making liquid dish soap using a bar soap recipe

[Liesel Atwood]

Hi there! I need a little advice with a liquid dish soap recipe. I found a recipe for dish soap that is supposed to be more gentle on the hands. But it's a solid dish cake soap.
I would like to use the same recipe but use a dual lye combination and maybe add a bit of glycerin. My question involves the stearic acid in the original recipe. I won't want this in a liquid
soap, is that correct? So should I replace the amount of stearic acid with more coconut oil? I will leave the recipe, and if anyone is able to improve on it or make suggestions,
i would be so grateful. CP soap is what I do the most. I have made liquid soap, but this is my first liquid dish soap with a SF of 0, with the intention of making it gentle by using sunflower oil. I hope the end result will still be more gentle on the hands, as the person requesting it has very sun damaged skin that is sore.
Dish soap recipe in solid cake form:
Coconut oil 70%
Sunflower oil 23%
Stearic acid 3%
Castor oil 4%
SF 0
Lye concentration 36.36%
So I was thinking to replace the stearic acid with 3% of one of the other oils.
dual lye....KOH to NAOH. 70% : 30%
Does this look okay? Should I add a bit of glycerin to help the KOH dissolve?
Should i use KOH only, rather than a dual lye solution?
Should I scrap this recipe altogether and search for one that is already liquid and known to be less harsh?
All opinions and suggestions are gratefully accepted. Many thanks!

 

[DeeAnna]

I personally think the recipe author is kidding their audience -- a soap that's 70% coconut oil is not going to be particularly gentle. Especially at zero superfat (or even 5% superfat.) It will do a better job of cutting grease than a soap low in coconut though.

Yes, you can omit the stearic acid and sub one of the other fats in its place.

If this is your first batch of liquid soap, keep it simple, Soaper. In particular, I don't see much point to using a dual lye solution -- I'd use KOH only. The claim of using dual lye is that the sodium contributed by the NaOH makes the soap thicker. With 70% coconut, this recipe is going to be tough to dilute to a honey-thick syrup because there's not enough oleic acid in the blend to thicken well with sodium -- whether you add it as NaOH in the initial soap paste or by thickening the soap later with sodium salts (example: table salt).

As far as the total water content -- remember you're making a hot process soap and you're going to be diluting that soap paste with water later on. So you gotta switch your thinking to hot process soap making, not cold process bar soap. Although any hot process soap, including liquid soap paste, can be made using a 36% lye concentration, the usual suggestion is to use a 25% lye concentration (3:1 water:lye ratio) instead.

Glycerin does NOT help KOH dissolve. It makes it more difficult. I recommend always dissolving KOH in water alone. You'll find it dissolves real fast and easy. The reason why glycerin is used in liquid soap making is that it accelerates the saponification reaction of the KOH with the fats.

Dissolve the KOH in at least an equal weight of water. You can use more water than that, but don't use less water -- the KOH may well not dissolve.

Add sufficient glycerin to the KOH-water mixture so the combined weights of glycerin + water equal the total water called for to make the soap paste. I have used 1/3 glycerin, 1/2 glycerin, and 2/3 glycerin (with the rest being water). As well as no glycerin at all (all water). All these mixtures of water and glycerin make fine KOH soap, but using some glycerin makes things go easier.