• Written By Pavithra VG
  • Last Modified 25-01-2023

Application of Adsorption: Definition and Examples

img-icon

Application of adsorption: Adsorption application is defined as the property of virtue by which solid substances are able to attract the surface molecules of certain solutions or gases. Adsorption is an external process and it is also stated to be a surface phenomenon which is having wide applications in the everyday life of humans.

Furthermore, adsorption and partition chromatography along with some of the other applications of adsorption chromatography will be discussed throughout this article. It will help the students to find out what are the exact ways by which adsorption is having its usage in the practical application process. So, without wasting any more time, let us get into the everyday application of the adsorption phenomenon which is going to provide lots of useful information to all the students.

Adsorption Definition: Overview

The process in which molecular, atomic, or ionic species of one substance accumulate at the surface of another is called Adsorption. Adsorption is defined as the phenomenon of attracting and retaining the molecules of a substance on the surface of a liquid or a solid, resulting in a higher concentration of the molecules on the surface. Adsorption is an exothermic process.

Components Required For Adsorption

Adsorbate: The substance which gets adsorbed on any surface is called adsorbate. For example, if gas gets adsorbed on a solid surface, then the gas is termed as the adsorbate.
Adsorbent: The substance on the surface of Adsorption that takes place is called adsorbent. Adsorbents may be a solid or a liquid. Metal powders, powdered charcoal, silica powder, etc., are the commonly used adsorbents. Activated charcoal, silica, alumina, etc., are very effective adsorbents due to their large surface area.

Application of Adsorption

The list of applications of Adsorption are discussed below:

1. Application of Adsorption In Gas Masks

The gas masks used as protective devices against poisonous gases such as methane \(\left( {{\rm{C}}{{\rm{H}}_4}} \right),\) chlorine \(\left( {{\rm{C}}{{\rm{l}}_2}} \right),\) sulfur dioxide \(\left( {{\rm{S}}{{\rm{O}}_2}} \right),\) etc., contain suitable adsorbents. The adsorbents preferentially adsorb poisonous gases and thus purify the air used for breathing. The common form of gas mask contains a layer of activated charcoal that adsorbs poisonous gases.

Adsorption Application In Gas Masks

2. Application of Adsorption In the Removal of Colouring Matter

The phenomenon of Adsorption is largely used for the removal of undesirable colouring matter from raw sugar solution, juices, vegetable oils, petroleum, etc. The adsorbent such as animal charcoal, activated charcoal, Fuller’s earth, etc., are used for this purpose.

3. Application of Adsorption In Dyeing

In dyeing, clothes are first kept dipped in a mordant (generally alum) and then in the solution of the dye. The mordant is first adsorbed on the clothes, and then the dye is adsorbed on the mordant. The mordant adheres well both to the fibre and the dye.

4. Adsorption Water Treatment

Water containing dissolved salts of calcium and magnesium is called hard water. The hard water is generally softened by using ion-exchange resins. The use of these resins is based on the principles of selective Adsorption from the solution. These resins adsorb the hardness producing ions from the hard water and make it soft. Similarly, in the permit process, the zeolite used adsorbs calcium ion \(\left( {{\rm{C}}{{\rm{a}}^{2 + }}} \right)\) and magnesium ions \(\left( {{\rm{M}}{{\rm{g}}^{2 + }}} \right)\) present in the hard water and makes it soft.

5. Application of Adsorption Chromatography

The selective Adsorption of certain substances from a solution by a particular solid adsorbent is used to separate the component of the mixture in chromatographic analysis.
For example, in column chromatography, a long and wide vertical tube is filled with a suitable adsorbent, and the solution of the mixture is poured from the top and then collected one by one from the bottom.

application of adsorption chromatography

6. Application of Adsorption In Precipitation Titration Using Adsorption Indicators

Various dyes such as fluorescein, eosin, etc., are used as adsorption indicators in the precipitation titrations.
For example, \({\rm{KBr}}\) can be titrated against \({\rm{AgN}}{{\rm{O}}_3}\) using eosin as an indicator. After the completion of the titration, the ions produced by the dye in the solution get adsorbed onto the precipitates of silver bromide and undergo a colour change.

