Extraction Labs

Purpose:

Technical: From a technical standpoint this lab should reinforce lab procedure we learned in the past, this includes separatory funnel technique, distiliations, and lab safety/proper use of glassware.
Educational: From an educational standpoint the purpose of this lab is to teach us the different methods of, extracting essential oils from different natural sources, however one of the labs was rather than a extracting a essential oil it was just an extraction so from more of a overview of the experiments it's educational goals was to understand how certain elements from a source can be extracted.

Hypothesis:

Cinnamaldehyde: I hypothesize we will produce a silver mirror when doing the tollens test, when reading through the lab sheet it is clear it should not be that hard to confirm you have gathered all material, because of that I believe it should be easy to have a successful experiment.
Caffeine: Upon reading the procedure for this lab, I knew that this lab would be hard to properly accomplish all the goals to perfection, I knew I would struggle getting perfect yield, so I hypothesize that my amount of caffeine will be less when compared to my peers.
Mint Oil: Not having a lab sheet for this lab makes me think we will have problems we didn't account for when completing this lab. When talking it through with my classmates it shouldn't be that hard of a lab but we have no idea what quantity of oil we will extract. Considering there is not that much essential oils in the mint leaves I hypothesize we will have a small yield.

Materials:

Cinnamon Lab:

Cinnamon sticks
About 5 large reaction vials
Petri dish
Spatula
Immersion heater
Ethyl ether
Multiple pipettes
Anhydrous magnesium sulfate
10% silver nitrate
10% sodium hydroxide
6 M ammonium hydroxide

Mint Lab:

Cut mint stems and leaves (about 8 grams or a handful)
Scissors
Florence flask
Support stand and ring
Condenser
Thermometer
Clamps
2 hoses
Multiple stoppers
Stacks of books or paper
Ring stand

Multiple or All Labs:

400 mL beaker
Weighing dish
Scale
Tongs
Distilled water
250 mL beaker(s)
Tap water
Test tube or reaction vial
Parafilm
Fume hood
Separatory funnel
5 mL graduated cylinders

Caffeine Lab:

Coffee grounds or 4-5 Tea bags
Sodium carbonate
Water-ice mixture
Ethyl alcohol
Ethyl acetate
Sodium sulfate
Funnel
Filter paper

Procedure

Cinnamaldehyde Extraction

Procedure

Set up the heater: Attach an immersion heater to the side of a 450 mL beaker and fill the beaker with water until the top of the heating coil is submerged. Plug in the heater to begin boiling the water.
Prepare cinnamon sticks: Smell the cinnamon sticks, then break them into smaller pieces with your hands. Weigh out approximately 2 grams using a tared weighing dish.
Add water and cinnamon to vial: Measure 5 mL of tap water using a graduated cylinder and pour it into a large reaction vial. Add the cinnamon pieces to the vial and seal it tightly with a Teflon-coated cap.
Heat the vial: Once the water is boiling, carefully place the reaction vial into the beaker of water, ensuring it is fully submerged. Let it heat for 25 minutes.
Cool the mixture: After heating, use tongs to remove the vial from the beaker. Set it aside to cool for a few minutes on a paper towel.
Transfer the solution: Once cooled, carefully transfer the liquid from the reaction vial into another clean reaction vial, leaving the cinnamon solids behind.

Isolation of Cinnamaldehyde

Add ethyl ether: Under a fume hood, measure 2-3 mL of diethyl ether using a graduated cylinder and add it to the vial containing the aqueous solution of cinnamaldehyde. Cap the vial and invert it about 30 times, releasing pressure periodically by loosening the cap slightly.
Separate the layers: Allow the vial to sit for 5 minutes until the layers separate clearly. Pipette out the top organic layer (which contains the ethyl ether and cinnamaldehyde) into a new, clean vial.
Dry the solution: Add anhydrous magnesium sulfate to the vial until the solution stops clumping, indicating it is dry. Transfer the organic layer to a Petri dish using a pipette.
Evaporate the ether: Let the ethyl ether evaporate under a fume hood for 10-15 minutes, leaving behind small droplets of cinnamaldehyde.

