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HERMIN HARDYANTI UTAMI (111 304 0202)
CHEMISTRY DEPARTMENT
MATHEMATIC AND SCIENCE
FACULTY
STATE UNIVERSITY OF MAKASSAR
2012
RATIFICATION PAGE
The complete report of Organic Chemistry II with the title of “Caffeine
Extraction” which made by :
Name : Hermin Hardyanti Utami
ID : 111 304 0202
Group : VII
Class : ICP B
Have been checked by assistant and assistant coordinator. So, this report is
accepted.
Makkassar, December 2012
Assistant Coordinator
Fandi Ahmad, S.Pd.
Assistant
Muh. Jufri
Known By,
Responsibility Lecturer
Dra. Hj. Ramdani, M.Si.
A. Title of Experiment
Caffeine Extraction
B. Purpose of Experiment
Known continue extraction with heat intermediately
C. Preview of Literature
In this course in term “extraction refers to the process where by a
component in a mixtures is transferred into another solvent phase. The operation
involves shaking an immiscible pair of liquids, where by a solute passes from a
liquid to the other. Commonly one of the liquids will be an aqueous (water)
solution an the other an organic solvent (e.g diethyl ether or CH2Cl2) or a solution
involving an organic solvent.
Before using the separating funnel, apply a thin coat of grease or when
dicholoromethane is used as solvent a film of water to glass tap (DO NOT grease
teflon taps). Check for leaks by adding a small volume at the solvent to used to
the separating funnel with the tap inserted and closed (Anshori, 2005: 1).
The ease with which amines are extracted into aqueous acid, combined
with their regeneration on treatment with base, make it a simple matter to separate
amines from other plant materials and nitrogen containing natural producucts
were among the earliest organic compounds to be studied. Their basic properties
lead amines obtained from plants to be called alkaloids. The number of known
alkaloids excededs 5.000. They are special interest because most are characterized
by high level of biological activitity. Some examples include cocaine, consine,
and morphine.
Cocaine (a central nerveus
system stimulant obtained
from the laeves of the coca
plant).
N
O O
CH3
O
O
C 6H 5
CH3
Morphine ( an opium alkaloid, although it is an
excelent analgesic, its use is restricted because
of the potential for addiction. Heroin is the
diacitate ester of morphine)
(Carey, F.A. 2001: 869).
A natural product is a compound synthesized by a plant or animal.
Alkaloids are natural products that contain one or more nitrogens and are found in
leaves bark, roots or seeds of plant. Example include caffeinee (found in tea
leaves, coffee beans, and colanuts) and nicotine (found in tabacco leaves).
Morphine is an alkaloids obtained from opium the juice derived from a species of
puppy. Morphine is 50 times than aspirin as an analgesic but it is addictive and
suppresses respiration. Heroin is a synthetic compund that is made by acetylating
morphine.
N
NN
N
O
O
CH 3
CH 3
CH 3 N
N
CH 3
N
NCl
CH 3 O
C 6H 5
Caffeine Nicotine Valium
(Bruice, PY. 2003: 884).
Caffeinee (1, 3, 7-trimethylvathine) is an habitual substance present in a
wide variaty of a beverages and in chocolate-besed foods and it is also as drugs.
The antioxidant ability of caffeinee has been reported in contrast with its pro-
oxidant effects derived from its action mechanism such as systemic release of
catholamines. The aim of this work was to evaluate the effect of caffeinee on
exercise ovaditive stress, measuring plasma vitamins A, E, C, and melonaldhyde
(MDA) as markers of nonenzimatic antioxidant status and lipid peroxidation
respectively (Olcina. 2006: 621).
OH
OH
O
N
CH 3
H
Caffeinee (C8H10N4O2) is an alkaloid are bitter tasting natural nitrogen
containing compounds found in plants. The basic property of alkaloids comes
from lone pair of electrons found on at least one nitrogen. Alkaloids are often
found to have potent physiological activity. Some better known examples are
morhine, heroin, lysergic acid (LSD), cocain quine, strychine and nicotine. The
basic N in caffeine can be to increase or decrease is water solubility as a cation.
On the other hand if caffeinee is in the basic environment it takes the neutral form,
and is only some somewhat polar. Tea leaves contains tannins which are acidic as
well as a number of colored compounds and small amount of undercomposed
chlorophyll (soluble in chloromethane). The solubility in water is 2,2 mg/mL at
25°C, 180 mg/mL at 80°C, and 670 mg/mL at 100°C. Caffeinee can be aesily
extracted from tea bags. The procedure one would see to make a cup of tea –
simply “stepping” the tea with very hot water for about 7 minutes, extract most of
the caffeinee (Caballero, M.J. 2001).
