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Glycerine and KOH turning brown???

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Mildreds.naturals

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I'm using the Glycerine method to make my liquid soap.

I purchased a huge amount of it in March 2013 (about 8 gallons). I also bought a lot of KOH from Essential Depot.

I made liquid soap with this a little less than 2 years ago. I made a lot of soap. I heat up the Glycerine to about 230 degrees and add the KOH slowly. It never turned brown but the last two batches of soap, it turned to an espresso cream color. The soap turned out fine but this chemical reaction is changing the color of my soap to be very dark it seems. I was mixing it with the exact same utensils I used last time (glass container and plastic heat resistant spoon).

Has anyone had this happen?

From what I've seen, Glycerine has a shelf life of 3 times what times has passed since I've had it and I can't imagine the KOH would go bad?
 

liquidsoaplady

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I don't if this the case........

But it is important to store your supplies in a cool dark place.

KOH can and does absorb moisture form the atmosphere, rendering it to a liquid state eventually, it is very important to pour out what is needed and seal it immediately.

As far as glycerin, it depends on it's purity, pure vegetable vs synthetic ingredients.

I would venture to say the older the ingredients the more likely they will not perform as well over time.
 
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Susie

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I think you are overheating your glycerin. Try mixing the KOH with half the liquid amount in water first, then once dissolved, add to the other half of the liquid amount in glycerin, then the oils and see what you get. As mentioned above, the KOH can also go bad by absorbing too much moisture. Weigh those bottles to be sure they are still in the correct weight range before using. I weigh mine after each use and write it on the bottle, then weigh again before next use to be sure it has not absorbed moisture.

DeeAnna(I think) suggested storing lyes in a half of a tub of clay kitty litter to let the litter absorb the moisture before it can get to your KOH or NaOH. Works well for me. No more increasing weights on the lyes. It will also allow me to order more at the time, therefore saving shipping costs.

ETA-Not DeeAnna, sorry Lee! Here's the thread, it is post #20.

http://www.soapmakingforum.com/showthread.php?t=53198&highlight=litter&page=2
 
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LBussy

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I made liquid soap with this a little less than 2 years ago. I made a lot of soap. I heat up the Glycerine to about 230 degrees and add the KOH slowly. It never turned brown but the last two batches of soap, it turned to an espresso cream color. The soap turned out fine but this chemical reaction is changing the color of my soap to be very dark it seems. I was mixing it with the exact same utensils I used last time (glass container and plastic heat resistant spoon).
Do you mean the soap turned brown, or the glycerin mix?

Glycerin boils at 554°F so I don't think you are over heating that. It will definitely get hot enough, quick enough, that I think a plastic spoon would not be a good idea. Even if it does not melt it could begin to leach chemicals, especially after some time being used. Out of all you have described that's the only part which raises any flags for me. Is there any chance you can switch to stainless steel for this?

When I dissolve KOH now I do it a little different (I thought I was so cool for having thought of it, but then I see IrishLass and a few others did it before me!). I add the KOH to the cool glycerin, stir it up and break up lumps. THEN I heat it up slowly. There will be boiling but my hypothesis is that it is the moisture adsorbed into the KOH, and I'm pretty sure glycerin is hygroscopic as well. If that's the case it will eventually stop and the temp will spike - until then it should stay under 220-230 or so.
 

Saponista

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When I tried heating my glycerine in the crock pot and adding the KOH slowly it turned brown as it took so long to melt. I also think that you are possibly overheating the glycerine as I did it in a pan on the stove this time and it stayed clear as it got hotter but only for a short time.
 

Mildreds.naturals

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Do you mean the soap turned brown, or the glycerin mix?

Glycerin boils at 554°F so I don't think you are over heating that. It will definitely get hot enough, quick enough, that I think a plastic spoon would not be a good idea. Even if it does not melt it could begin to leach chemicals, especially after some time being used. Out of all you have described that's the only part which raises any flags for me. Is there any chance you can switch to stainless steel for this?

When I dissolve KOH now I do it a little different (I thought I was so cool for having thought of it, but then I see IrishLass and a few others did it before me!). I add the KOH to the cool glycerin, stir it up and break up lumps. THEN I heat it up slowly. There will be boiling but my hypothesis is that it is the moisture adsorbed into the KOH, and I'm pretty sure glycerin is hygroscopic as well. If that's the case it will eventually stop and the temp will spike - until then it should stay under 220-230 or so.
I am microwaving my glycerine to about 230 or so.
The KOH came from Essential depot and was in individual bottles, but the one I used was in a half empty bottle that is over 2 years old.
I'll try using one of the unopened bottles, but i weighed the bottle and all and it was 2.12 lbs so I think that means it's pretty on point. If the unopened bottle produces no brown color when mixed with my heated up glycerine, I'll know it may have had something to do with moisture absorption. The KOH has been stored in their original containers in a drawer, cool and dark. I must say, it made this beautiful amber color, kind of like the color of maple syrup, but I can't have inconsistencies with color.

