NaOH strange result

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penelopejane

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i was making a tester soap batch.
I was dividing the mix into four.
One cup had 35g water, 12 g FO, 1/2 tsp salt, 1/4 tsp citric acid. This was the only part with CA so I added 1.5 g NaOH to neutralise the CA.
Immediately it formed 2 mm soft balls in the bottom of the cup.
I couldn’t squash them or reincorporate them. There were no hard lye pearls left.
Does anyone have any idea what the NaOH reacted with?
Has this happened to anyone else?
I threw it away and mixed the NaOH with plain water first then added the other ingredients and it worked fine.
Will the soft balls reform later within the soap?
 
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I have had weird precipitates when adding either CA or EDTA directly to lye solution. I know I've taken pictures but can't find them now. Didn't affect the soap as far as I could detect. I don't use CA any more, but I now add the EDTA to the oils and blend it in well before adding the lye water. No surprises since I started doing it that way. I still add my simple sugar solution to the lye water, and though it turns orange, I've never seen any precipitate.
 
I have had weird precipitates when adding either CA or EDTA directly to lye solution.

Thank you CaraBou. I thought of taking a photo but I didn't want to ruin my good mobile phone with battery fingers (I am a messy soaper). : (
It certainly was weird. I might be able to replicate it.

This was during a test to see if I can replace CA with Sodium gluconate.
I am starting to think that it is a necessity!
 
penelopejane

Can't be sure, but if it happens again (or if you want to waste time and materials) and try and replicate the experiment it might be indicative.
I would take out the "soft balls" and see how they behave:

1) if you leave them out, do they dry into something crystalline or hard as a salt? Or do they absorb humidity and melt down into a thick puddle?
this might be an indication of what it is, a citrate will absorb water, NaEDTA would not (on a short term, or depending on how humid the air is).
sodium chloride is also quite insoluble when there are many other sodium salts around that are far more soluble that it is, for example NaOH, or citrates or EDTAtes.

2) put them in plain distilled water, see if they dissolve back.
this might exclude some weird thing going on with your FO. But not if the FO had some water-soluble component, you might have salted-it-out when adding the NaOH and thereby increasing the ionic strength of your mix.

3) try to dissolve them in isopropyl alcohol, or high-proof vodka. Salts usually do not dissolve well. If they do, it's most probably something from your FO.

Was it a new FO you were testing? Was it phthalate free? Phthalates react with lye just like glycerides do (same ester functional group), as do parabens.
Some fruity FO contain esters (butyl acetate for bananas for example), and some "balsamic" FO might contain benzoates, as fragrance compound or as solvents (replacing phthalates).

Curious to know more about it...
Cheers,
L.
 
penelopejane

Can't be sure, but if it happens again (or if you want to waste time and materials) and try and replicate the experiment it might be indicative.
I would take out the "soft balls" and see how they behave:

This just goes to show why I did straight physics at school and no chemistry.
I tried to replicate the experiment without the FO to no avail.
Then I thought it might be the FO.
Casting frugality to the winds I poured some FO into the dissolved mix (NaOH prills, CA, Salt and water) - nothing happened.
Then I put NaOH prills into the mixed FO, water, CA and salt and the balls appeared.

Interestingly if I mix NaOH only and water THEN add the FO nothing happens (same as the mix with additives). The FO sort of forms globules of oil on the top but no balls. It is only after I add NaOH prills to water and FO or to dissolved NaOH and FO that the globules form.

The FO is mint mojito by Eroma Australia (they make their own so not a US FO)
Description: A citrusy and sweet blend reminiscent of the summertime cocktail. Additional notes of white rum, sugar cane and spearmint make this fragrance a potent combination.

It is phthlate free and Nitro Musk free
The flash point is 64*

Got to say the FO does smell nice so I'd like to keep it. Method is going to be important!
IMG_0047.jpg IMG_0048.jpg
 
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Could the non-water-soluble FO be coating particles of the NaOH as they fall through the FO layer and preventing the particles from dissolving in the water? Something vaguely along the lines of flour lumps in gravy?

I wouldn't typically add FO to the water-based liquids, so maybe add it to the fats instead?
 
PenelopeJane -- I did a double take when I read this. The image that came to my mind was "Edward Scissorhands" with AAA batteries rather than scissors. Thanks for lightening up my day! :)

I am devastated to admit (much to my DH's horror) that I am not a clean soaper like the wonderful lady on Soaping 101. I would like to think that I am getting better but this was a particularly tricky multi split batch. Complex is my middle name. :computerbath:
 
Could the non-water-soluble FO be coating particles of the NaOH as they fall through the FO layer and preventing the particles from dissolving in the water? Something vaguely along the lines of flour lumps in gravy?

I wouldn't typically add FO to the water-based liquids, so maybe add it to the fats instead?

I have never added NaOH after the fact before either.
I usually add NaOH to part of the water in the mix at the beginning.
This time I was testing additives and I had 4 different parts of the batch. One had CA so needed extra NaOH to neutralise the CA which I added to that particular water mix.

I think the flour lumps in gravy is a perfect description of what happened. Not just as they were falling though the FO layer but they picked out the FO as I stirred. The NaOH appeared to dissolve and then form the lumps. The lumps are soft and oily.

Yes I think adding the FO to the oils is a good idea.
At least it isn't the CA.
 
Glad you figured it out. Somehow I missed that you had added FO to the watery mix. My experiences had no FO involved, and it didn't look like your pics. Great pics, by the way.

In addition to adding EDTA to the oils instead of the lye mix, I also switched to buying lye from a soap supplier, rather than using hardware/drain cleaner grade lye like I always had before. I was having enough problems, and could visibly see enough impurities, I figured it couldn't hurt.

I perked right up seeing your post, but I guess they were unrelated. If I ever have problems again, I'll be sure to post! Glad you figured out your problems.
 

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