Liquid soap using sodium hydroxide
I've even thought about grating some soap and diluting it with water to see if that can be used in a soap pump, but never got around to doing it. So I was thrilled when I came accross a recipe for liquid soap that listed good old NaOH rather than KOH as an ingredient. I was a bit skeptical at first, thinking that it might just be a mistake. It actually turned out to have been one, but it was explained that the writer had made the soap, both with NaOH and KOH and liked the NaOH better. So I decided to go for it.
The recipe was on a website called The Little House in the Suburbs and it contained coconut, canola and vegetable shortening. I fully intended to follow that to the letter (apart from the fuzzily defined vegetable shortening which I can't get here) but circumstance led me to have to devise my own recipe. The only oil I had was a dark Olive oil so I used that and coconut oil. The original seems to be pure white and I like that, so I will make another batch soon with white oils. When I was going to make mine it was 3 o'clock in the morning and the internet wasn't working, I could only load Icelandic sites, but no foreign sites. This was probably due to some Scottish farmer plowing his field and taking the cable in two (you'd think there were more sophisticated explanations to technological failures!). So I couldn't use Soapcalc and I wasn't about to start to compute lye at that hour. The solution was to use an old recipe and measure exactly.
The recipe I used was:
122 g /4.3 oz. coconut oil - 30%
298 g /10.5 oz. olive oil - 70%
250 g / 8.5 oz water - this is quite a bit more than usual - about 60% of oil weight
56 g / 2.1 oz lye - I allowed for about 5% SF - which might not be necessary in dishwashing soap.
The process is the same as usual CP. When the oils and water have been combined the whole thing is insulated (I don't usually do that with CP) and left for 24 hours. I put the soap in a large stainless steel pot and just shoved it in the cold oven and left it there. The next evening I started to add more water to it. A cup or so at a time up to 1.5 liter. First I did this in the oven at a temperature of 105-120 C and stirred it in a little bit. When it was starting to look liquid and smooth I put it on the stove and heated gently and added more water and stirred. There was a bit of foam on the top, so I just skimmed that off and threw it away. When I felt the soap was the right consistency I let the whole thing cool a bit and added lavender and peppermint EO and then poured it into bottles.
I like the soap. It feels nice on the skin and it hasn't clogged the soap dispenser yet. My daughter doesn't like the colour, but it's very olive-oil-soap-green so I figure that can't be bad.
Update: I think this could be diluted a bit more. I also put it much diluted into a foam dispenser and it works beautifully in that. Soft, soft foam. Much better than what was in there before.