7. Application of Adsorption For Creating Partial Vacuum

The phenomenon of adsorption of gases on solids, particularly at low temperatures, is used for creating a partial vacuum. The vessel to be evacuated is connected to a narrow container containing activated charcoal dipped into liquid nitrogen. The extend of the Adsorption of gases on solid is very high at low temperatures. So, the gases present in the vessel are adsorbed by the animal charcoal, and a partial vacuum is created.

8. Application of Adsorption In Production and Preserving High Vacuum

The remaining traces of air can be adsorbed from a vessel already evacuated by a vacuum pump to produce a high vacuum.
For example, in Dewar flasks, activated charcoal or silica gel is usually placed between the walls of the flask. If any gas enters into the annular space, it gets absorbed, and thus, the vacuum remains preserved.

9. Application of Adsorption In Heterogeneous Catalysis

Most heterogeneous catalytic reactions proceed through the Adsorption of the gaseous reactant on the solid catalyst. The solid catalyst adsorbs the gaseous reactants on its surface. This increases the concentration of the reactants at the surface of the catalyst, and consequently, the rate of reaction increases
For example, finely powdered nickel \(\left( {{\rm{Ni}}} \right)\) is used for the hydrogenation of oil, finely divided vanadium pentoxide \(\left( {{{\rm{V}}_2}{{\rm{O}}_5}} \right)\) is used in the contact process for the manufacture of sulphuric acid, platinum \(\left( {{\rm{Pt}}} \right)\) and palladium \(\left( {{\rm{Pd}}} \right)\) is used in many industrial processes as a catalyst, etc.

10. Application of Adsorption For Desiccation or Dehumidification

Certain substances have a strong tendency to absorb water. These substances can be used to reduce or remove water vapours present in the air. Silica gel is used for dehumidification in electronic equipment. Silica gel is the most commonly used dehumidifier, i.e., to absorb humidity or moisture from the air.

11. Application of Adsorption In the Separation of Noble Gases

A mixture of noble gases is usually separated by adsorbing them on activated charcoal. The separation is based on the difference in the degree of Adsorption of these gases by charcoal.

12. Application of Adsorption In the Pharmaceutical Industry

Some drugs can absorb the germs on them and hence kill them and save us from the diseases. Activated charcoal, magnesium oxide, tannic acid, etc., are used for the absorption of poisonous and toxic substances. Adsorption is also used in vitamin B1 preparation, bacterial filtration, pharmaceutical adsorption, etc.

13. Application of Adsorption In Froth Floatation Process

The froth floatation process generally used for concentrating sulfide ores makes use of the adsorption process. When sulfide ore is shaken with pine oil and water, the ore particles are adsorbed on the froth that floats and gangue particles like silica, earthy material, etc., settle down in the tank. The separated froth contains sulfide ore.

14. Application of Adsorption In Clarification of Sugar

Sugar is decolourized by treating sugar solution with charcoal powder. The latter absorbs the undesirable colours present.

15. Application of Adsorption In the Paint Industry

The dissolved gases in paints are removed using suitable adsorbents during the manufacture of paints. Dissolved gases do not adhere well to the surface to be painted and thus show poor covering power. Wetting agents are used to remove the gaseous, liquid, or solid films on the paint’s surface. The spirit is a commonly used wetting agent in furniture polishing.

16. Application of Adsorption For Recovery from Industrial Wastes

Components of a mixture can be separated, making the use of the difference in the absorption power of the various components of any mixture. Several valuable recoveries are made from industrial wastes by employing the principles of Adsorption.

17. Application of Adsorption In Water Conservation

In countries like Australia where there is acute scarcity of water during summer, a layer of stearic acid is sprayed over the lakes and other water reservoirs. It is adsorbed on the surface of the water, thereby minimizing the loss of water by evaporation.

Summary

 In this article, you have learned about the meaning of Adsorption and its applications in the pharmaceutical industry, chromatography, industrial process, catalysis, etc. This knowledge will be useful in the application and identification of the adsorption process in your daily life.

FAQs on Application of Adsorption Chromatography

Following are some of the frequently asked questions on application of adsorption chromatography which students must know:

Q.3. What are the types of adsorptions?
Ans
: Depending on the nature of the force existing between the adsorbate and adsorbents molecule, the absorption is classified into two types, i.e., physisorption (physical Adsorption) and chemisorption (chemical adsorption).

We hope this detailed article on applications of adsorption is helpful to you. If you have any queries on this article, ping us through the comment box below and we will get back to you as soon as possible.

Take Mock Tests related to Adsorption & Absorption