EDB workshop
The Hong Kong University of Science and Technology
Department of Chemistry
MICROSCALE ORGANIC EXPERIMENT
Catalytic Hydrogenation of Methyl Oleate
Dr TSUI, W. M.
Basic Safety & Waste Disposal Procedures
Personal Safety
1. Safety glasses must be worn at all times in the labs. Contact lenses should not be worn
in the lab because chemicals and particulates can get caught behind them, causing severe
eye damage.
2. Lab gown must be worn in the labs where an unexpected chemical spill may expose you
to the risk of injury. The following clothing is not permitted in the labs unless covered
by protective clothing:
 Open-toed shoes, sandals or other uncovered footwear; clothes that expose above the
ankles;
 Eating, chewing gum, and drinking in the lab.
 Untied long hair, dangling jewelry, loose clothing, and anything else that may get
caught in equipment, or dipped in chemicals.
3. Never work alone or unsupervised in the labs. Work only during the scheduled
laboratory periods and perform only authorized experiments.
 Wash your hands, arms, and then face, with soap and water as soon as possible after
leaving the lab.
 If you are uncertain about any safety aspect of an experiment, please ask your TA.
Lab Safety
 Make sure you know the exact locations of the safety features of the lab; e.g.,
eyewash fountains, safety showers, chemical spill kits, fire extinguishers, fire alarms,
fire blankets.
 Whenever possible, do not deal with incidents on your own. Your TA, the lab
instructor and the technician are all trained to respond to the sort of incidents that
may occur in this lab; e.g. chemical spills, cuts, burns, fires, medical emergencies, etc.
 Keep your work area clean and organized to reduce the possibility of accidents.
Know what you are doing and don't be careless.
 Avoid unnecessary exposure to chemicals. Never pipette by mouth. Never taste or
inhale a chemical on purpose. Wear gloves when directly working with hazardous
chemicals. Use hoods when appropriate.
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


Take appropriate precautions. Keep flammables away from hot plates and open
flames. Wear gloves when using toxic, carcinogenic, or other hazardous chemicals.
Take care with corrosive acids and bases. Always pour concentrated acid slowly into
water (never water into acid). Read the Safety Issues section at the beginning of each
experiment.
Be informed. Material Safety Data Sheets (MSDS) summarize known hazards
associated with every chemical are available from the lab.
Chemicals & equipment may not be removed from the lab without permission from
the Lab Instructor.
Disposal of Chemical Waste
It is very important to properly dispose the chemical waste you generate. Follow these
guidelines and dispose of your waste properly, to avoid adding to the contamination of our
environment.
• Generate as little waste as possible. It is expensive to have hazardous waste removed and
disposed. Don't prepare more of a chemical than you expect to use.
• Never return unused portions of chemicals to the reagent bottle. At the end of your
experiment, unused reagent must be disposed of as waste, so don't pour out more than
you need.
• Don't discard chemicals down the sink or in the wastebasket, unless you are explicitly
told that it's okay to do so. Most of your chemicals will pose a threat to the environment
if disposed improperly.
• Place chemical waste only in the appropriate container. Often, more than one waste
container is provided to separate certain chemicals for safety or easier disposal. Pay
attention to the Waste Disposal information for each experiment in this lab manual, and
use the waste containers indicated. If you cannot find a waste bottle labeled with your
particular chemical, ask your TA where to dispose it.
• Fill in the appropriate waste inventory sheet. There is separate inventory sheet for each
waste container. Use it to record the chemical(s), concentrations and volume you dispose.
• Do not over-fill a waste container. Tell the technician the bottle is getting full and they
will replace it.
• Use the clearly marked GLASS containers to dispose of broken glass and Pasteur
pipettes. Do not place broken glass in the sink or wastebasket, to avoid serious injury to
an unsuspecting person.
• Use the clearly marked WASTE SOLIDS wide-mouth bottles to dispose of waste solids.
Waste solids include solid chemicals, filter paper, and weighing paper.
• If you realize that you disposed of a chemical in the wrong container, use the waste
inventory list provided by the waste container to let us know.
