Salting out for Laurndry soap

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boyago

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So I want to make some laundry soap from all my old not so great soaps and scraps. I figured I'd do the brine boiled soap to get my base. Looking for confirmation of my suspicions that this will boil out the SF I can only find that it will take out the glycerine and excess lye. It will right? I haven't found a clear salt to water rate for the brine.
Also I keep finding the rate of 2C soap shreds to 1C washing soda + 1C Borax but one of the links takes me to a page that states powdered laundry should or is either washing soda or borax and that borax works in liquid but is not useful in powdered. Any opinion on this? Then some use an oxyclean type powder at a 1/4C to either Borax or Soda.
So those of you who do their own Laundry powder what rates are you using?
 
All kinds of scraps, I know that the ideal would be something like straight CO or PKO with a high cleansing attribute but I'm also looking for a use for the scraps and willing to loose a little of the cleaning POW for that purpose. Or do you think that would be an exercise in futility? I figure it will still work relatively well.
 
I am using laundry soap CO 100% with 0 SF, and I do not advice to use soap scraps, the oils in soap will seap into your clothes, and I am not sure your washer will like it.
DeeAnna uses just CO soap same as mine with washing soda. I will make some omitting borax.
Search the forum "laundry soap" you will find a lot of info
 
Hmmm. Okay, so here's a thought -- why not do a "rebatch" on those scraps and add about enough lye to bring the scraps to an estimated zero superfat, give or take a bit? This doesn't need to be super precise, cuz it's laundry soap, not bath soap, and it's even okay to be a little lye heavy if you want to err in that direction. This gets around the troublesome issue of boiling soap with lye and salting it out and all that jazz.

Here's an example:

I'm guessing your scraps come from typical recipes may be something like 80% tallow, lard, olive, sunflower, palm, etc. and about 20% PKO or coconut.

The average sap value of the non cleansing fats (tallow, lard, olive, sunflower, palm, etc.) is very roughly 0.136 and the sap value for the cleansing fats (PKO or CO) is 0.180 or thereabouts.

What is the estimated overall sap value for the fats in your scraps?
80 / 100 X 0.136 + 20 / 100 X 0.180 = 0.145 g NaOH / g fat

Let's assume you have 3 pounds of scraps. Since I don't do soap in pounds, how many grams is this?
3 lb X 454 g/lb = 1362 g of scraps

And if your typical superfat is 8%, how much fat is in those scraps?
8 / 100 X 1362 = 109 g

How much lye is needed to saponify that fat?
109 g fat X 0.145 g NaOH/g fat = 15.8 grams NaOH

So now do a rebatch and add about 16 g NaOH to the liquid you expect add to soften the scraps. Stir the liquid in very carefully wearing the safety gear you usually wear (or not, since I seem to remember something about you, Boyago, not wearing safety gear). In any case, just be aware you're more likely to get splashes doing this. Heat until the soap is softened and the liquid is thoroughly mixed in. Pour in a mold and Voila! laundry soap.

I am currently trying out equal parts by weight of soap and washing soda with oxygen bleach (oxyclean clone) as needed. My whites are slightly whiter than when I was using the 1/4 soap, 1/4 baking soda, 1/4 washing soda, and 1/4 borax recipe (again w oxygen bleach as needed). I also think I'm getting better removal of greasy stains without as much pretreatment. The article written by the gal who did all the study about what does and doesn't go into laundry detergent was very convincing, and my experience seems to be in line with what she says.
 
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since I seem to remember something about you, Boyago, not wearing safety gear


Moi?!? I rock my PPE, not as diligent as I should be but I wear my gloves and goggles. I posted a pic of my eye burn but that happened while cleaning up the morning after a late night soap happening when I thought I was safe enough.

If I go the re-batch route which seems like a pretty good idea would there be any benefit to using KOH instead of NaOH? My guess is it would dissolve a teensy bit better.

Also Deeanna, is your ratio by volume or weight?
 
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But also a reason to boil out the soap would be for all the other junk I throw into soaps. oat meal, kelp, sugar and such. Best to get some of that junk out.
 
