An Introduction to

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An Introduction to OLEOCHEMISTRY
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Process Schedule
natural oils fats
crude glycerine
fatty acids
splitting
glycerine pretreatment
separation
oleic acids
stearic acids
distillation/hardening
glycerine refining
Ethanoic (acetic) acid
glycerine
Fatty (carboxylic) acids
alcohols
stearine (saturated) acids
Oleine (unsaturated acids)
esterification
esterification
esters
esters
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• What is an Oleochemical?

This is a chemical derived from natural,
biodegradable oils and fats with vegetable or
animal sources. Versatility makes them ideal for
high-performance speciality products in areas as
diverse as sweets, cakes, diabetic foods, engine
lubricants, engineering plastics, cosmetics,
cleaning and pharmaceutical products. The source
of the raw material will impact the applications
it can be used in. The raw material we will
consider is tallow.
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• What is Tallow?

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Tallow is a natural product from the animal
rendering process, it is referred to as "fat it
is a tri-glyceride, this means that it is made up
of one part glycerine and three parts fatty
(carboxylic) acid. Tallow is made up of carbon,
hydrogen and oxygen, its structure can be
represented as follows
Fatty Acid
Glycerine
Fatty Acid
Fatty Acid
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• or...Technically Speaking!

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O HCH O C Ra
O HC O C Rb
O HCH O C Rc
TALLOW
C Carbon H Hydrogen O Oxygen
R represents a chain made up of Carbon and
Hydrogen. Ra, Rb and Rc can contain the same or
different numbers of carbons.
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Tallow Splitting
Water
Fatty Acid
Steam
Tallow
Glycerine Water
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• SPLITTING

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The tallow molecule is SPLIT to produce glycerine
and fatty acids by the SPLITTING PROCESS. Water
is used in the form of high pressure steam to
split the tallow and give two products, a weak
glycerine solution known as SWEETWATER, and the
CRUDE FATTY ACIDS. The water molecule, H-OH (or
H2O), also splits during this process. The
following slide illustrates this.
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6

• SPLITTING

Tallow "split" here by water, as steam, H-OH
(H2O).
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• There are two products from the splitting
  process
• 1. SWEETWATER

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Sweetwater is a weak solution of glycerine in
water. Glycerine is very soluble in water, even
at room temperature. The sweetwater is first
dried (removes water) and purified by refinery
and distillation. It is a colourless, viscous
liquid at room temperature.
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• GLYCERINE

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Glycerine has the chemical structure shown below
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8

• 2. CRUDE FATTY ACIDS

The crude fatty acids are a mixture of saturated
and unsaturated fatty acids and processed in a
number of ways, Involving Distillation- to
remove any un-split material and colour bodies,
these form the distillation residues and are very
dark and smelly! Separation- to separate
saturated and unsaturated fatty
acids Hydrogenation- to completely remove any
unsaturated fatty acids by saturating them. This
is also called Hardening.
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9

• What is FATTY ACID?

The structure of a fatty acid can be represented
as
OXYGEN
O HO C R
HYDROGEN
What is this?
HYDROXYL GROUP
CARBON
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10

• The "R" Group.

The R group is a chain made up of carbon and
hydrogen. The three fatty acid molecules of
tallow each contain a different R group. This
explains why we get a mixture of fatty acids when
we split tallow. The R group defines the
properties of the fatty acid. The fatty acid
chains can be "saturated" or "unsaturated". This
refers to whether or not the fatty acid could
hold any more hydrogen in the R chain.
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• The "R" Group.

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The WET SEPARATION process actually separates
these two types to produce "stearine" (saturated)
and "oleine" (unsaturated) mixtures of fatty acid
chain lengths. Saturated fatty acids are solid
at room temperature. The process to convert
unsaturated fatty acid to saturated is called
HYDROGENATION but is referred to as HARDENING
since this is what actually happens.
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• Types of R Group

A saturated Chain
An Unsaturated Chain
H H H H C C C H
H H H
H H H C C C H H H
LIQUID
SOLID
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• Naming Fatty Acids

A Fatty Acid is named according to how many
Carbons it contains. The following examples
explain the naming procedure but are not
commercially available through Unichema
International. The following would be called a
C3 fatty acid (propanoic acid)
O H H HO C C C H
H H
2
3
1
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14

• Naming Fatty Acids

Using the same method this fatty acid would be
called C5 (pentanoic acid)
O H H H H HO C C C C C H
H H H H
2
3
4
5
1
18
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• Naming Fatty Acids

We can extend this method to include the number
of unsaturated bonds, for example this fatty acid
is known as C5.1. Meaning there are 5 Carbon
atoms and one unsaturated bond.
O H H H HO C C C C C H
H H H
1
2
3
4
5
1
This fatty (carboxylic acid) doesnt actually
exist naturally!
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• A SATURATED FATTY ACID
• STEARIC (Octadecanoic) ACID
• (A major component in "Stearine")