• If you have waste whose identity you can’t recall, you can often test your waste, e.g.,
with litmus paper, to deduce its identity. Do not add unidentified waste to the waste
bottles. You will force us to categorize the entire waste container as “unknown” which
becomes extremely expensive to identify and dispose of.
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DEPARTMENT OF CHEMISTRY
Hazard Identification Sheet
Name: ________________________
Experiment Title:
MICROSCALE ORGANIC EXPERIMENT – Catalytic Hydrogenation of Methyl Oleate
Date of Experiment: ________________________________
 I have read and understand the instructions stated in ‘Basic Safety & Waste Disposal
Procedures’ concerning the proper use of the chemicals.
 I shall work in compliance with the aforementioned instructions made by the ‘Basic
Safety & Waste Disposal Procedures’.
SECTION I:
General Hazards Identified for the Experiment

I shall handle hazardous inorganic chemicals during the experiment. I shall follow
the instructions specified in ‘Basic Safety & Waste Disposal Procedures’.

I shall handle organic solvents and chemicals during the experiment. I shall follow
the instructions specified in ‘Basic Safety & Waste Disposal Procedures’.

I shall dispose hazardous waste chemicals during the experiment. I shall follow the
instructions specified in ‘Basic Safety & Waste Disposal Procedures’.
[please tick  where it is appropriate]
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SECTION II: Specific Chemical Hazards
For classification of hazards, please check the Material Safety Data Sheet (MSDS)
established
by
The
Sigma-Aldrich
Company
at:
http://www.sigmaaldrich.com/chemistry.html
Hazard Flammable Corrosive
Toxic
Irritant
Harmful
Oxidizing Explosive
Others
Chemical
Celite
Hydrochloric acid
(Concentrated)
Hydrogen
Methanol
Methyl oleate
Palladium (10%) on
carbon
Zinc
[please tick  where it is appropriate]
* Others: Carcinogenic, Allergic, Lachrymatory, Narcotic, Teratogenic, Reproductive
hazard, Central nervous system depression, Dangerous to the environment, Asphyxiant,
Poison
SECTION III: Declaration
This form to be completed by participant:
I am well aware of the hazard(s) of the experiment(s) to be carried out in the Chemistry
Laboratory.
Name:
Signature:
Date:
(in block letters)
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EDB workshop
The Hong Kong University of Science and Technology
Department of Chemistry
MICROSCALE ORGANIC EXPERIMENT
Catalytic Hydrogenation of Methyl Oleate
Dr TSUI, W. M.
Chemical hazard notes
Concentrated hydrochloric acid is corrosive and toxic; handle with care.
Disposal of wastes
Organic reagents and solvent must be disposed to appropriate waste solvent bottle.
Introduction
Methyl oleate was hydrogenated to methyl stearate in the presence of the catalyst
10% palladium on carbon (Scheme 1) and the hydrogen source is generated from the
reaction of zinc metal with hydrochloric acid. The hydrogen uptake in this reaction can
be followed as water rises in the hydrogen reservoir i.e. the graduated cylinder (see the
figure on the last page).
O
H3C
O
Methyl oleate (Methyl cis-9-octadecenoate)
O
H2
H3C
10% Pd, C
O
Methyl stearate (Methyl octadecanoate)
Scheme 1
The volume of a millimole of hydrogen at standard temperature and pressure is
22.4 mL. This can react with one millimole of a compound which contains a double bond.
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In this experiment, you only have to hydrogenate 0.4 mmole of methyl oleate and it will
use up about 9 mL of hydrogen. Thus, a 10 mL graduated cylinder should be enough to
hold the gas.
Procedure
1.
Into a 5-mL round-bottomed flask (flask A) add 60 mg of 10% palladium on carbon,
a small magnetic stirring bar and 1.5 mL of methanol. Cap the flask with a rubber
septum and wrap it tightly with parafilm.
2.
Sharp the ending of a 12 inches piece of polyethylene tubing by a scissor and insert it
into the rubber septum.
3.