Analysis of Cinnamaldehyde

Weigh the Petri dish: Weigh the Petri dish before and after evaporation to calculate the mass of the cinnamaldehyde.
Smell test: Smell the Petri dish to note any distinct aromas from the cinnamaldehyde.
Tollens test: Perform the Tollens test for aldehyde confirmation. Add 1 mL of 10% silver nitrate to a graduated cylinder, and slowly add 6 M ammonium hydroxide until the silver dissolves. Add 1-2 drops of cinnamaldehyde to the mixture, seal the vial, and shake for one minute. A positive result will form a silver mirror after about 5 minutes.

Caffeine Extraction

Procedure

Prepare water solution: Measure 100 mL of distilled water with a graduated cylinder and pour it into a 250 mL beaker.
Add sodium carbonate: Weigh out 4.01 g of sodium carbonate using a tared weighing dish and mix it into the beaker with a stirring rod until fully dissolved.
Add tea bags or coffee grounds: Weigh about 15 g of coffee grounds (or tea bags) and add them to the beaker. Stir well to combine.
Heat the solution: Place the beaker on a hot plate and heat to just below boiling, stirring occasionally to prevent foaming. Allow the solution to heat for around 15 minutes.
Cool the mixture: Remove the beaker from heat and let it cool to room temperature.
Filter the solution: Set up a vacuum filtration system using filter paper, a funnel, and a side-arm Erlenmeyer flask. Filter the solution to separate the solid grounds from the liquid.
Perform the extraction: Under a fume hood, add 25 mL of ethyl acetate to the filtered solution. Transfer the solution to a separatory funnel and invert it, releasing the pressure periodically. Allow the layers to separate, then drain the lower aqueous layer and keep the upper ethyl acetate layer.
Repeat the extraction: Add another 25 mL of ethyl acetate to the separatory funnel and repeat the extraction. Combine the ethyl acetate layers in a beaker.
Evaporate the solvent: Heat the ethyl acetate solution in a 100 mL beaker on a hot plate under a fume hood until the ethyl acetate evaporates, leaving behind crude caffeine.

Purification of Caffeine

Part A: Crystallization

Prepare boiling stones: Using forceps, transfer the boiling stones from the beaker into a clean 50 mL beaker.
Heat ethyl alcohol: Pour 20 mL of ethyl alcohol into the 50 mL beaker and heat it on a hot plate under the fume hood. Do not let the alcohol boil—heat it just below the boiling point.
Dissolve the caffeine: Pour the hot ethyl alcohol into the 100 mL beaker containing crude caffeine. Swirl gently with a stirring rod until the caffeine dissolves.
Induce crystallization: Place the 100 mL beaker in a 250 mL beaker filled with cold water and ice. Allow the solution to cool, and within 5 minutes, crystals should begin forming. Let the solution sit for an additional 10-15 minutes to allow complete crystallization.
Filter the crystals: Weigh a small piece of quantitative filter paper, then filter the caffeine crystals through it, using a funnel. Allow the filter paper to dry and weigh it again with the crystals.

Part B: Sublimation

Prepare the sublimation setup: Weigh an empty 50 mL beaker, then fill it with an ice water mixture. Transfer the crude caffeine from the filter paper into a 100 mL beaker.
Set up the beakers: Place the 50 mL beaker inside the 100 mL beaker, creating a sealed sublimation system.
Heat the beakers: Place the beakers on a hot plate and heat gently. As the temperature rises, the caffeine will sublime onto the bottom of the smaller beaker.
Cool and collect crystals: After sublimation, remove the assembly using tongs and allow it to cool. Carefully remove the ice from the inner beaker, dry the beaker, and weigh it with the sublimed caffeine crystals.
Final step: Scrape off the sublimed caffeine crystals for final weighing and dispose of waste materials properly.

