The only thing constant in life is Change - Heràclitus of Ephesus. Chemistry is a wonderful language: the language of Matter and its Interactions. Also, chemistry is pervasive: wherever we turn we can find signs of its presence. Doing chemistry is having your eyes open at the same time on the heart of the stars and inside every living cell, in the depths of the rocks and at the center of every single atom *. I’m an undergraduate student, studying Pharmacy at UniPd, Italy. This channel will explore chemistry from the simplest projects to the most interesting theory beyond them.
* (G. Bandoli, A. Dolmella, G. Natile, Chimica di base - II edizione, 2003, EdiSes S.r.l)
very interesting practical this video really helps me because I'm having the practical today and i get it before getting to the Laboratory thanks so much for the update
I use a Clevenger apparatus for essential oil extractions. Less losses of final product than when using a separatory funnel considering the small quantities.
Hii! thank you for the video. I wanted to ask, what ratio of water to plant material (orange peels) did you use? Just an approximate guess is fine. Thank you!
We can't say it. It's not pure. We can assume it contains an appreciable amount of limonene since we know the typical high percentage contained in the orange. (The high evaporation rate confirms its presence in a high percentage, though) Other molecules are also present in smaller quantities. For a quantitative value of purity, we should carry out a quantitative analysis or an NMR.
Just a small question: Why do you use sodium bicarbonate and not sodium carbonate (soda)? You would need lees of it and it would generate only half of the CO2 compared to sodium bicarbonate. That would make the addition easier.
@@francesco.cinzano OK I see. I just wondered because where I live sodium carbonate is available as a cleaning agent just at the supermarket and it's really cheap.
It can be or 1) if you cooled the solution quietly it can became oversatured and so require some perturbation (or another crystal) to precipitate the salt; 2) the solution you are cooling is not saturated.
Quick question! Does the rest of the baking soda still need to be in the beaker while cooling down or do we take the remaining unmelted baking soda to cool without it? Also, when the unmelted baking soda is removed, and then you let it cool, does it just form the sodium acetate powder/gel by itself in the fridge?
The amount of baking soda should be stoichiometrly correct. Because it's easier to remove unreacted acetic acid (evaporation) than to remove undissolved baking soda (filtration) you can put a bit less than it should be.
When you added baking soda to acetic acid, sodium acetate is already in the baker, but dissolved. You need to evaporate all the water in order to obtain the sodium acetate powder. If you want to (like in the video) observe the crystallization process, you cool down the saturated solution and then see the crystal precipitating.
It depends on your equipment such as your heater and your refrigerator. The more it cools down, the more oversaturated the solution became. If you let it too long it can start precipitation spontaneusly.
Isn't this considered hydrodistillation instead of steam distillation? From what I've looked into, steam distillation separates plant matter from the boiling water instead of the water and the plant matter all being together in a mixture. Does this separation of water and plant matter necessarily need to be the case in order for it to be considered steam distillation or does your method still count as steam distillation?
Yup, you need a lot of caution since it is hygroscopic and caustic, and new stoichiometry calculations (Na2CO3 is 2:1 and NaOH is 1:1 with acetic acid)
Since crystallization is a purification process by itself, no other steps are required to purify the product it crystallizes. If you want to purify further you can always do one more cycle, losing in yield.
@@CinzLab I´ve always wondered what sort of impurities would give that golden-orange color in concentrated solutions of usually colorless acetates like sodium acetate.
thanks Guys, it's a really cool video. I'm interested in extracting for use in the kitchen. Ddo you know if the pesticide residues in the lime skin with be transferred to the limonene during the distilattion process?
Other videos I have watched usually add a solvent to the hydrosol/oil mixture and use heat in order to separate, I don't understand why they bother. I find confusing because the two should separate naturally with the oil being non polar as in your video. Is it a yield or purity thing?
The extraction with a solvent is the standard when we have to extract a liquid from another liquid. The extraction of Limonene is also possible with a solvent, like hexane or a non-polar one, and it definitely would maximize the yield. The extraction of Limonene is also possible without a solvent just because limonene oil has a lower density compared with water. So it naturally floats on the surface. If you performed an extraction with different oil, like the eugenol, it still won't mix with water, but its density is instead very similar, and the oil will form a suspension of very small oil droplets in water. The purity of Limonene is directly reliant on the natural composition of the oil, which can slightly change from fruit to fruit. Limonene is however the major component (>80%) of the oil.