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O H H H H H H H H H H H H H H H H H HO C
H H H H H H H H H H H H H H H H H H
C C C C C C C C C C C C C C C C C
Using the system then this is called a C18 fatty
acid. It is a white, hard, solid.
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• AN UNSATURATED FATTY ACID
• OLEIC (cis-9-octadecaonoic) ACID
• (The major component in "oleine")

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O H H H H H H H H H H H H H H H H
HO C H
H H H H H H H H H H H H H H H H
C C C C C C C C C C C C C C C C C
unsaturated bond
This is known as C18.1 fatty acid. It is an amber
liquid.
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• ESTERIFICATION

Alcohol Acid ? Ester Water
The reaction of fatty acid with an alcohol
produces ester and water. The esters can be
separated from the water because they have low
solubility in it. Esters can be produced under
conditions of low or high temperature and the
crude product is distilled, bleached and
deodorised as appropriate before a pure ester is
produced.
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• ESTERIFICATION
• (to produce Glyceryl Triethanoate (Glyceryl
  Triacetate)

Ethanoic (Acetic) Acid
H-OH
Glycerine
Ethanoic (Acetic) Acid
H-OH
Ethanoic (Acetic) Acid
H-OH
Glycerine 3 Ethanoic Acid ? Glyceryl
Triethanoate 3 Water
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• ESTERIFICATION
• (to produce Glyceryl TriOleate)

Oleic Acid
H-OH
Glycerine
Oleic Acid
H-OH
Oleic Acid
H-OH
Glyceryl Trioleate is an amber liquid. It is an
ester. Note the IUPAC name for Oleic Acid is
cis-9-octadecanoic acid.
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Process Schedule
natural oils fats
crude glycerine
fatty acids
splitting
glycerine pretreatment
separation
oleic acids
stearic acids
distillation/hardening
glycerine refining
Ethanoic (acetic) acid
glycerine
Fatty (carboxylic) acids
alcohols
stearine (saturated) acids
Oleine (unsaturated acids)
esterification
esterification
esters
esters
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Worksheet 1
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Clues!

• Raw materials and residues are more coloured
• Saturated fatty acids are used in candles
• Raw materials have an unpleasant odour.
• Unsaturated fatty acids are liquid
• Esters can be colourless or coloured dependant on
  the alcohol and acid used to make them
• Esters are less acidic than fatty acids
• Fatty acids are used to make soaps
• Sweet/ caramel smelling esters are used in
  ice-cream and diabetic foods

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Worksheet 1 (in progress!)
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Problems with sample 3 and 9?

• What is the main difference between a fatty acid
  and an ester that youve discovered today?
• How might we use this to find out which sample is
  the fatty acid, and which is the ester?
• This needs to be a fair test, what should we
  consider?

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Problems with sample 3 and 9?

• What is the main difference between a fatty acid
  and an ester that youve discovered today?
• acidity
• How might we use this to find out which sample is
  the fatty acid, and which is the ester?
• Remember- ACID ALKALI NEUTRAL
• Use pH paper?
• Use an indicator?
• Make a solution and see how much alkali is needed
  to neutralise it.
• What solvent should we use to make the solution?

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Problems with sample 3 and 9?

• This needs to be a fair test, what should we
  consider?
• Our solvent should be neutral
• We should use the same amount of sample
• We should use the same concentration of alkali
• If we get a higher volume of alkali needed to
  reach neutral, does that mean the sample is more
  or less acidic?
• O.K. LETs DO IT!

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Acidity experimental results
EXTRA QUESTION- CAN YOU WRITE THE WORD EQUATION
FOR THE REACTION BETWEEN OLEINE AND SODIUM
HYDROXIDE?
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Worksheet 1 (still in progress!)
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Problems with sample 2 and 6?

• What is the main difference between glycerine and
  an ester that youve discovered today?
• How might we use this to find out which sample is
  glycerine, and which is the ester?
• This needs to be a fair test, what should we
  consider?

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Problems with sample 2 and 6?

• What is the main difference between glycerine and
  an ester that youve discovered today?
• Glycerine is far more water soluble than an
  ester.
• How might we use this to find out which sample is
  glycerine, and which is the ester?
• Add the sample to water and see if it is soluble.
• This needs to be a fair test, what should we
  consider?
• The water should be at the same temperature
• We should add the same weight of sample

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Water Solubility Experimental results
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Worksheet 1 (the final answers)
SINCE acid alkali ? salt water this gives
Oleic acid sodium hydroxide ? sodium oleate
water.
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A quick word on Catalysis
Nickel is used to catalyse the hydrogenation
reaction. Look at the samples provided, are the
changes to the catalyst that you can see physical
or chemical?
Ni
Unsaturated fatty acids hydrogen ? saturated
fatty acids
What practical problems do you think there would
be in reclaiming the nickel?