Extraction chromatography

Dr.S. H. Burungale

1. Extraction Chromatography
Dr. S. H. Burungale

2. CONTENTS
Introduction to chromatography
Definition of Chromatography
Types of column chromatography
Theory of chromatography
Practical considerations in column
chromatography
Factors affecting efficiency of a column
Applications

3. INTRODUCTION
Chromatographydesignatesthegenericnamecollectively
assignedtohostdivergentseparationtechniquesthathavebeen
dulyrecognizedrightfromtheearly1900stilldate.
MikhailTswett,aRussianBotanistfirstandforemostcoined
theterminology“Chromatography”
In1906heperformedinvestigationsofplantpigments,byusing
adsorptionchromatographyandhassuccessfulseparatedbyusing
leafpigments
Theterm“Chromatography"emergedfromGreekwords:
‘Chroma’meansColourand‘Graphein’means‘towrite’.

4. DEFINITION
Chromatographyisatechniqueemployedfor
separationofthecomponentsofmixtureby
continuousdistributionofthecomponentsbetween
twophases.
Ettre(1993)vehementlyrecommendedthe
IUPACdefinitionofchromatographywhich
definesitas‘Aphysicaltechniqueofseparation
whereinthecomponentsrequiredtobeseparated
betweenthetwophases,oneofwhichbeing
‘stationary’(stationaryphase),whiletheother
(mobilephase)thatmovesinadefinitedirection’

9. COLUMNADSORPTIONCHROMATOGRAPHY
TheprincipleinvolvedinthistechniqueisAdsorption.
Whenamixtureofcompounds(adsorbate)dissolvedinthe
mobilephase(eluent)movesthroughacolumnofstationary
phase(adsorbent)theytravelaccordingtotherelative
affinitiestowardsstationaryphase.
Thecompoundwhichhasmoreaffinitytowardsstationary
phasetravelsslowerandthecompoundwhichhaslesser
affinitytowardsstationaryphasetravelsfaster.
Inthisway,thecompoundsareseparated.

11. COLUMN PARTITION CHROMATOGRAPHY
Theprincipleinvolvedinthistechniqueispartition.Whentwo
immiscibleliquidsarepresent,amixtureofsoluteswillbedistributed
accordingtotheirpartitionco-efficients.
Whenthemixtureofcompoundsdissolvedinthemobilephaseand
passedthroughacolumnofliquidstationaryphase,thecomponent
whichismoresolubleinstationaryphasetravelsslowerandthe
componentthatismoresolubleinmobilephasetravelsfaster.
Thestationaryphaseusedcannotbealiquid.Sothatasolidsupportis
usedoverwhichathinfilmorcoatingofaliquidismadewhichactsasa
stationaryphase.

16. STATIONARY PHASE
(ADSORBENT)
Agoodnumberofsolidcompoundsbelongingto
either‘organic’or‘inorganic’domainarebeing
extensivelyemployedasadsorbentsincolumn
chromatography.
Examples:1.Organicsubstances:Carbon,Starch,
Cellulose2.Inorganicsubstances:Alumina,Silicagel,
Fuller’searth,Kiesulgur

17. 17
Silica gel
Alumina
Cellulose
Kieselguhr
SilicaGel:Itisslightlyacidicinnature.Thesilanolgps(Si-OH)ofsilica
gelrepresentadsorptionactivesurfacecenterswhicharecapableto
interactwithsolutemolecules.Theabilityofthesilanolgps.toreact
chemicallywithappropriatereagentsisusedforcontrolledsurface
modification
Structure of Silica Gel
Si-OH Silanol Group; Si-O-Si Siloxane Group
Silanol Groups represent adsorption-active surface centre

18. Theoretical Plate
LC -liquid chromatography
packed columns
Silica
beads
Stationary
phase
liquid (mobile phase)

19. IonicRecognitionExtractantbasedresin
–AnalyteretentionrelatedtochargeandionicradiiNeutraland
AnionicExtractantbasedresin
–Analytesaredirectlyhydrogeniondependant,although
anionicextractantbasedresinstendtoshowreduced
analyteuptakeastheacidcompetes
AcidicExtractantbasedresin
–Analyteretentionisinversehydrogeniondependant
Anionic Extractant

20. General requirements:
Particle size and geometry: uniform size& spherical
shape. (60-200μ)
High mechanical stability
Inert and should not react with the solute or other
compounds
Insoluble in the solvents or mobile phases used
It should allow free flow of mobile phase
Useful for separating a wide variety of compounds
Freely available and inexpensive.

21. Synthesis of Stationary phase
ThechromatographicColumnwasmadeofaborosilicateglass
tubewith8mmbore,30cmlengthandfilledglasswoolatthe
bottom.
0.1MTOPOsolutionwaspreparedbydissolving1.94gof
reagentin100mLoftoluene.Silicagel(60to120Mesh)was
driedat1200cfor2to3hours.Andstoredinadesiccators.
SomeoftheSilicagelwaspackedinaUtubethroughwhich
waspassedastreamofdrynitrogengasbubbledthrough
containinga20mlDimethyldichlorosilaneDMCS.Thepassaes
ofDMCSvapourwascontunedfor3to4H.Thesilicagelwas
thenwashedwithanhydrousmethanolanddried.

22. A5gportionofthesilanedsilicagelwassoakedina5ml
of0.1MTOPOintoluene
For24h.Thesolventwasthenevaporatedtillthegelwas
nearlydryAslurryofcoatedsilicagelindistilledwater
waspreparedbycentrifugationat2000rpmandllastly
coatedsilicagelwaspackedintochromatographiccolumn
togiveaheightof6cm.thebedwascoveredwithglass
wool.

53. 1. Chromatography is a physical method that is used to separate and
analyse __________
a) Simple mixtures
b) Complex mixtures
c) Viscous mixtures
d) Metals
Answer:b
Explanation:Chromatography is a physical method that is used to
separate complex mixtures. The mixture of different components is
flushed through the system at different rates.
2. In which type of chromatography, the stationary phase held in a
narrow tube and the mobile phase is forced through it under
pressure?
a) Column chromatography
b) Planar chromatography
c) Liquid chromatography
d) Gas chromatography

54. Answer:a
Explanation:In Column chromatography, the stationary phase held in a
narrow tube and the mobile phase is forced through it under pressure. It
is carried out in a long glass column having a stop-cock near the bottom.
3. In chromatography, the stationary phase can be ___________
supported on a solid.
a) Solid or liquid
b) Liquid or gas
c) Solid only
d) Liquid only
Answer:a
Explanation:In chromatography, there are two phases namely,
stationary phase and mobile phase. The stationary phase can be solid or
liquid supported on a solid.

55. 4. In chromatography, which of the following can the mobile phase be made of?
a) Solid or liquid
b) Liquid or gas
c) Gas only
d) Liquid only
Answer:b
Explanation:In chromatography, the mobile phase can be composed of liquid or gas. It
cannot be a solid material.
5. Which of the following cannot be used as adsorbent in Column adsorption
chromatography?
a) Magnesium oxide
b) Silica gel
c) Activated alumina
d) Potassium permanganate
Answer:d
Explanation:The given options are all examples of adsorbents in Column adsorption
except potassium permanganate. Some other adsorbents are starch and chromatographic
purified siliceous earth

56. Thank
You