Ion exchange chromatography may be defined as a reversible reaction in which free mobile ions of a solids called ion exchange are exchanged for different ions of similar charge present in solution.....................................................................

1. Ion Exchange
Chromatography
Presented By : Zainab Arshad
BS Hons, Environmental Sciences
University Of Gujrat, Pakistan

2. Chromatography
• Chromatography (from Greek
chroma "colour and graphein "to
write") is the collective term for a
set of laboratory techniques for
the separation of mixtures. The
mixture is dissolved in a fluid
called the mobile phase, which
carries it through a structure
holding another material called
the stationary phase. The various
constituents of the mixture travel
at different speeds, causing them
to separate. The separation is
based on differential partitioning
between the mobile and stationary
phases.

3. PRINCIPLES
• Chromatography usually consists
of mobile phase and stationary
phase.
• The mobile phase refers to the
mixture of substances to be
separated dissolved in a liquid or
a gas.
• The stationary phase is a porous
solid matrix through which the
sample contained in the mobile
phase percolates.
• The interaction between the
mobile phase and the stationary
phase results in the separation of
the compound from the mixture.

4. Types of
Chromatography
There are following types of
Chromatography
Paper Chromatography
Thin Layer
Chromatography(TLC)
Gel Chromatography
Column Chromatography
Ion Exchange Chromatography
Gel Filtration Chromatography
Gas Liquid Chromatography
Affinity Chromatography

5. Ion Exchange
Chromatography
• Ion exchange chromatography may be defined
as a reversible reaction in which free mobile
ions of a solids called ion exchange are
exchanged for different ions of similar charge
present in solution
• EX:- insoluble organic polymer in to which
charged group is introduced.

6. Ion exchange chromatography -- is a separation based
on charge
Used for almost any kind of charged molecules ---
large proteins, small nucleotides and amino acids
Ion-exchange chromatography preserves analyte
molecules on the column based on ionic interactions
Mobile phase – buffer, pH and salt concentration---
opposite charged solute ions attracted to the stationary
phage by electrostatic force
Stationary phase– resin is used to covalently attach
anions or cations onto it

7. Common properties of all
ion exchangers
• They are almost insoluble in water and inorganic
solvents such as benzene, carbon tetrachloride,
ether etc.,
• They are complex in nature, i.e., infect they are
polymeric.
• They have active or counter ions.

8. Principle
• The principle involved in the chromatography is the
attraction between oppositely charged particles.
• Many biological materials such as amino acids and
proteins, have ion sable groups and they carry a net
positive or negative charge can be utilized in separating
mixtures of such compounds.
• The net charge of such compounds is dependent on their
pKa and pH of the solution.

10. Cation exchange chromatography retains positively
charged cations because the stationary phase displays a
negatively charged functional group:
Anion exchange chromatography retains anions using positively
charged functional group:
.

12. Ion Exchange Mechanism
Diffusion of the ion to the exchanger surface.
Diffusion of the ion through the matrix surface of the
exchanger to the exchange site.
Exchange of the ions at the exchange site.
Cation exchanger
Anion exchanger

13. Diffusion of the exchanged ion through the exchanger to
the surface.
Selective desorption by the eluant and diffusion of the
molecule in to the external solution.
Cation Exchangers
A cation exchanger is a high molecular weight, cross
linked polymer having sulphonyl, carboxylic, phenolic
etc., groups as an integral part of the resin and an
equivalent amount of cations.

14. Thus, a cation exchanger is nothing but a polymeric anion
to which active cations are attached .
In these cation exchangers the hydrogen ions are mobile
and exchangeable with other cations
When cation exchanger is kept in a solution of salt, some of
the H+ ions of the resin enter the solution and in equivalent
amount of the cations of the salt get attached to resin.

15. The resin having sodium ions produced in the above reaction, can
exchange these ions with other cations.
Some commercially available cation exchangers:

16. Anion Exchangers
An anion exchanger is a polymer having amine or quaternary
ammonium groups as integral parts of the resin and an equivalent
amount of anions such as Cl-, OH- ions etc.
These ions are mobile and exchangeable.

17. Commercially available anion exchangers:

18. Regeneration
• anion exchanges are generally supplied in the form of
• Salts ,amines, in particular ,are stable only in this form.
• Cation exchanges can be converted in to the H+ form
by treatment with aqueous acid followed by washing
the ammonium base having hydroxyl group from the
strongly basic anion exchanger on treatment with
sodium hydroxide while the weakly basic anionic
exchanges are converted in to free amines

19. Applications
• Separation of similar ion from one
another.
• Removal of interfering radicals.
• Softening of hard water.
• Complete demineralization of water.
• Separation of lanthanides.
• Separation of actinides.
• Separation of amino acids.
• Separation of sugars.

20. REFERENC
E
https://www.harvardapparat
us.com/downloads/Ion%20E
xchange%20Chroma%20Spi
nColumn%20Guide.pdf.
Instrumental analysis by
Gurdeep R. Chatwal
Instrumental analysis by
Skoog.