D. Apparatus and Chemicals
1. Apparatus
a. Soxlet equipment, 1 piece
b. Breaker 250 mL, 1 piece
c. Buchner funnel, 1 piece
d. Beaker glass 1000 mL, 1 piece
e. Graduated cylinder 25 mL, 1 piece
f. Porceline cruicible, 3 pieces
g. Stative and clamp, 1 piece
h. Wash bottle, 1 piece
i. Bunsen, casa, tripot, 1 piece
j. Hot plate, 1 piece
k. Separating funnel, 1 piece
l. Erlenmeyer
m. Balance, 1 piece
n. Stirbar, 3 pieces
o. Rough and smooth cloth, 1 piece
p. Wood clamp and spoon, 1 piece
q. Boiling stone
2. Chemical
a. Tea
b. Ethanol 96%
c. MgO
d. Aluminium foil
e. Boiling water
f. H2SO4 dilute
g. Filtering paper
h. Aquadest
i. Matches
j. Ice cube
k. Chloroform (CHCl3)
l. Whatmann filtering paper
E. Work Procedure
1. As many as 50,00 grams of tea is balanced.
2. The tea is covered with filtering paper and it is bond.
3. The tea that already (after covered) is put in soxlet and the ethanol is
poured through the tea until a half of rounded flask.
4. The extraction process is done and it is waited until obtained 10th
circulation.
5. As many as 17,5 grams of MgO suspension solved in 150 mL H2O.
6. Let it dry when vapor.
7. Extract the powder with boiling water 250 mL (incruicible) and suck
while heat with buchner.
8. Repeat it 3 times with boiling water 125 mL.
9. It solution collect becone one after added 25 mL H2SO4 dilute.
10. Vaporate until 1/3 initial volume.
11. Extract with separating funnel with 15 mL chloroform 5 times.
12. Chloroform is vaporated and recris if there is crystal.
13. Test melting point to know the purity.
F. Observation Result
No. Observation Result
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Meassured sample (tea)
Filled sample to filtering paper
Added ethanol to soxhlet
Set soxlet and filled
Noted circulation
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
Taken extract
Mixed with MgO suspension and
150 mL water
Vapored it
Mixtured with water 250 mL
Filtered it buchner and 2 times 125
mL water
Vapor it until 1/3 volume
Filtered with buchner
50 g tea
3 times circulation
Sample in soxlet and tea colour
isn’t concentration
12 minutes
12 minutes
12 minutes
12 minutes
10 minutes
10 minutes
10 minutes
10 minutes
8 minutes
8 minutes
Brownish black solution
Green brown solution
Until formed powder
Black solution
Black solution
Brown solution
Brown solution
13.
14.
15.
16.
17.
Filled to separating funnel + 15 ml
chloroform + shaked (5 minutes)
Taken transparant solution and
keep it calm
The solution is heated
Balanced dust if caffeine
Determine dust caffeine melting
point
Separate 3 layers :
- Brown Solution
- Brown Transparant
- Transparant solution
Transparent solution
Dust of caffeine (yellow)
0,1596 g yellow dust
196-202°C
G. Discussion
In this experiment, used sample is tea, where tea is covered with filtering
paper and then into soxlet. Caffeine extraction from tea did with continuous
extraction by heating process with soxlet. The basic principal of soxlet is
extraction of compound in solid phase (tea) with liquid solvent (ethanol). In the
extraction process, used ethanol as the solvent because ethanol’s properties are
equal with caffeine, they are polar and low boiling point. In the extraction process,
some boiling stone is added into rounded flask in order to prevented explossion
occured in the rounded flask. In this stage, soxlet was set and the ethanol were
vaporated until three times circulation, the tea also covered with filtering paper
and then ethanol were heated. When the athanol condensed and passed through
condensor, the tea became liquid and collected until the ethanol back down to to
rounded flask. Heating process did until 10 times circulation. The first till the 4th
circulation were 12 minutes, the 5th till the 8th circulation were 10 minutes, and
the 9th till the 10th circulation were 8 minutes.