@@CinzLab Thank you so much for taking the time to reply to my question. I found it very confusing and you've explained it in a way that was easy to understand
Limonene is totally apolar, being aliphatic, therefore a good solvent must necessarily preserve this characteristic. Furthermore, it must have an appreciable difference in terms of density with respect to water in order to float or sink and make it possible to extract only the apolar phase with the separator funnel. Finally, it must be volatile, in order to be easily removed. Hexane, DCM, acetone... should work.
"D-limonene is listed in the Code of Federal Regulations as generally recognized as safe (GRAS) for a flavoring agent and can be found in common food items such as fruit juices, soft drinks, baked goods, ice cream, and pudding. D-limonene is considered to have fairly low toxicity." pubmed.ncbi.nlm.nih.gov/18072821/ pubmed.ncbi.nlm.nih.gov/23573938/ Caution in chemistry is mandatory. Many harmless substances in small doses become dangerous in large quantities.
For the quantification of chemical compounds mainly instrumental methodologies based on physical principles are used. In this video, as you could see, a quantification was not carried out, but an estimate was based on the composition of the essential oil extracted. To learn more about the methods of quantifying limonene, I refer you to this article: www.perkinelmer.com/PDFs/downloads/APP_Limonene_In_Citrus_Rinds_By_GCMS.pdf
@@CinzLab Thank you very much for this. You are a blessing ♥️. We will be having a reporting about this and I am having a hard time coping up and how to explain it :(
My videos are set to be enjoyable and exhaustive as much as possible about every experiment. A slow and peaceful video is essential to allow people to understand the concepts and also to appreciate the clips. This’s the compromise I found. The reason why I didn't put the yield in the video is the following (I already answered to this question few comments below): as you can see from the video, a water drop joined along with the oil in the test tube and prevented me to quantify exactly the oil extracted. Removing that drop wouldn’t be worth it. I got about 3 ml of oil: the usual yield is claimed online to be 1%, depending on the variable quantity contained in every single fruit.
@@bodo9387 You're welcome. Yes, from 112g of peels. The yield could be maximise extracting the oil from the distillate with a solvent like DCM (di-chloro-methane) but I do not have a fumehood or an equipped workspace to handle it so I preferred to take advantage of its density property and separate it just with the funnel.
Provide a short description of your setup. Did you use something that may have contaminated the electrolyte, for example exposed copper wire partially immerged during charging/discharging?
@@CinzLab i use 6 M KOH and 0.2 M zinc acetate as the electrolyte. zinc foil as the negative electrode, carbon paper as the positive electrode, and the battery like this website www.advancedsciencenews.com/new-air-electrodes-zinc-air-batteries/ There is no other metal in the battery except zinc.
@wayne In the electrolyte should be present mostly zincate ions and some zinc oxide and zinc hydroxide as byproduct. All of them should be colorless however. What about the yellow color? Does it appear in the discharging process or after the discharging/charging sequence? At the moment I'm thinking about an acetate byproduct, as far as you have an organic component in a strongly caustic solution, that could someway decompose it in a sort of long term side-reaction. Do you observe the same phenomenon also without using zinc acetate?
CinzLab During charging and discharging, yellow will be slowly produced, and the color will become deeper and deeper. However, zinc acetate is mainly used as a substance needed to provide a reversible reaction, so it must be added. What are the possible byproducts of zinc acetate?
About 3mL of Limonene. The presence of that drop of water prevented me from carrying out an evaluation with the balance. I didn't remove it just because I thought it isn't worth it, as far as the yield is very low. Usually the yield is about 1% (from NileRed) but it can widely change depending on the single orange. Some organges contain a lot of essential oil, some less. Same for lemons.
Definitely not as efficient as zinc bromide battery showed by the guy. As he says, to make a battery there are a lot of things to consider. Just the fact that in my project I used Na2CO3 instead NaOH as electrolyte killed the efficiency of the cell (and I needed to make x3 to light a LED). Air battery are sensitive to air purity and oxygen concentration and because they need air, aren't so easy to handle (you can't have a isolated case). The zinc bromide seems a great and documentated-useful alternative to this kind of battery.
Biodiesels are long chain fatty acid esters, obtained by vegetable oils (triglycerides) reacting with methyl/ethyl alcohols through a process called trans-esterification. Essential oils, like limonene, have different structure and properties and their flammability doesn't lead to an efficient and useful role in biodiesel.
