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Teknik BioseparasiDina Wahyu
Genap/ Maret 2014
OutlineChemical Reaction Engineering
Pendahuluanmempelajari ruang lingkup teknik bioseparasi dan teknik “cel disruption”
Teknik Pemisahan Secara Fisika 2Mempelajari teknik pemisahan sedimentasi
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2
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Teknik Pemisahan Secara Fisika 1Mempelajari teknik sentrifugasi pada bioseparasi
Koagulasi dan flokulasi Mengetahui teknik pemisahan dengan cara koagulasi dan flokulasi
Teknik Pemisahan Secara Fisika 3 Mempelajari teknik filtrasi pada bioseparasi
Adsorpsi Proses adsorpsi pada cairan dan gas, serta pengetahuan bahan adsorpsi
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Adsorpsi 2Kinetika Adsorpsi, Isotherm Adsorption7
Methods of PurificationDescribe methods of separation for the components of the following types of mistures:
(i) solid-solid(ii) solid-liquid(iii) liquid-liquid(miscible)
Techniques to be covered for separations and purification include:
(i) Use of a suitable solvent, filtration and crystallization or evaporation
(ii) Distillation and fractional distillation(iii) Paper chromatography
Pure Substances & MixturesA pure substance contains only one type of
substance, and is not mixed with any other substance.
Are the following pure substances or mixtures?Are the following pure substances or mixtures?• Clean tap water• 100% orange juice• Distilled water
mixture
mixture
Pure substance
Methods of PurificationSome terms :
• Solute - the solid that dissolves• Solvent - the liquid that does the dissolving• Solution - solid + solvent• Residue - the insoluble solid trapped in the filter • Residue - the insoluble solid trapped in the filter
paper• Filtrate - the liquid that passes through the filter
paper• Sublimate - the condensed solid produced during
sublimation
Methods of PurificationThe particular method used for separating
any given mixture depends on the nature (eg. solubility, physical state) of its constituents.
Filtration• Used to separate a solid from a liquid in
which the solid is insoluble
residuemixture of solid and
liquid
filter paper
filter funnel
residueliquid
filtrate
Principle of Filtration
• The separation works only if the particles concerned
are of different sizes, such as larger particles of an
insoluble solid and smaller particles of a liquid or
solution.solution.
Principle of Filtration
The filter material acts as a sieve which allows
the smaller particles to pass through and
keeps the bigger particles behind.
Principle of Filtration
Can a mixture of common salt and water
be separated by filtration? Why?
Filtration - large scale use
• Sand filters used in water treatment plants to
remove solid impurities
• Dissolved substances and bacteria will not be
removed
Decanting• Separates an insoluble solid from a liquid
• liquid is carefully poured away from the solid
which is usually heavier and settles at the
bottom of the container. bottom of the container.
Evaporation (Heating )to Dryness
• used to recover a soluble solid from its solution
• Only for solids that will NOT decompose on heating.heating.
• Eg. sodium chloride (common salt) from salt solution
Crystallisation• used to recover a soluble solid from its solution• for solids that decompose on heating• Eg. Copper(II) sulphate and most other salts
Steps :• The solution is heated (evaporated) to saturation • The solution is heated (evaporated) to saturation point OR ‘heated to remove most of the solvent’
• The saturated solution is left to cool; crystals are formed.
• The crystals are removed by filtration. To purify the crystals, they can then be washed with cold distilled water and dried between filter papers.
Crystallisation - the Principle behind
• Substances are usually more soluble in hot water than cold water eg. more copper(II) sulphate will dissolve in water at 80ºC than at 30 ºC.
• When the hot saturated solution is cooled, the • When the hot saturated solution is cooled, the cooled solution is unable to hold as much solute as when it was hot. The extra solute that cannot remain dissolved appears as crystals.
Solubility & Crystallisation
Solubility data for NH4Cl in grams/100 mL H2O • 30oC - 41.4 g • 50oC - 50.4 g • 70oC - 60.2 g • 90oC - 71.3 g • 90oC - 71.3 g
If the water was heated to 90°C, how much of the solute will be able to dissolve?If this hot solution is then cooled to 30 °C, how much solute can the water contain now?Hence what is the mass of crystals you would expect to obtain?
Separating a mixture of solids
Method used depends on the nature of the solids :-(1) If the mixture of solids behave differently in a
particular solvent , that is, one component is soluble in it while the other is insoluble…
carefully choose a solvent that will dissolve only one of the solids
Egs. common salt and sand; naphthalene and sand
Use water as solvent
Use methylated spirits as solvent
Separating a mixture of solids
Basic Steps :
Dissolution Filtration
Evaporation to dryness
OR
Crystallisation
OR
Separating a mixture of solids
(2) Sublimationused when one of the
solid sublimesEg. Eg.
• mixture of iodine + copper;
• mixture of ammonium chloride +sodium chloride
Separating a mixture of solids
(3) Other methods :
• make use of the special properties of the substance
Eg. mixture of iron filings and sulphur …. Eg. mixture of iron filings and sulphur …. …use a magnet
• Bring a magnet to the mixture.
• The iron filings will be attracted to the magnet while the sulphur will be left behind.
