Sciencemadness Discussion Board

sodium laureth sulfate

Magpie - 5-3-2018 at 21:42

Sodium laureth sulfate [SLES, (sodium lauryl ether sulfate)], after water, is the major ingredient in Colgate-Palmolive's "SoftSoap" liquid hand soap. This soap is incredibly strong, ie, I can wash my face with 1 drop + water. I would love to make some of this in my lab. SLES has this formula: CH3(CH2)11(OCH2CH2)nOSO3Na. Wiki says that n is the mean but is typically = 3.

Anyone know how to do this?

[Edited on 6-3-2018 by Magpie]

TGSpecialist1 - 6-3-2018 at 02:05

Industrially it is made by reacting lauryl alcohol with 3 mole equivalent ethylene oxide (highly toxic and flammable gas) then with chlorosulfonic acid and neutralized with sodium hydroxide/carbonate.

aga - 6-3-2018 at 02:56

Certainly looks like a complicated synthesis.

"SLES is prepared by ethoxylation of dodecyl alcohol. The resulting ethoxylate is converted to a half ester of sulfuric acid, which is neutralized by conversion to the sodium salt."

https://www.revolvy.com/main/index.php?s=Sodium%20lauryl%20e...

... doedecanol via the "Ziegler Process"
... ethylene from ethanol & sulphuric acid
... ethylene oxide from 2-chloroethanol & KOH
... 2-chloroethanol from ethyene & hypochlorous acid
... hypochlorous acid from ...

Sure is hard to find detailled info out there.

Tsjerk - 6-3-2018 at 03:41

Maybe Sodium Dodecyl Sulfate (SDS) is easier to find.

markx - 6-3-2018 at 05:12

"Silipon RN 31 HDH" is an air entraining agent for drymix mortars and is basically pure SLS. We use it to soften cementitious mortars and alter their rheology in a delicate way by adding trace amounts (30g/ton e.g)

SLS in dry form is an awful thing to handle....the irritating effect on eyes and throat is catastrophic. It feels like breathing in chili pepper dust even in the slightest trace amounts.

TGSpecialist1 - 6-3-2018 at 08:14

You could extract fatty alcohols from beewax, and already ethoxylated fatty alcohols are available for sale.

Mothman - 6-3-2018 at 13:25

I got about 5 lbs of sodium dodecyl sulfate on amazon, I think that you could buy it here too:
https://www.bulkapothecary.com/sodium-lauryl-sulfoacetate-sl...

If you haven't run out of lye like myself, you could perhaps convert SDS to lauryl alcohol and go through the process to produce SLS, but SDS is also an effective soap in it's own right, plus you can use SDS for decellularizing tissues.

Also the reports of SDS being a pain to handle while dry are very true. I bought a huge (5lb) bag of the stuff on amazon and when it arrived, I popped it open expecting some tame, dry soap. My haste in opening the bag resulted in a large amount of the exceptionally fine powder being ejected into the air, which I of course breathed in a large quantity of when I inhaled sharply in surprise at the sight of a large white cloud. I was coughing for a good hour after that, my eyes felt like they had just had jalapenos jammed into them, and my nose burned like diethyl ether on an unattended hotplate. Subsequent interactions with this compound have been conducted with more knowledge of this compound's properties, and without such idiocy in the process of opening the bag, so things aren't nearly as bad as that first encounter, but still my throat and eyes burn during and after opening my bag of SDS. The moral of the story is that even non-dropped soap can ruin your day if you aren't careful.

If you decide to take the SDS-->lauryl alcohol-->SLS route, be cautious, it's a mean compound in dry form, though solutions are only as bad as soapy water.

NEMO-Chemistry - 6-3-2018 at 16:36

Some people are really allergic to it, i avoid SLS or any its derivatives. Very cheap to buy from soap suppliers.

Oh and before I forget....dont try and smell it, it really burns your nose. :D

RogueRose - 6-3-2018 at 19:12

Quote: Originally posted by Mothman  
I got about 5 lbs of sodium dodecyl sulfate on amazon, I think that you could buy it here too:
https://www.bulkapothecary.com/sodium-lauryl-sulfoacetate-sl...

If you haven't run out of lye like myself, you could perhaps convert SDS to lauryl alcohol and go through the process to produce SLS, but SDS is also an effective soap in it's own right, plus you can use SDS for decellularizing tissues.

Also the reports of SDS being a pain to handle while dry are very true. I bought a huge (5lb) bag of the stuff on amazon and when it arrived, I popped it open expecting some tame, dry soap. My haste in opening the bag resulted in a large amount of the exceptionally fine powder being ejected into the air, which I of course breathed in a large quantity of when I inhaled sharply in surprise at the sight of a large white cloud. I was coughing for a good hour after that, my eyes felt like they had just had jalapenos jammed into them, and my nose burned like diethyl ether on an unattended hotplate. Subsequent interactions with this compound have been conducted with more knowledge of this compound's properties, and without such idiocy in the process of opening the bag, so things aren't nearly as bad as that first encounter, but still my throat and eyes burn during and after opening my bag of SDS. The moral of the story is that even non-dropped soap can ruin your day if you aren't careful.

If you decide to take the SDS-->lauryl alcohol-->SLS route, be cautious, it's a mean compound in dry form, though solutions are only as bad as soapy water.


No wonder all the soaps with SDS or SLS burn the shit out of your eyes! I had used home made soap with simple NaOH/KOH and it was never anywhere near as painful when getting in eyes. I just though I was being more careful. I'd rate "natural soap" a 1/10 vs some of the SDS/SLS based soaps as a 6-8/10 in how much they burn the eyes. Never really knew what was making the soap painful. Thanks for your story!

Tsjerk - 7-3-2018 at 02:06

I don't know SLS, but SDS is as detergent as a detergent can get. Good if you need a detergent, but needs some caution when used on the skin/eyes.

TGSpecialist1 - 7-3-2018 at 03:52

SLS and SDS are the same thing, maybe you meant SLES?

Dr.Bob - 7-3-2018 at 17:45

The polyethylene glycol portion can be bought premade in various lengths, n=1, 2, 3, 4, ... with various pieces on either side, one of my old coworkers worked for a company that made various ethylene ether pieces with linkers on each end. Many liquid detergents are simple polyethylene ethers with an alcohol or acid on one end, those have no strong acid or basic groups, so they are much less irritating, thus used in baby shampoo and woolite type cleaners. Once you put a sulfonic acid on the chain, it becomes a much stronger detergent, but also harsher. And if you take a fatty acid and then convert to the amine and make the quat salt from it, those are good disinfectants (Lysol), as well as anti-static agents like used in Bounce sheets or fabric softener. Just making old fashioned soap from fat and lye is a great chemistry experiment, as is making biodiesel from fat and MeOH/NaOMe. Every student should do those as a lab in school. If most people understood what protein, fat, and sugars were, it would be a great start for biochemistry, but many "well educated" people have no idea what is even iin their food. (Hint, food contains chemicals, even the stuff from Whole foods/paycheck...)

Tsjerk - 8-3-2018 at 02:19

Quote: Originally posted by TGSpecialist1  
SLS and SDS are the same thing, maybe you meant SLES?


That is what I said right? So I meant SDS (apparently the same as SLS), not SLES.
Quote: Originally posted by Tsjerk  
I don't know SLS, but SDS is...