"Oil & Vinegar" sodium acetate in soap experiment

[CaraBou]

Thanks for the explanations. Clearly it was an oversight not to recognize your chemistry skills in addition to those related to math and overall documentation. I did okay (Bs) in college chem but it took a lot of work and didn't come very naturally. Glad there are people like you on the forum to make it a little easier for soaping!

I have heard a lot of people here talk about wanting to harden their soaps, but I am on the fence. Maybe if I sold or was opposed to animal fats, I would be more concerned. Could you provide insight to the benefits as you see them? Sorry for such a basic question; it seems so silly.

 

[topofmurrayhill]

I have heard a lot of people here talk about wanting to harden their soaps, but I am on the fence. Maybe if I sold or was opposed to animal fats, I would be more concerned. Could you provide insight to the benefits as you see them? Sorry for such a basic question; it seems so silly.

It's not silly. Like you, I never took much of an interest in adding a hardener. To me, the recipes in the crafting community are biased too far towards the soft side on the average. I blame Soapcalc and its BS about "conditioning oils." My soaps are hard and have the qualities I want, so my experimental bottle of sodium lactate was tried and then stashed away because I didn't feel I had a use for it.

Old soapmaking sources suggest that sodium lactate and sodium acetate are useful hardeners when soap needs to be made from soft oils. If you look up the SL demo in the Soaping 101 YouTube channel, you'll see an especially dramatic example: she makes soybean oil soap with and without SL. Like any self-respecting linoleic oil, soybean wants to turn into soft, translucent sticky gunk instead of soap, and that's what had to be pried out of the mold for the plain version. The SL version popped out of the mold looking clean, opaque and hard like a normal soap.

When I heard that sodium acetate worked like SL and realized I could make it from vinegar, I had to try it. That's just me. I'm experimenting with this rather than recommending it.

People might have uses for it though, especially if they have trouble getting SL. I might have uses for it too. My soaps get a lot of hand work, and I was impressed with how my tools never got gummed up when I used them with the sodium acetate test soap. Check out the pictures of the planer above. That soap looked good too. Yesterday I made some 100% coconut oil laundry soap. I included sodium acetate to make the soap behave better in the food processor and to make the shreds more brittle and crumbly for pulverizing.

Anyway, you can try for yourself and see what it does for you. Also read old threads on sodium lactate.

 

[CaraBou]

Perfect, thanks. I always wonder if I'm missing something when I don't add this and don't add that, but my desire to make a relatively simple soap usually prevails. I do add sodium citrate to reduce scum. Up until now I've done that by adding citric acid and extra lye, but my CA supply finally dwindled so I just ordered sodium citrate to be more direct. It wasn't a lot of extra math but I am looking forward to the simplification none-the-less. I have enough to worry about with all of the other variables.

Your trim job is impeccable! I can totally see why you'd prefer the sodium lactate to get that result. And I get what you're saying about the gunk when planing. I usually just try to wait longer, but I certainly have my own patience demons so that doesn't always work. Plus, when I saw the shavings, my first thought was how well the sodium lactate would make curls for decorations. I have not yet incorporated curls, but my whole "simple soap" attraction sometimes goes out the window when it comes to design. It is nice to see ways to be more successful when you start messing with the basic properties of soap :mrgreen:

 

[Saponomancer]

Out of curiosity do you remember the sources for where you read about sodium acetate acting like sodium lactate?

 

[topofmurrayhill]

Out of curiosity do you remember the sources for where you read about sodium acetate acting like sodium lactate?

Yes there's a link to the main source in the first post of the new thread.

http://www.soapmakingforum.com/showthread.php?t=59148

 

[biarine]

Interesting experiment I will try them

 

[NataliaRuth]

Please see the previous post for how to do the numbers if you want to experiment. Here are a few notes about heat.

So far I've made two sodium acetate batches. The first was an average recipe with a 33% lye, no discount, and an SA usage rate of 2.7%. The second was a coconut oil soap (which requires more caustic) with a 35% lye, no discount and an SA usage rate of 1.5%. Usage rates are in terms of a 60% solution, for comparison with sodium lactate. The starting temperature of the materials was in the mid to high 60s F.

For both of those initial batches, the temperature of the solution topped out pretty close to 200 F from dissolving the lye and neutralizing the acetic acid. The boiling point of lye is on the high side:

25% 234 F
30% 240 F
33% 245 F
40% 262 F
50% 288 F

I think this technique is fairly safe from boiling over across many typical recipes, lye concentrations, sodium acetate amounts and environmental conditions. However, it's impossible to anticipate every combination of variables and every mistake that could be made. Also, using a stronger vinegar allows for more concentrated lye and/or greater amounts of sodium acetate, which increases the hazard.

Use cold water and vinegar. You can even put them in the fridge. If you are doing anything that could possibly be outside of the envelope, don't add all the caustic at once. Allow cooling time between additions.

Hello. I'm going to try this experiment. But I have a few questions if you don't mind.
You prepared the water with the 60% acetic acid solution and then you start dissolving the NaOH in it?

I had the information that the order is "acid over base" but the times i tried to do this with citric acid to form sodium citrate, I've tried to dilute the citric acid (powder) in the lye solution and it didn't dissolved. Then I tried to dilute citric acid powder in some water, and add this (very carefully) to cold lye solution and it worked but not as good as the 3rd situation that was dissolving first the citric acid in the water and then add the NaOH.

How do you think is best for the acetic acid?

I would also like to try to add citric acid and acetic acid to produce S acetate and S citrate at the same tme, for the same soap. But i am afraid that if I add the NaOH to the water with both acids the reaction would be extreme. What do you think?

 

[Relle]

Hello. I'm going to try this experiment. But I have a few questions if you don't mind.
You prepared the water with the 60% acetic acid solution and then you start dissolving the NaOH in it?

I had the information that the order is "acid over base" but the times i tried to do this with citric acid to form sodium citrate, I've tried to dilute the citric acid (powder) in the lye solution and it didn't dissolved. Then I tried to dilute citric acid powder in some water, and add this (very carefully) to cold lye solution and it worked but not as good as the 3rd situation that was dissolving first the citric acid in the water and then add the NaOH.

How do you think is best for the acetic acid?

I would also like to try to add citric acid and acetic acid to produce S acetate and S citrate at the same tme, for the same soap. But i am afraid that if I add the NaOH to the water with both acids the reaction would be extreme. What do you think?

This person hasn't been here in 4 yrs, if you look àt the date, this thread is 9 yrs old, start a new thread to get your answer.