Sciencemadness Discussion Board

Phosphoric Acid from CocaCola

Abromination - 22-7-2018 at 09:46

Just for fun, I am attempting to extract the phosphoric acid from a can of Coke. Here are the ingredients:
CARBONATED WATER, HIGH FRUCTOSE CORN SYRUP, CARAMEL COLOR, PHOSPHORIC ACID, NATURAL FLAVORS, CAFFEINE.

For every hundred mL of Coke, there 17 mg of H3PO4 meaning that there are about 60 mg in one one ounce can (ew ounces).

The most obvious thing to do would to precipitate a phosphate salt out of a can of vacuum decarbonated Coke and turn it back into phosphoric acid with a bit of sulfuric acid.

Im planning on adding sodium carbonate to the coke to neutralize the phosphoric acid and then adding something to drop the phosphate out of solution. What would I use?

I will use this to add copper phosphate to my copper collection.

If you guys have a better way to do it I would love to hear>

Sulaiman - 22-7-2018 at 10:05

As copper phosphate is insoluble I would try just putting copper (or its oxide) directly into the coke.

Abromination - 22-7-2018 at 11:03

Quote: Originally posted by Sulaiman  
As copper phosphate is insoluble I would try just putting copper (or its oxide) directly into the coke.


I certainly could do that, but that takes all of the fun out of it. I would like to have the phosphoric acid as well, but I probably will just precipitate the copper phosphate out of the Coke.

DraconicAcid - 22-7-2018 at 12:02

Copper won't react with phosphoric acid directly, and the copper oxide would probably get coated with the phosphate and not fully react. Add a soluble copper salt such as copper(II) acetate. You may need to adjust the pH up to increase the concentration of phosphate ion.

Abromination - 22-7-2018 at 13:04

Quote: Originally posted by DraconicAcid  
Copper won't react with phosphoric acid directly, and the copper oxide would probably get coated with the phosphate and not fully react. Add a soluble copper salt such as copper(II) acetate. You may need to adjust the pH up to increase the concentration of phosphate ion.


Well I wouldn't add copper or copper oxide, I would add copper carbonate or add NaOH to form trisodium phosphate and then react that wuth CuSO4. Also ignore the copper phosphate part, I'm not as interested in that as actually extracting the phosphoric acid.

DraconicAcid - 22-7-2018 at 13:25

You don't want or need a high concentration of phosphate to precipitate the copper salt. If it's too basic, you'll also get copper(II) hydroxide precipitating.

Ubya - 22-7-2018 at 15:01

Quote: Originally posted by j_sum2  
Coca Cola is dangerous. According to some people it is almost as dangerous as gasoline. The effects of drinking are the same. You will notice various mushrooms growing on your whole digestive path, from mouth and nose to rectum. Some believe it is because phosphoric acid is eating and burning our meat, some consider sugar is guilty here, some consider some other ingredients.

I've been drinking cola for last 10 years non-stop. And I noticed my throat is becoming more and more red. Then some white spots, and dark red spots, and some holes like bullets pass through, then some meat started separating into threads, and so disgusting. According to normal and alternative doctors it is pharyngitis, tonsillitis, laryngitis, sore throat, various infections, symptom of allergy, and 1000 diagnosis.

But I am telling you it is because of coke. And other juices, drinks, teas, coffees, even water if excess or too cold. I feel pain in morning but it lasts only up to 1 hour after waking up. Probably because I breathe through mouth during sleep.

LOL, I learned in various books and sports that proper breathing or at least inhaling should be through nose, but my nose is clogged, not only with mucous or pus or watery substance, but with same mushroom like throat. When these mushrooms grow on ass people call them "hemmorhoids". But that is actually same shit, just different place. Just stop food, but you wont be able to stop it if you are not happy enough.

That's why God says in Qur'an something like: "happy people will go to heaven or succeed"
He also mentions one more people who will go to heaven and they are "first".
Only 1st people and happy people. What that means idk fully.
But makes some sense at least. You can not succeed through unhappiness or lack of hapiness.

Back to your topic: there are many ways to extract P from coke, but even that is better than drinking coke, or except same as my throat. :(


you could harvest those mushrooms and sell them to make a stew

Abromination - 22-7-2018 at 18:49

Im thinking that I can extract the phosphoric acid by adding calcium carbonate to the Coke and precipitating out calcium phosphate. Most phosphate salts are insoluble except for group one metals and some other stuff. With the filtered and washed calcium phosphate, I could react it with sulfuric acid and get phosphoric acid and calcium sulfate which wouldnt dissolve under the heat of the reaction. I could heat it as well to precipitate out any excess calcium sulfate and there I have a dilute aqueous solution of phosphoric acid.

Ubya - 23-7-2018 at 01:57

Quote: Originally posted by Abromination  
Im thinking that I can extract the phosphoric acid by adding calcium carbonate to the Coke and precipitating out calcium phosphate. Most phosphate salts are insoluble except for group one metals and some other stuff. With the filtered and washed calcium phosphate, I could react it with sulfuric acid and get phosphoric acid and calcium sulfate which wouldnt dissolve under the heat of the reaction. I could heat it as well to precipitate out any excess calcium sulfate and there I have a dilute aqueous solution of phosphoric acid.


