to be the same throughout the material.
Another trait that differentiates the two phenomena is that the absorption rate remains same throughout the process and yet, the adsorption rate is high in the beginning and then decreases till equilibrium is attained. Also, while absorption is a word that is often used in normal day to day context, the term adsorption tends to be more specific to scientific processes.