Application of Adsorption Chemistry Notes

Applications of Adsorption :

→ Some important applications of adsorption are as follow:

In production of high vacuum : When activated charcoal is placed in a vessel then the remaining traces of air can be adsorbed by it. This results in creating very high vaccum. Although the vessel is already exhausted by a vaccum pump as far as possible.
In treatment of diseases : A number of drugs are used to kill germs by getting adsorbed on them and hence save us from dangerous diseases.
In chromatographic analysis : Chromatographic analysis is totally based on adsorption. This technique finds a number of applications is analytical as well as in industrial fields.
In gas masks : All the gas masks are important devices. They consist of suitable mixture of adaorbents and activated charcoal. Gas masks are used to adsorb poisonous gases and thus to purify the air for breathing. It is used for breathing in coal mines to adsorb poisonous gases like CO, CH₄ etc.
In Dyeing cloth : Alum is used as mordant for dyeing clothes. It adsorbs particles of dye on it. Otherwise the particles of dye do not stick on cloth.
In controlling humidity: Aluminium and silica gels are used as adsorbents for removing moisture. Thus they are used for controlling humidity.
In removal of colouring materials from solutions : Animal charcoal is used to adsorb coloured impurities from the solution to make solution clean and colourless.
In separation of inert gases : Different inert gases are adsorbed to different extent on coconut charcoal at different temperatures. Hence with the help of coconut charcoal, we can separate inert gases from their mixture.

→ In Froth floatation process : Froth Floatation process is used to concentrate a low grade sulphide ore. In this process, pine oil and frothing agent are used to separate earthy impurities and silica. In this process, particles are adsorbed on the froth, which floats over the surface of liquid, which can be collected in another tank time to time while impurities are setteled down.

→ In adsorption indicators : Surfaces of certain precipitates such as silver halides have the property of adsorbing some dyes like eosion, fluorescein etc. and hence they produce characteristic colours at the end point.

→ Heterogeneous catalysis : Various metals like Fe, Ni, Pt, Pd etc. are used as catalyst in various processes such as contact process, Haber process, hydrogenation of oil etc. In heterogeneous catalysis, the reacting gases are adsorbed on the surface of catalyst. Hence heterogeneous catalysis is totally based on adsorption.

→ As a dry lubricant : Graphite, tale etc. are used as dry lubricant. The lubricant works on the principle of adsorption

→ In qualitative analysis : In qualitative analysis of basic radicals, the principle of adsorption is used. Certain tests like lake test for the qualitative analysis of Al³⁺ ion is based on adsorption because Al(OH)₃ has the capacity to adsorb the colour of blue litmus from the solution.

→ In cleansing action : Soaps and detergents work on the principle of adsorption to clean dirt from the cloth.