Does anyone know how to cleave glycerol from triglercides, leaving behind free fatty acids?

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Captante

Lifer
Oct 20, 2003
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uclaLabrat

Diamond Member
Aug 2, 2007
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Thank you uclaLabrat! Might you walk me through the process a little more?

So you have the triglycerides with the glycerol at the end. The acid cleaves the glycerol. But HCL is, I believe, H and Cl. Does it replace the glycerol with a Cl? Or does it leave it in its free form?

And by extracting it, I assume you mean separating the FFA from the glycerol and the Cl and whatever is also in the oil I started with? What does ethyl acetate do when you add it to the mix? Where do the FFAs and what not go from there?

Thanks!!!
If you take triglycerides and saponify them with sodium hydroxide, once done add hydrochloric acid to bring the pH down to about 2. At pH 2 the fatty acid will be re-protonated and neutral (not a salt). Add ethyl acetate and it will form a separate layer from the aqueous solution. Shake it up and the glycerol and salt will partition into the water, the free acid will partition into the ethyl acetate.

Separate the two phases and boil off the ethyl acetate and you'll have (kinda) pure fatty acid. Well...triglycerides are a mix of acids so you'll get whatever was in the mix. And some glycerol will tag along for the ride.
 

WelshBloke

Lifer
Jan 12, 2005
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If you take triglycerides and saponify them with sodium hydroxide, once done add hydrochloric acid to bring the pH down to about 2. At pH 2 the fatty acid will be re-protonated and neutral (not a salt). Add ethyl acetate and it will form a separate layer from the aqueous solution. Shake it up and the glycerol and salt will partition into the water, the free acid will partition into the ethyl acetate.

Separate the two phases and boil off the ethyl acetate and you'll have (kinda) pure fatty acid. Well...triglycerides are a mix of acids so you'll get whatever was in the mix. And some glycerol will tag along for the ride.
I would pay money to watch Salty fuck this up on camera!
 

SaltyNuts

Platinum Member
May 1, 2001
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If you take triglycerides and saponify them with sodium hydroxide, once done add hydrochloric acid to bring the pH down to about 2. At pH 2 the fatty acid will be re-protonated and neutral (not a salt). Add ethyl acetate and it will form a separate layer from the aqueous solution. Shake it up and the glycerol and salt will partition into the water, the free acid will partition into the ethyl acetate.

Separate the two phases and boil off the ethyl acetate and you'll have (kinda) pure fatty acid. Well...triglycerides are a mix of acids so you'll get whatever was in the mix. And some glycerol will tag along for the ride.


THANK YOU UCLALABRAT!!!!!!

OK, I've got a ton of questions, but first I want to order everything I'm going to need.

The main fatty acids I want to isolate in free form are:

gamma-linolenic acid
alpha-linolenic acid
linolenic acid


So, for gamma-linolenic acid, it looks like borage oil has a bunch, and evening primrose oil, which has less but is cheaper. So I should order some of those correct?

For alpha-linolenic acid and linolenic acid, it looks like they are high in almost all vegetable oils, so I'll just use some like vegetable or canola oil from the old lady's pantry.

Sodium hydroxide, I'll order it from ebay.

hydrochloric acid - did you say that is the same as muriatic acid that they sell at Home Depot? Any idea where I would find it there (what section)? I would guess the pool section. Looks like one can also order it on ebay cheap enough it looks like.

ethyl acetate - I see this on ebay, not cheap, but I can buy it no problem - but are there places to get it local cheaper?

Let me know what else if anything I need to get uclalabrat! I would guess for boiling and what not I can just use kitchen pots and the stove? And when I'm mixing the stuff up with the HCA, can I just use a plastic Home Depot bucket? Or will that melt, and I need something different? If different, what should I get?

Let me know anything else you think I'm going to need to I can order it and we can get this party started!!!!
 
