Soleseife soap

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"... ...Calculate minimum amount of water needed to dissolve lye = 13.4 * .77 = 10.3 oz ..."
Moving on, I am befuzzled about the number 0.77 in this calculation. Even the referenced solubility table doesn't support the use of that value. ???

Thank you DeeAnna, I should have showed my math better :)
100g of Water will dissolve ~130g of lye
130g lye / 1.3 = 100g water
1/1.3 =.77
130g lye * .77 = 100g water
 
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I see your point now that you've clarified. Thanks -- I wasn't following your train of thought very well!

You are basically creating a recipe based on "full water" (about 27-28% NaOH solution concentration) then you are splitting the water into two imaginary parts. You are using one part of the water to make a saturated NaOH solution at 104 deg F (40 C). You are using the other part to make a saturated salt solution.

I'd sure not want to make soap using a real-life 56% lye solution -- that would be far too temperamental for me. But it's clear this method of splitting up the water to calculate the salt for solseife is giving you good results. Hey, that's great!
 
"...But why, DeeAnna? I started the experiment by completely dissolving the salt. ...."

Yes, but you dissolved it in plain water. When you added the NaOH to the salt-water solution, you changed the rules of the game. Just because a chemical is dissolved in one set of conditions doesn't mean it will remain dissolved if you change the conditions.

For example, one way to make a "rock" candy is to heat plain water and white sugar to form a super-saturated solution. My brothers and I used to hang a cotton string down into the container of sugar solution and wait. The temperature change and time will cause the sugar to recrystallize back into solid form around the string.

You're doing much the same thing with the salt solution -- you're making a near-saturated solution of salt in water, then adding the NaOH. In this case, it's the added lye, not the change in temperature, that is causing the recrystallization/precipitation, but the general idea is pretty much the same.
 
"...Lye is unique that it can absorb more than it's own weight of water..."

Um, might want to re-think this statement. A solution that contains more solvent (water) than solute (NaOH) is extremely common.

If you're talking about hygroscopy (the ability of a solid material to absorb water from the atmosphere), NaOH is not unique. Zinc chloride, KOH, calcium chloride, as well as NaOH are all examples of deliquescent materials. And it doesn't really relate to the issues in this thread, anyways.
 
Interesting Google search "soleseife rezept" click here

Lavender Sole
250 g coconut oil
250 g olive oil
250 g Shea Butter
200g sunflower oil
50g castor
335 g of cold, distilled water
131 g NaOH at 9% over-enrichment
 
"...But why, DeeAnna? I started the experiment by completely dissolving the salt. ...."

Yes, but you dissolved it in plain water. When you added the NaOH to the salt-water solution, you changed the rules of the game. Just because a chemical is dissolved in one set of conditions doesn't mean it will remain dissolved if you change the conditions.

I understand that. But what makes you certain that in such case only salt can precipitate out of solution? Please help me to overcome the fear of undissolved lye.
 
Oh. I wasn't following your train of thought, Fata.

It is my opinion that the white precipitate is salt (NaCl), because salt is so much less soluble (26%) at room temperature than the sodium hydroxide (52%). But I do not have absolute confirmation -- that comes from testing the chemical content of the precipitate, and I haven't done that.

If you are concerned that NaOH is recrystallizing and you don't want that, you need to back off on the salt concentration to an amount that allows the NaOH-NaCl-water solution to remain clear, not milky. That way you can "have your cake and eat it" -- in other words, you can have your salt-brine soap and not be fearful.
 
Thanks for the nice thread. I wonder how much lye concentration % do you guys think best for making soleseife?

---
Moya.
 
The recipe:
100% coconut oil
20% superfat
26% salt
Coconut milk for water substitution.
 
I have done neither the experiments nor the calculations, but I have tried dissolving from both directions and I can say categorically that NaCl will not dissolve into a solution of NaOH. Not even a single teaspoon for a regular "non-soleseife" batch will dissolve in lye. I believe like DeeAnna that the cloudiness when you go the other way is NaCl precipitated from solution.

In fact, I think that precipitate is the point of making soleseife. We've all experienced - or at least read about here - problems with salt bars being too rough because the salt crystals were too big. That can be an especial problem if a mined salt like pink Himalayan because the crystals, no matter how small, are irregular and rough. So the idea with soleseife is to get a lot of salt in the bars without making them rough. Dissolving the salt in water first, then letting it precipitate out of solution when the NaOH is added makes tiny, fluffy salt crystals that are nice on skin.
 
I add any of the salt that precipitates out of my brine solution, which I master batch with hot distilled water, into my batter. I do need to mention I know it is salt not lye. When I mix my lye into my room temp salt brine clear with no problems. Like Brewer George mentions it is not scratchy. I melted down a chunk of Himalayan, it was a candle holder that I was tired of, just to prove I could not get anything higher than a 25% brine and 25% was it. As for salt bars I still prefer non-iodized table salt or a few brands of x fine pacific sea salt, but table salt makes the smoothest non-scratchy salt bars. For my soleseif soap I usually use a 31% lye concentration.
 
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I usually run the salt down at 20% and then add the NaOH. The lye then looks normal but the bars do need to be cut sooner than a "regular" recipe. The salt does harden the batch quicker.

I think what's going on here is that the Sodium hydroxide has a much higher affinity for water than salt or sugar or most other additives) so it must be added after the other additive are completely dissolved or the additive can only achieve a solution. Thus it will precipitate back out. If 26 or 27% salt is in the water the sodium hydroxide will strong arm the water molecules away from the salt (NaCl)
 
"...Sodium hydroxide has a much higher affinity for water than salt or sugar or most other additives)..."

I agree about NaOH being more soluble than NaCl (table salt) so you have to add the salt first to get the desired result.

The issue with adding table sugar into lye solution vs. into plain water is not related to solubilty. There is a chemical reaction between components of the sugar and NaOH. If this reaction occurs when the table sugar is still in large grains, the sugar granules clump together into a mass. If you get the sugar dissolved first, the reaction still happens, but on a molecular level.
 
:FacePalm: OMG. I never thought to not count the water used to dissolve lye before calculating the amount of salt I could use... Light.bulb.moment. I must also now correct a soapmaking friend that I gave bad advice too... oh sweet jesus. Maybe soleseife soaps should be a monthly challenge...? @The Efficacious Gentleman thanks for chiming in with the correct German pronunciation. I was going to as well. I've heard quite a few Americans murder this one (pronunciation and making of --> looking at myself), so once I discovered it was a German soap I had one of my German colleagues teach me the correct way to say it.
 

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