Mint Oil Extraction

Procedure

Weigh the mint leaves: Using a tared weighing dish, measure around 8-10 grams of fresh mint leaves and stems. Cut them into small pieces as needed.
Add water to flask: Place the mint pieces into a 500 mL Florence flask, then measure and pour 150 mL of tap water using a graduated cylinder.
Set up distillation apparatus: Secure the flask on a ring stand with a clamp. Attach a condenser to the top using a rubber adapter, and clamp the condenser securely to the stand as well.
Insert thermometer and hoses: Insert a thermometer through the top of the condenser, aligning it with the point where vapor will enter the condenser. Connect hoses to the condenser for cold water flow.
Start heating: Turn on the hot plate to bring the water and mint leaves to a boil, allowing the vapors to pass through the condenser.
Distill the mint oil: As the water boils, the mint oil will begin to distill. Continue heating until a sufficient amount of distillate is collected in the separatory funnel.
Separate the layers: Once the distillation is complete, pour the distillate into a separatory funnel. Allow the layers to separate, then drain the lower aqueous layer into one beaker and the mint oil layer into another.
Smell test: Smell both the aqueous layer (which will have an earthy scent) and the mint oil (which will have a strong minty aroma).
Dispose materials: Properly dispose of any waste and clean up the apparatus.

Data Analysis Collection

Petri Dish Smell for Cinnamaldehyde: The smell was present which surprised me considering that all of my droplets had dissolved and there was only a little bit of a solid, but that solid smelled strongly of cinnamon.

Tollens Test: The test had not worked, because when I did the evaporation and only the Cinnamaldehyde drops should have remained I only had a solid left on the periti dish. So I tried to use distilled water to dissolve it so I could use it for the tollens test.

Caffeine Crystallization: My crystallization barley worked, the first crystallization worked but very few amount of crystals, however the sublimation didn't work at all.

Mint Oil Extraction: This lab I could tell the difference between mint oil and mint water. I could tell the scents at the end of my experiment. My mint water smelled like I was in a swamp, its a hard thing to describe but it did smell vaguely reminiscent of mint. However, the mint oil smelled like true mint that I have smelled before in candy and teas.

Conclusion:

Through the extraction lab, it was possible for me to grasp several sorts of compound isolation and methodologies that are mainly attributed to the right separation of substances. Some processes were not easy, I got to understand why all those things need to be performed in that manner and with precision. This laboratory was particularly useful after the ester synthesis lab because it could help me interlink the concepts of synthesis and extraction in a better way to enhance my ability of separation of various scents and compounds whether they were esters, aldehydes, or any other kind of compound. The presence of the condenser in both labs has proved the concept that similar apparatus can serve in different ways for different experiments. I made errors and procedures were not working right, but we were able to learn from it and do our experiments to satisfaction. The designing of the equipment for mint extraction had to be redone after the first design probably would have blown up if we had done it, this showed that not all equipment is suited to particular methods. On the whole, the results of the experiments were varied. The mint extraction went well by being able to differentiate mint oil and the swampy water, whereas other labs, like the Tollens test with the caffeine sublimation, did not go as smooth. The cinnamon extraction lacked enough ethyl ether, which directly affected our outcome for the Tollens test. An accident in the caffeine sublimation stopped me from finishing correctly. Aside from all the challenges, the use of an immersion heater and the skill of filtering, and separation, and distillation have been learned and enforced. Since all substances we extracted have different properties, different methods were used. Hence, the choice of method becomes very important. This series of labs brought about not only the development of my lab skills but also my mental ones. That is, the ability to interrelate knowledge obtained in old labs to these extraction procedures.

Reflection:

The lab taught the importance of accuracy and also attention to detail in synthesizing esters. After working with ethyl acetate and octyl acetate, it had shown that minor changes in procedure make a difference in the results, like the unexpected nail polish remover and citrus cleaning product like smell. The steps of isolation and purification that the esters went through really put into perspective how important each step is in attempting to get the highest yield and purity. This also allowed me to be fully involved within the experiment and to really reinforce such concepts as reflux and separation. It was a great practical experience that really made me understand esterification and also aspects of problem-solving required in the laboratory.

Lab Sheets:

Cinnamonaldehyde Extration.pdf

CamScanner 10-21-2024 21.30.pdf

Page updated

Report abuse