Caffeine is an alkaloid derived from coffee bean, tea leaves, and cacao
leaves. This extraction use tea because tea containing 4-5% caffeine more than
coffee. Caffeine is an alkaloid which contains alkali nitrogen with 194,19 grams
of molecular weight. The chemical formula of caffeine or 1, 3, 7-
trimethylxanthyne is C8H10N8O2 with chemical structure:
N
NN
N
O
O
CH 3
CH 3
CH 3
This extraction ended when the solution became thick or saturated. It
means the acquired extract is caffeine from tea (separation between caffeine from
tea powder). The result of this extraction was black-brown solution. This solution
added with suspension of MgO in water. suspension of MgO in water were to
help the solvent to push the caffeine from tea until it soluble into water and to got
the chemicals in tea, addition of MgO also purpose to kept structure of caffeine
when heating. Then the product solution vaporated till become powder. This
vaporation purposed to vaporing the solvent. After that both solution and powder
separated by filterizing. When filterizing occured, this solution added with hot
water because hot water could open the pores of caffeine so that there were more
caffeine extract and it could be extracted perfectly. The obtained filtrate were have
to be thicked again until 1/3 initial volume to vaporate water in filtrate so that
consentration of caffeine became thicker and another chemical that consist in
could be passed away. But before thicked, the filtrate added dilute sulfuric acid
(H2SO4) to decrease solution pH so that the structure of caffeine would not
damaged. In high pH (alkali), the structure of caffeine is easily damaged so that
it’s important to added some acid. Then this solution strained again.
The filtrate from last strain were into separating funnel. After that added
15 mL chloroform (CHCl3) into it. The filtrate were into separating funnel should
be in room temperature because if it were too cold, the solution would be
precipated because high molecular weight and pressure. Addition of choloroform
did 5 times, and shaked every in addition to increase contact chance between
caffeine and chloroform. This shaking might not too strongly because could result
emulsion between chloroform and water. While it were shaked, tap of separating
funnel opened occasionally so that volatile chemical from extract could be
vaporated. Addition of chloroform were to bind caffeine from solution so that
caffeine separated from another chemical in solution. Caffeine binded to
chloroform because chloroform were nonpolaric compound that could binding
another nonpolaric compound like caffeine.
The shaked solution devided into 3 layer. The upper layer was brown
because containing residue. The middle layer was light brown. It was caffeine
which still mixed with residue. The bottom layer was transparent. Smaller density
would be on upper layer. Caffeine solution filtered with buchner strainer so that
caffeine separated from another chemical. This solution added chloroform once
more so that remaining caffeine could be separated perfectly.
Separated caffeine heated to vaporating chloroform in solution. Result of
this vaporation were 0,1596 grams of yellow powder. This powder were purity
tested and acquired 196-202°C melting point. It was different with theory because
caffeine’s melting point was 227-202°C in theory. It was occured because the tea
were mixed with another chemical and also caffeine were not soluble perfectly.
The reaction of this experiment is :
NH
NH
N
H
N
H
+ 2C 2H 5OH
N
NN
H
N
CH3
O
O
CH3
(1, 3-dimethylxanthyne)
N
NN
H
N
CH3
O
O
CH 3
+ MgO + H 2O + 2CHCl 3
N
NN
N
O
O
CH 3
CH3
CH3
+ O 2 + 3Cl 2 + Mg2+
(1, 3, 7- trimethylxanthyne)
H. Closing
1. Conclusion
a. Caffeine is extracted from tea because of continuous extraction
process through heating
2. Suggestion
a. Apperantices should be carefull when adding chloroform.
b. Laborant must prepare our apparatus and chemical.
c. Assistant should be diligent to teach us about the procedure.
BIBLIOGRAPHY
Anshori. 2005. Organic Chemistry. Bandung: Padjadjaran University.
Bruice, P.Y.. 2003. Organic Chemistry 4th
edition. London: Longman Valey.
Caballero, M.J.. 2001. Extraction of Caffeine From Tea Leaves. USA: Dragon
Alley.
Carey, F.A.. 2001. Organic Chemistry 4th
edition. Virginia: M.C. Graw Hill.
Olcina, dkk. 2006. Effect of Caffeine on Oxidative Stress During Maximum
Incremental Exercise. Spain: Journal of Sports Science and Medicine.
ANSWER OF QUESTION
1. Structure of caffeine is :
N
NN
N
O
O
CH 3
CH 3
CH 3
2. Ethanol used bacause it is polar compound and also caffeine could be bond
with polar compound, So, caffeine could be solvent in ethanol and ethanol is
volatile so it will be easy to evaporated.
3. The melting point of a compound, specially it can be used to determine the
purity of caffeine if the interval is 1°C because the characteristic of pure
compound has interval of melting point as much as 1°C.