Fill a 250-mL beaker and a 10-mL graduated cylinder to near the rim with water.
4.
Clamp the graduated cylinder in an inverted position over the beaker of water.
5.
Into another 5-mL round-bottomed flask (flask
B) add 1 g of granulated zinc and close it with a
septum containing another 12 inches piece of
polyethylene tubing.
6.
Inject 10 drops of 6M hydrochloric acid to flask
 Polyethylene tubing
B with a syringe to generate hydrogen and wait
for 1 minute. (see the figure on the right)
7.
Insert the other end of the polyethylene tubing
into flask A. Add another 10 drops of 6M HCl
into flask B to generate more hydrogen, wait for
 rubber septum
another 1 minute. During this time, remember to
turn on the stirrer briefly to saturate the methanol
 zinc inside 5-mL
round bottomed flask
and the catalyst with hydrogen.
8.
Thread the outlet of the tubing (from flask A) into the graduated cylinder and inject
more 6M hydrochloric acid (0.5 mL should be more than enough) slowly onto zinc
and fill the reservoir with hydrogen.
9.
Disconnect the hydrogen generator from flask A after 8 – 9 mL of hydrogen is
collected in the inverted measuring cylinder (see the following figure).
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10. Turn on the stirrer and note any changes in the water level in the reservoir. If it comes
to the same level as the water on the outside, it means that there is a leak in your
system! Seal your flask A with parafilm if necessary.
11. Once the pressure in the system has stabilized, turn the stirrer off.
12. Weight 80 mg of methyl oleate. Dissolve it into 0.5 mL of methanol and inject the
methyl oleate solution to the reaction flask (flask A).
13. Immediately record the volume of hydrogen in the reservoir. Turn on the stirrer and
note the volume of hydrogen in the reservoir as a function of time. Be sure the end of
the polyethylene tubing is always above the water level in the reservoir.
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14. When the water level is no longer change with time, your reaction is finished. Record
again the volume of hydrogen in the reservoir. The difference between initial and
final volume of hydrogen in the reservoir is the approximate volume of hydrogen
consumed in the reaction.
15. Remove the polyethylene tubing from the reservoir and the reaction flask.
16. Push a piece of cotton-wool firmly into a Pasteur pipette.
17. Fill the pipette with about 0.5 inch of Celite.
18. With a second pipette transfer about 1 mL of methanol to wash the pad of Celite.
19. With the same pipetter, transfer the reaction mixture to the filter pipette and allow the
solution to pass through the pad of Celite in order to remove the catalyst to give a
clear colorless solution into a reaction tube.
20. Rinse the reaction flask, stirring bar and transfer pipette with a few milliliters of
methanol, filter this rinsing also.
21. If the filtrate appears grey, repeat the filtration process.
22. Reduce the volume of the methanol solution in the reaction tube to about 1.5 mL by
evaporating the solution with a stream of dry air in a warm water bath.
23. Cool the tube in an ice-water bath for 20 minutes.
24. At the same time, cool about 5 mL of methanol in the same ice-water bath.
25. Collect the solid by suction filtration while the mixture is cold. (This can be also
done by removing the liquid by pipet filtration)
26. Wash the solid with small amount of ice-cold methanol.
27. Suction dry the white solid and transfer the dry solid into a vial.
28. Add 0.5 mL of water dropwise to the filtrate to isolate a second crop of product.
29. Suction filter the solid formed to obtain the second crop of product.
30. Record the weight of your product.
31. Determine melting point of the product.
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Data
Initial reading in the reservoir = __________________
Final reading in the reservoir = ___________________
Volume of hydrogen consumed = __________________
Weight of product (first crop) = ____________
Weight of product (second crop) = ____________
Total weight of product = ____________
Percentage yield of product: (Please show all the calculation steps)
Melting point of product = _________________
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Questions
1. What happen in Flask B? Include in your answer the appropriate chemical equation.
2. What is the purpose to wait for 1 minute in step 6 and 7 after HCl is added?
3. What is the catalyst used in this reaction? Is it a homogeneous or heterogeneous
catalyst? Why?
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