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SaltyNuts

Platinum Member
May 1, 2001
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Also uclalabrat, I have some shitty ph meater around that I use sometimes to measure hydroponic solutions, will that work, or do I need a more sturdy one that can handle ph's down to 2? Or do I even need a PH meter because I'll just add X amount of HCA to Y amount of other stuff and it will assuredly take the PH low enough?

Thanks!!!
 

Torn Mind

Lifer
Nov 25, 2012
11,897
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hydrochloric acid - did you say that is the same as muriatic acid that they sell at Home Depot? Any idea where I would find it there (what section)? I would guess the pool section. Looks like one can also order it on ebay cheap enough it looks like.
Yes, it is at Home Depot and muriatic acid is the same as hydrochloric acid. One bottle is about $10 and categorized under the concrete cleaning section and the HDX branded 2 pack for $13 is categorized in the concrete cleaner section.


The Klean Strip might be diluted more though. They keep the actual percentage a trade secret but it is 10-30% while the HDX has the percentages on the bottle.
 

SaltyNuts

Platinum Member
May 1, 2001
2,398
275
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Yes, it is at Home Depot and muriatic acid is the same as hydrochloric acid. One bottle is about $10 and categorized under the concrete cleaning section and the HDX branded 2 pack for $13 is categorized in the concrete cleaner section.


The Klean Strip might be diluted more though. They keep the actual percentage a trade secret but it is 10-30% while the HDX has the percentages on the bottle.


Thanks Torn dude! I'll get the HDX one, seems like a bargain. It is a little weaker than the strongest I'm seeing on ebay and what not, but stronger than many others. I suspect that will work just fine!
 

SaltyNuts

Platinum Member
May 1, 2001
2,398
275
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Awwwwww, hell yea! Guess what this is? Potassium hydroxide flakes that I actually bought for something else awhile back. UCLAlabrat, I take it these will work just as good as Sodium hydroxide? Thanks!!!



20211002_190037.jpg
 

Torn Mind

Lifer
Nov 25, 2012
11,897
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Thanks Torn dude! I'll get the HDX one, seems like a bargain. It is a little weaker than the strongest I'm seeing on ebay and what not, but stronger than many others. I suspect that will work just fine!
It's not practical for HCl to have a concentration of 40% or more.
As an aside, you can make table salt from NaOH and HCl. But the reaction is helluva exothermic and you have to measure right, using moles and whatnot. Otherwise, excess will remain and need further neutralization.

These two are complete opposites on the acidity spectrum but both are dangerous on contact without neutralizing chemicals. Baking soda will safely neutralize HCl and vinegar for NaOH.

Hydrochloric acid will react with most metals. Any steel, even stainless is definitely no bueno; I used it to dissolve rust and bust up tough toilet stains. You need to use glass if you are going to boil HCl, and do that outside. The fumes will come out and they linger in the atmosphere. The metals in your kitchen will not appreciate that, nor your eyes.
 
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Red Squirrel

No Lifer
May 24, 2003
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www.anyf.ca
If you're really serious about this stuff do wear proper PPE and do in well ventilated area... this could be recipe for serious disaster lol. some of the gases you can end up creating can be super toxic. Wear safety goggles, respirator etc (covid mask won't do crap, you need something proper)
 
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uclaLabrat

Diamond Member
Aug 2, 2007
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You are to by absolutely no means EVER TO USE A FLAME HEATING SOURCE WHEN DOING THIS. Heating mantles are best, specifically variable voltage, or a hot plate with some sort of bath.

Realistically for ethyl acetate you can just let I evaporate instilled of distilling it.
 

SaltyNuts

Platinum Member
May 1, 2001
2,398
275
126


Thanks Torn Mind! But I think they've just done what we are going to do here no? And I don't think Sunflower Oil fatty acids really have that much of the fatty acids I am looking for. No, let's make history here, together. Now.
 