I'll also try a metal spoon. I've never heard of adding the KOH to Cold glycerine, and I wouldn't want to do it with my crock pot indoors, I usually do it in a graduated beaker on the back patio.
 

Mildreds.naturals

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Alright I'm guessing this crap is bad. I grabbed the unopened KOH and it didn't turn brown like last time but did change with a tinge of brown. I'm going to pin the blame on the KOH and assume the Glycerine is fine. I mean it's glycerine.

I used this recipe from soapcalc:

Coco 92 degree 4.96 oz
palm kernel flakes from bulkapothecary.com 3.84
olive oil from costco 3.84
castor oil 1.60
hemp oil 1.76

Soapcalc says KOH 3.98 (i put 4oz)

2% superfat
checked 90% pure KOH also.

This sucks! I emailed Essential Depot. The KOH is 2 years old, but it was stored in the containers they came in and in a drawer that was cool and dark. If I stored it according to recommendations, shouldn't I be seeking replacement? I will make another batch tomorrow from another container and also after mixing it up in case whatever was near the top was crap. I will say that I tried adding some KOH to room temp glycerine and it did react and got very hot like usual.

Unrelated: I emailed Essential Depot when I received the 5 bottles of 2lb KOH. Reason was because they misslabled them. They said SODIUM hydroxide so when I asked them what they sent me and that I didn't know what I received well, they never answered me! So i just tested a batch and it worked fine.
 

LBussy

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I saw your post in the other thread. The adulteration of the KOH in the past seemed like moisture, I'd not heard of any strange colors. If it was NaOH it would not have done that either (but would have made some snotty soap). All very strange.

I'd be interested to hear how it turns out with a new batch of KOH - and if it were me I'd also be ready to try a different source of glycerin just to rule it out.
 

Mildreds.naturals

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I saw your post in the other thread. The adulteration of the KOH in the past seemed like moisture, I'd not heard of any strange colors. If it was NaOH it would not have done that either (but would have made some snotty soap). All very strange.

I'd be interested to hear how it turns out with a new batch of KOH - and if it were me I'd also be ready to try a different source of glycerin just to rule it out.
I agree.

I actually went and made another batch, this time, i dumped out some of the KOH from the container and used it from the middle of the unopened container. I made the same batch. success! I also noticed that the browning effect in the glycerine was very faint. I used the same spoon and beaker that i've always used in the past, also so I know it wasn't that. I know the KOH is 2 years old and the label has a best by jan 2015. Essential Depot rep said that if it's stored properly it should last longer than that. I'm guessing that some problems might arise if I keep using this stuff but i'll make some batches with the new KOH and my current glycerine before making any conclusions.
Thank you everyone for contributing.
 

LBussy

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Well it's not what I would have expected, but it is good info.

I wonder if it's carbonates? Potassium Carbonate is formed when Potassium Hydroxide is exposed to CO2 in air. A good test would be to procure some and add that to a batch to see if the color is similarly impacted. I would not know how to go about accounting for its alkalinity, but a simple 1:1 replacement with Lye in a sacrificial batch would let you know if that's it. A not as great but potentially interesting way to do it would be to intentionally introduce the impurity in a "classic" manner. This could be by exposure of the lye to carbonated water (this may well be a violent reaction), "carbonating" lye water, or using traditional wood ash leech to make a batch of liquid soap.

It "seems like" the issue is an adulteration/contamination due to exposure to the air - based on you using some from the middle of the container. The only two adulterants I can think of which could result from that are water and carbonate (CO2) .. neither of which sound right but you have results there which beg to differ. "Traditional" wood ash soap was not brown and we use water in the process anyway. Weird.
 

Mildreds.naturals

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So I got my new KOH delivered and made a couple batches. It most certainly was bad lye. The Glycerine is fine. My olive oil has an expiration date that has passed (costco), so I bought new oil to use. I don't suppose the olive oil could also be bad? it's not that much if I have to toss it.

KOH that is unopened is now in Plastic zip lock bags! Thanks for all your help
 

LBussy

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Only one way to tell ... New lye+old oil test batch. Or pitch it which I think I might choose after the frustration. :)
 
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