My apologies ... think I've confused you w someone else who has confessed his sin of not doing the gloves and goggles routine!

I do everything by weight even my laundry soap mix. The original four part recipe was by volume but I converted it to weight for consistency.

If you want to clean out the additives then yes you're looking at boiling and salting. The reason why you won't find measurements of the salt is that there aren't any. The amount of salt depends on the fatty acids in the mix. More lauric and myristic, the more salt. The more oleic, stearic, palmitic, or linoleic, the less salt.

edit: Here's another thread on the salting out process: http://www.soapmakingforum.com/showthread.php?t=32717

Sent from my KFTT using Tapatalk HD
 
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With boiling and salting ONLY use NaOH. KOH soap is too soluble in water, salty or otherwise. You cannot salt out a KOH soap.

Sent from my KFTT using Tapatalk HD
 
If you want to clean out the additives then yes you're looking at boiling and salting. The reason why you won't find measurements of the salt is that there aren't any. The amount of salt depends on the fatty acids in the mix. More lauric and myristic, the more salt. The more oleic, stearic, palmitic, or linoleic, the less salt.

Sent from my KFTT using Tapatalk HD

I already did the salting out (which was pretty fun) but was just thinking, could I do both? In the first boil add the necessary (plus some) NaOH to the boil (do a long first boil light on the water) and then salt out? Wouldn't that make more soap out of the SF and then just rinse the extra lye out with the rest of the junk? Kind of a quazy boiled soap/rebatch.
 
"...add the necessary (plus some) NaOH to the boil (do a long first boil light on the water) and then salt out?..."

Yep, I agree -- that is what you'd want to do to get a zero superfat product.

Bear in mind that a concentrated lye solution will also "salt out" soap, so to get the best saponification, you'll want to add lye to the soap at a relatively low NaOH concentration and boil the combined mixture to saponify the excess fat. What is "relatively low NaOH concentration" will vary depending on the soaps involved. I'd experiment with a 25% NaOH solution concentration with the idea of adding more water to reduce the lye concentration if it looks like the soap is remaining separate from the lye.

Some other thoughts:

Boiling, passing live steam through the soap mixture, and mechanical agitators are used by large-scale soapmakers to keep the soap mixture well blended. A whisk or stick blender will be a good substitute for a rolling boil and live steam. :)

Once you think saponification is done, salt out the mixture to cause the soap to separate from the water phase. Separate the soap phase from the water phase, however that works best for you -- I'd probably pour the whole mess into a strainer and let the water phase drain out. Give the soap curds a good spray with cold water to rinse off more of the "spent lye".

Return the soap to the "soap kettle" and add more plain water if you want to further wash the soap. Boil to mix the soap and water, salt out, and separate the phases.
 
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Okay, well here is what I did. Keep in mind I am not an expert and most of the information here is just regurgitated from other threads on this site and a couple other places I poked around on the internet. But this is what I did and what I would do differently next time. Though my goal here was to make a laundry soap I was also trying use up the scraps, odds, failed soaps and experiments I’ve done. Most of the soaps that went into this were old soaps from my first year of soaping. If you are wanting a super well performing dedicated laundry soap as has been mentioned you are probably better off starting from scratch and making a CO soap base to work with. But here it is.
1. I came here and asked a couple questions. DeeAnna had some really good advice about not boiling it out but doing a re-batch to saponify the SF in the soap. I however did not follow this advice because my soaps were all full of junk. There were some with clays, big chunky pieces of oatmeal and whatever else I thought of trying in soaps. So I thought I should just boil them up to clean this stuff out. After I did my first boil however I realized I could have done both, by adding additional lye during the first boil. To do I should have / will in future calculate a general SAP value for my super fatted oils. In going over my notes these soap where either straight up Castiles and Bastiles so I am good with using the rounded SAP values DeeAnna posted above as .136 & .180. So almost all of these soaps were an 80% to 20% olive or RBO to CO my average comes to .145. So in my case I wound up using 750g of scraps. All of these soaps were done with soapcalc at the default setting of 5% SF. The 750g x .08 = 60g of SF in my scraps. 60g x .145 = 8.7g of NaOH to add to my first melt and boil to tidy up the SF. If you take into account that there are non-soap solids in my soaps (the clays, oats, sugars ect) and I made the NaOH calculation based on the weight of my scraps you may note that this is actually a little high since the weight of the additives in there too. Sine I am boiling it, it will come out and I’m not bothered by this. I will throw this NaOH into enough water to cover the soap and do a long first boil, maybe 40 minutes.
2. I collected up a bunch of my old soaps and dusted off the salad shooter. I’ve only got the one cutting insert for my shooter (thrift store score) but if you have another shredder or are doing it by hand the thinner the shreds the better. There is something about shredding soap that I find very zen. Even with the loud whirring of the shooter it is very calming. If I had to do this by hand I may not feel the same way.
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3. The first boil is where I made a mistake. For some reason I was thinking that I was just supposed to boil the soap in a brine. This is not the case. When I did this the soap got to its melting point and then just hung out on top of the brine I had mixed and added to the pot first. The right way is to add just water let all the soap dissolve and then add the salt till the soap and now brine water decide they don’t much like each other and the soap separates from the brine. It makes sense when you think of it like the whole thing is called “salting out the soap” you’re salting the soap out of the water. Though I did it wrong the scrap soap did drop allot of the junk into the brine. After 20-30 minutes I started scooping the soap curds out with a slotted spoon into a strainer to cool down.