100ml of Coke have 17mg of phosphoric acid
dicalcium phosphate has a solubility of 20mg/100ml in water
even calculating the mass of dicalcium phospate formed from the 17mg of acid i can speculate by eye that not much would precipitate if any

Abromination - 23-7-2018 at 14:03

Quote: Originally posted by Ubya  
Quote: Originally posted by Abromination  
Im thinking that I can extract the phosphoric acid by adding calcium carbonate to the Coke and precipitating out calcium phosphate. Most phosphate salts are insoluble except for group one metals and some other stuff. With the filtered and washed calcium phosphate, I could react it with sulfuric acid and get phosphoric acid and calcium sulfate which wouldnt dissolve under the heat of the reaction. I could heat it as well to precipitate out any excess calcium sulfate and there I have a dilute aqueous solution of phosphoric acid.


100ml of Coke have 17mg of phosphoric acid
dicalcium phosphate has a solubility of 20mg/100ml in water
even calculating the mass of dicalcium phospate formed from the 17mg of acid i can speculate by eye that not much would precipitate if any


Thats a fair point. I will probably be working with more than one can of Coke and can boil them down to increase the concentration of the H3PO4 and then add calcium carbonate to precipitate just enough dicalcium phosphate to react it with sulfuric acid. I will get q lowe yeild but it would still be something.

Texium - 23-7-2018 at 14:31

Your best bet would be to use larger bottles of cola rather than cans as they are cheaper by volume and more efficient. Even so, your maximum yield from a 3 liter bottle would only be 0.51 grams. If you were hoping to use this phosphoric acid for anything, you might want to reconsider. As I've said it before in another similar thread: due to the inpracticality and wastefulness of the endeavor, I don't think this extraction even has much academic value, much less any practical value. I'd recommend putting your energy towards something more useful and equally or more enlightening. There are many possibilities out there.

Abromination - 23-7-2018 at 14:46

Quote: Originally posted by Texium (zts16)  
Your best bet would be to use larger bottles of cola rather than cans as they are cheaper by volume and more efficient. Even so, your maximum yield from a 3 liter bottle would only be 0.51 grams. If you were hoping to use this phosphoric acid for anything, you might want to reconsider. As I've said it before in another similar thread: due to the inpracticality and wastefulness of the endeavor, I don't think this extraction even has much academic value, much less any practical value. I'd recommend putting your energy towards something more useful and equally or more enlightening. There are many possibilities out there.



You have a very valid point, but I simply like the ideo of extracting chemicals from every day goods. I am simply doing this for fun and do not expect to use it.
Anyways, I will use a bottle instead of a can.

happyfooddance - 23-7-2018 at 17:22

Make sure to boil all the CO2 out, otherwise you will have a lot of unnecessary carbonate mixed in with your phosphate. It would be better to use CaO or filtered limewater (best choice in my opinion) to neutralize.

Abromination - 23-7-2018 at 18:11

Quote: Originally posted by happyfooddance  
Make sure to boil all the CO2 out, otherwise you will have a lot of unnecessary carbonate mixed in with your phosphate. It would be better to use CaO or filtered limewater (best choice in my opinion) to neutralize.


I will put it in my vacuum chamber for a few minutes.
I also will use limewater instead of CaCO3.

[Edited on 24-7-2018 by Abromination]

symboom - 24-7-2018 at 00:08

What about calcium chloride you could also get some hydrochloric acid from the mix
H3PO4 + 2CaCl2 = 2CaPO4 + 4HCl
I think copper sulfate might work too leaving copper phosphate insouble and H2SO4

Sulaiman - 24-7-2018 at 00:52

Maybe before you start refining/extracting the phosphoric acid it would be good to do a titration first ?

examples found but not personally tried:
http://www.titrations.info/acid-base-titration-phosphoric-ac...
or probably more accurately using a pH probe
Attachment: CWV-35-COMP-phosphoric_acid.pdf (494kB)
This file has been downloaded 662 times

[Edited on 24-7-2018 by Sulaiman]

CobaltChloride - 24-7-2018 at 02:03

That would work if H3PO4 was the only acid in coke. Besides H3PO4 there's also citric acid in coca cola.

Abromination - 24-7-2018 at 15:55

Quote: Originally posted by CobaltChloride  
That would work if H3PO4 was the only acid in coke. Besides H3PO4 there's also citric acid in coca cola.


Actually, there is no citric acid in CocaCola, but there is carbonic acid from excess CO2 in solution.

clearly_not_atara - 25-7-2018 at 00:15

use fecl3

iron (iii) does not form a carbonate, and fepo4 is very insoluble.

symboom - 25-7-2018 at 17:47

So phosphoric acid by adding iron sulfate forming iron phosphate and sulfuric acid is that really possible
Sound like the sulfuric acid made from oxalic acid and magnesium sulfate weak acid forming a strong acid. Sulfuric acid??

Iron chloride and phosphoric acid would for hydrochloric acid which is. Volitile.

[Edited on 26-7-2018 by symboom]

[Edited on 26-7-2018 by symboom]

Abromination - 27-7-2018 at 14:51

What would the solubility of copper phosphate be? I imagine that it would be almost entirely insoluble, as phosphate salts (particularly with transition metals) are insoluble except for a few exceptions like alkali metal salts.

Also, could I use magnesium hydroxide instead of calcium hydroxide to precipitate out magnesium phosphate? I don't see a reason I couldn't but have learned the hard way that exceptions exist.

Abromination - 15-11-2018 at 22:26

I would just like to add that this failed completely, the iron phosphate that precipitated was too fine to be caught by any filter I had.

[Edited on 16-11-18 by Abromination]

[Edited on 16-11-18 by Abromination]

Tsjerk - 16-11-2018 at 08:05

Did you try precipitation with calcium?

GrayGhost- - 16-11-2018 at 08:24

Grosso modo is 0,02% of acid, you lost you time and effort in so few yield.

If I wrong someone say me please.