SaltyNuts

Platinum Member
May 1, 2001
2,398
275
126
If you're really serious about this stuff do wear proper PPE and do in well ventilated area... this could be recipe for serious disaster lol. some of the gases you can end up creating can be super toxic. Wear safety goggles, respirator etc (covid mask won't do crap, you need something proper)


Thank you Red Squrrel. Is all that really necessary if I'm just going to make a few hundred ML of the stuff? I'm talking very small quantities for the trial runs until we perfect the process. I just can't imagine that if I make 500 ml of the stuff that even if the gas it puts out is pure lung corrosive crap it would do much damage, given the small quantities haha.
 

SaltyNuts

Platinum Member
May 1, 2001
2,398
275
126
You are to by absolutely no means EVER TO USE A FLAME HEATING SOURCE WHEN DOING THIS. Heating mantles are best, specifically variable voltage, or a hot plate with some sort of bath.

Realistically for ethyl acetate you can just let I evaporate instilled of distilling it.


Thanks LabRat! Can you recommend one in particular, off amazon or ebay? Looking for one that will do the job at least amount of $$$ possible. But its got to do the job!!!



Also, reposting from above in case you did not see it, I've updated it with what I've gathered so far:

THANK YOU UCLALABRAT!!!!!!

OK, I've got a ton of questions, but first I want to order everything I'm going to need.

The main fatty acids I want to isolate in free form are:

gamma-linolenic acid
alpha-linolenic acid
linolenic acid


So, for gamma-linolenic acid, it looks like borage oil has a bunch, and evening primrose oil, which has less but is cheaper. So I should order some of those correct? I WILL PROBABLY JUST BET EVENING PRIMROSE OIL FOR TRIAL RUN SINCE A BIT CHEAPER AND SUPPOSEDLY MAKES A NICE SOAP LOL.

For alpha-linolenic acid and linolenic acid, it looks like they are high in almost all vegetable oils, so I'll just use some like vegetable or canola oil from the old lady's pantry.

Sodium hydroxide, I'll order it from ebay. I ACTUALLY HAVE POTASSIUM HYDROXIDE ALREADY, ANY PROBLEM JUST USING THAT TO MAKE THE SOAP? I DO NOT THINK SO.

hydrochloric acid - did you say that is the same as muriatic acid that they sell at Home Depot? Any idea where I would find it there (what section)? I would guess the pool section. Looks like one can also order it on ebay cheap enough it looks like. YES GETTING MURIATIC ACID FROM HOME DEPOT PER TORN MIND'S LINK.

ethyl acetate - I see this on ebay, not cheap, but I can buy it no problem - but are there places to get it local cheaper? THOUGHTS?

Let me know what else if anything I need to get uclalabrat! I would guess for boiling and what not I can just use kitchen pots and the stove? And when I'm mixing the stuff up with the HCA, can I just use a plastic Home Depot bucket? Or will that melt, and I need something different? If different, what should I get? NEED HEATING THING-A-MA-JIGGIE.

Let me know anything else you think I'm going to need to I can order it and we can get this party started!!!!
 

Torn Mind

Lifer
Nov 25, 2012
11,897
2,716
136
Potassium will work. It will be a liquid soap.
Thank you Red Squrrel. Is all that really necessary if I'm just going to make a few hundred ML of the stuff? I'm talking very small quantities for the trial runs until we perfect the process. I just can't imagine that if I make 500 ml of the stuff that even if the gas it puts out is pure lung corrosive crap it would do much damage, given the small quantities haha.
Eye protection is the primary thing with the fumes. Goggles should definitely be worn. Clothes should be something you don't care about or a Tyvek coverall.
They are capable of attacking skin but won't cause major harm unless you get soaked and also are incapacitated. They are not hard to deal with if you have the appropriate neutralizers(vinegar for NaOH, baking soda for HCl) on hand with you and apply them promptly. You don't want to pour vinegar or baking soda in your eyes though because they too will hurt. So definitely protect the eyes from any splatter. Make sure to have an organized workspace.