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The soap being not entirely solid did press itself through the holes in the strainer (big holed spaghetti type not the screen type) and made short soap noodles which were kind of fun to shear off with my hand. It was around here when I realized that my strainer was pretty much a perfect fit for the pot I was using so I planned to throw it in the pot before the next boil and I could just let the soap cool and just lift it out when it was cool.


4. For the second boil after the soap had mostly cooled down I broke it up threw it back in the pot and covered it with fresh (non-salted) water. I did about equal parts by volume and melted it back down again. I placed a lid on the pot and told myself that I was being impatient and to make sure to sit there with it as covering the pot would cause the soapy solution to boil over and make a mess. I then saw something shiny, a squirrel or something with pretty buttons and let the soap boil over onto the stove causing a huge mess. After stirring the suds back down and reducing the heat I kept it at a low boil for about 20 minutes and started salting.
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I didn’t measure the amount of salt I used but it just became apparent when the soap was lifting out of the brine. This time the soap curds were much cleaner looking than the first time through. It was getting late so I just let the soap cool down for an hour or so then lifted the strainer out of the brine and slipped a long spoon through the handle to hang the strainer over the brine and threw the whole thing in the fridge.
5. The next morning I took everything out of the fridge and popped the soap out of the strainer.
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I then took a trip to Medford to stay with my aunt and uncle to show Soapcutter the ranch and let her help with the animals. It was a really nice trip and Soapcutter had a blast, got to ride a horse, quad and the tractor!
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6. When I got back I cut up and shredded the mass of now cleaner soap. The shreds felt kind of damp still so I spread them out on a cookie sheet and put the fan on them. I turned the shreds whenever I passed through the room and they felt dry enough after a few hours but I went ahead and left them there with the fan on low over night.
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7. The next day I looked at a few different laundry soap recipes and settled on by weight 50% soap shreds, 25% washing soda, and 25% equal parts borax and an oxy clone. I used the metal chopping blades in my food processor to grind and mix everything together. My processor could only handle about half of the soap I had at a time so I made two batches. Each batch got about 20 drops of Eos for scent.
 
How it clean? More better than coconut soap with 0%SF?

No. A straight coconut soap would be the way to go if your going to make a soap specifically for cleaning, but I was trying to get some use from soaps that would otherwise just be a waste.
 
No. A straight coconut soap would be the way to go if your going to make a soap specifically for cleaning, but I was trying to get some use from soaps that would otherwise just be a waste.


Thanks I thought will be more cleansing than cp or hp
 
Boyago -- you are a bad, bad influence. I wasted :) my time this afternoon on boiling and salting out my soap scraps. Here's my adventure:

1. I collected a bunch of soap scraps and coarsely ground them in my food processor. You can see the bag full of scraps in the first picture. The total weight of scraps was about 1000 g. In an old pot, I added 500 g of distilled water and 10 g of NaOH (to saponify any superfat) and brought that to a gentle simmer. I then added handfuls of scrap, stirring well between handfuls. I tried to keep the temperature above 190 deg F but low enough that the soap was content to stay in the pot rather than boil over.