Separating the Solvent from the Solution
solute solvent
Crystallisation
Evaporation to dryness
Distillation
solute solvent
solution
Simple Distillation• Some Terms Used :
• Distillate - the liquid that distils over• Miscible liquids - liquids that mix completelyto form a single layer
• Immiscible liquids - liquids that do not mix• Immiscible liquids - liquids that do not mix• A solvent can be separated from a solution and
collected by simple distillation.
Principle of Distillation
A liquid boils and turns into vapour at its
boiling point.
When the vapour is condensed, the (pure) liquid
is obtained again.
Simple Distillation
flask
thermometer
2. .. vapourise. The vapour rises up the flask
3. the condenser is cold, sothe vapour condenses to liquid water.
flask
sea water
1. Solution is heated, causing the solvent to …
condenser
distillate
Boiling chips4. Pure water drips into the beaker. It is distilled water.
Simple Distillation
flask
thermometer
Water outflask
sea water condenser
Boiling chips
Water in
To maintain even boiling, with not too much bumping
Liebig Condenser
Vapour entersCondensed vapour in liquid
form (distillate) leaves
Cold water in
Water out
Direction of water flow
Water flows in anti-current to the flow of vapour.
Liebig Condenser
Vapour entersCondensed vapour in liquid
form (distillate) leaves
Cold water in
Water out
Direction of water flow
This is to make sure the coldest part of the condenser is just before the vapour escapes.
Simple DistillationSimple distillation can be used to obtain
• from salt solution• from copper(II) sulphate solution• from a solution of sugar in ether
waterwater
ether
Note : The liquid that distils over is called the distillate . The solid that remains in the flask is called the residue .
Simple Distillation
Qns. : Where is the thermometer placed? What is the reason for this?
thermometer
flask
sea water condenser
distillate
Boiling chips
Simple DistillationThermometer placed at the side arm of the flask so
that it records the temperature of the vapour as it enters the condenser.
thermometer
flask
sea water condenser
distillate
Boiling chips
Separating miscible liquids -Fractional distillation
• miscible liquids can only be separated by fractional distillation if they have different boiling points . different boiling points .
• Eg. mixture of ethanol and water.
Separating miscible liquids -Fractional distillation
thermometer
Water out
condenser
Fractionating column
flask
mixture of ethanol and water
Water indistillate
Boiling chips
Separating miscible liquids -Fractional distillation2. The fractionating column is
packed with glass beads to increase its surface area. Vaporisation followed by
condensation takes place many times as the vapour is
3. Eventually, the liquid with the lower boiling point reaches the top and distils over.
1. When heated, the liquid with the lowerboiling point will vaporize more readily.
many times as the vapour is swept upwards.
Separating miscible liquids -Fractional distillation
4. The temperature stays constant at 78°C.
When all the ethanol has distilled over, the
temperature reading rises above 78°C. At
5. The receiver is changed to collect each distillate separately.
rises above 78°C. At 100°C, water starts to
distil over.
Separating miscible liquids -Fractional distillation
Sketch a graph of temperature versus time to show the changes in temperature readings throughout the distillation.
temperature
time
78°C
100°C
Separating miscible liquids -Fractional distillation
Note : • The glass beads in the
fractionating column provides a large surface area so that condensation occurs more
glass bead
s
condensation occurs more readily.
• The liquid with the lowerboiling point distils over first, followed by the liquid with the next higher boiling point.
Separating miscible liquids -Fractional distillation
Note : • If the liquids in the mixture
have the same boiling point, fractional distillation is not possible.
glass bead
s
possible.• If the difference in boiling point
is great, fractional distillation occurs readily.
Fractional distillation -applications
• Fractional distillation can be used to separate :-• nitrogen and oxygen from liquid air• nitrogen and oxygen from liquid air
• the components of crude oil
• ethanol from fermented liquor
Fractional distillation of crude oil
Separating immiscible liquids
• A separating funnel can be used to separate two immiscible liquids. • Eg. water and petrol.• Eg. water and petrol.
• This method can be used to separate :• a mixture of petrol and
water• engine oil and water
The main points so far…Mixtures
solid + solidsolid + liquid
(Solid INSOLUBLE in (Solid INSOLUBLE in liquid)liquid)
liquid + liquid
Residue(solid)
Filtrate(liquid)
Filtration
liquid)liquid)
The main points so far…Mixtures
solid + solidsolid + liquid
(Solid SOLUBLE (Solid SOLUBLE in liquid)in liquid)
liquid + liquid
Residue
(solid/ solute)
Distillate
(liquid/ solvent)
Simple Distillation
in liquid)in liquid)
The main points so far…Mixtures
solid + solid
solid + solution Difference in
solubility?
YES
liquid + liquid
Residue(insoluble
solid)
Filtrate(solution)
Filtration
solubility?Add suitable solvent
CrystallisationCrystals(soluble
solid)
The main points so far…Mixtures
solid + solid
solid + solution Difference in
solubility?
YES
liquid + liquid
Filtration
solubility?Add suitable solvent
NO
Other physical difference?
Sublimation
Using magnetEgs.
Crystallisation
The main points so far…Mixtures
miscible liquids
(different boiling
immiscible liquids
liquid + liquid
Fractional distillation
boiling pts.)
liquids
Separating funnel
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