2. The scrap and water mixture looked like nasty thick gravy when I was done. I used my stick blender a little bit, but it was mostly stirring with my trusty spatula. As I worked, I realized that the soap was sticking to the bottom of the pot a little bit. I only added a little more water and basically put up with the problem, but I now know that I should not have scrimped on the water. I should have added distilled water up to the weight of the scraps (1000 g) -- or whatever was needed to keep the soap from sticking.

3. Once the soap was fully melted down and smooth, I cooked it at a gentle simmer, stirring frequently, to allow the NaOH to saponify any free fat. After about 20 minutes of cooking, the soap didn't zap, so I figured it was time to add the salt.

I started with table salt, but switched to rock salt (scavenged from my water softener!) when I realized I didn't have enough table salt to do the job. The table salt dissolves faster, but rock salt is fine if you don't mind stirring longer to get it dissolved.

For scraps that are the usual blend of fats typical for bath soap, I figured the salt should be 15% to 25% of the weight of water added to the scrap. For this batch, that would be 150 to 250 g. I added the salt in 3-4 additions, stirring well after each addition until the salt dissolved.

4. I watched the soap appearance change as the salt content rose. It began to separate into a dark watery layer underneath a curdled soapy layer. I only added about 150 g of salt, and I don't think that was quite enough salt for this first pass. The soap certainly separated as you can see in the photo, but the soap never "grained out", meaning it didn't become as chunky (like cooked oatmeal) as it did in the second pass. I think it needs to look more like oatmeal. Once you get to that stage, stop adding salt. The weights are just guidelines, and every batch will be a little different.

5. I let the soap and water mixture cool until the soap started to harden up. I poured the soapy mass into a colander (sieve) lined with cheesecloth to drain. The water that drained from the colander was dark brown.

...to be continued....

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6. After draining as much of the water out of the soap as I could, I added about 500 g of distilled water to the pot, added the wet mass of soap, and heated the soap back to a simmer.

Although I had realized at this point that I had not used enough water in the first pass, I also realized the soap now had a lot of extra water in it, so I thought just 500 g of water was enough to raise the water content to roughly equal to the weight of the scraps.

This time the soap returned to a nice simmer fairly quickly. You can see the color of the soap is a lot lighter now than what it was at the start of the first pass.

7. I started to add salt in small additions, stirring well between each addition. I was looking for a harder, more granular appearance to the salted-out soap. As the soap started to look like curdled chunks of oatmeal swimming in runny liquid, I realized the soap was "graining" like it should.

I also saw the "roses" that the old soapmakers describe. The bubbles coming up through the "roses" make a little burbling sound; the old boys said the soap "talked" at times like this.

8. I turned off the heat and allowed the soap to cool. I realized that by stirring the soap, all I was doing was mixing the water and soap layers. I wanted them to separate, not mix! So I gently cut through the mixture to allow the soap curds to rise and the water to sink.

9. When the soap fell below the gel temperature, it hardened into a pebbly chunks that I could crumble apart in my fingers. At that point, I lifted as much of the soap out of the pot as I could with my hands and put it into my cloth lined colander.

10. The water that drained out of the soap was not as dark as the first pass, but still pretty dark.

11. The soap itself was a pleasant ivory color, so I decided I would stop the boiling and salting thing. I rinsed the soap curds with a gentle spray of cold tap water to get as much of the salt and such off. I could tell the fresh water rinse was dissolving some of the soap, so I didn't spend a lot of time on this -- I tried to find the a compromise between losing some soap vs. removing as much of the salty water as I could.

In hindsight, I should have let the rinsed soap continue to drain and dry out for at least 1 or even 2-3 days before going on to the next step. The old soap makers would let a soap settle for several days, and I now realize there is a lot of wisdom to being patient at this point. But I ignored that wisdom and moved right on....

... to be continued ...

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