100% Coconut oil or Palm oil (or 50/50 mix) with KOH (potassium) instead of Sodiu Lye

[RogueRose]

We all know the soap made of 100% Coconut oil (CO) or Palm oil (PO) (or maybe a combination of CO and PO) - not palm kernel oil/flakes - using sodium lye, is very hard. Most of us also know that using KOH (potassium hydroxide lye or caustic potash) leads to softer soaps, many of which will never really solidify unless very little H2O is used or it sits out and ages in air (dehydrates).

I'm wondering if anyone has tried a soap of the 2 oils above, either 100% of one, or a mixture of the percentages of the oils, using KOH (potassium hydroxide).

I have gotten very hard bars using olive oil and sodium hydroxide but then getting liquids when using potassium hydroxide with olive oil. Using a mix of sodium and potassium hydroxide will give varying hardness (or thickness’s if more KOH is used) of the bar when using olive oil.

What is strange is that some oils with similar fat profiles (as Olive Oil) will not get even reasonably hard when using 100% sodium hydroxide. This is what kind of baffles me and I spent the last 2-3 years studying chem to figure some of this stuff out along with other fascinating things.

So I'm wondering what might happen to a soap with 100% PO or CO (or any combo of both) with KOH. Will it be liquid(ish) or maybe a gooey sludge/slurry - or will it produce a bar as well?

 

[Arimara]

Do you know what type of soap KOH yields?

 

[DeeAnna]

No, an all-KOH recipe with 100% coconut or palm kernel oil won't make a bar soap. It makes a paste.

People do 100% coconut soap with KOH for household cleaning and laundry -- it's a no-big-deal kind of thing. Susie, to name one person off the top of my head, does exactly this. I think 100% PKO soap is less common, simply because fewer people choose to use PKO vs coconut -- price, availability??? There's no chemistry reason to not use it.

Varying proportions of KOH and NaOH are used for shaving soap and cream soap. The texture you get depends on the ratio of NaOH to KOH and to some extent also on how much water there is in the recipe.

Speaking very generally: 10% KOH or less = hard bar soap. More than 10% KOH but less than 80% = cream soap and shave soap territory. 80% or more KOH = liquid soap paste and shaving croap (soft shave soap).

Lindy has a nice tutorial about cream soap on SMF -- check the liquid and cream soap forum for the thread.

Songwind and Lee Bussey, among others, have contributed good info about shaving soaps with all KOH or a mix of both alkalis. I think those are in the lye-based soap forum, if I remember correctly.

 

[RogueRose]

I thought it would give a softer soap but with how hard 100% CO bars get I thought this might be enough to counter the softness from KOH. I'll have to give this a try and see what happens.

 

[Susie]

I can help you on the 100% CO (PKO is far too expensive!), KOH 55% and up end of this spectrum, they all end up as liquid soap paste.

I use 5% KOH in my bar soap routinely. Still gives a nice hard bar.

 

[penelopejane]

I can help you on the 100% CO (PKO is far too expensive!), KOH 55% and up end of this spectrum, they all end up as liquid soap paste.

I use 5% KOH in my bar soap routinely. Still gives a nice hard bar.

Susie,
Do you use 5% KOH in all your bar soap or just high OO ones?

 

[Susie]

I use it in all my soaps now. As you know, all of my soaps are high lard. Varying amounts of lard, but all high lard. No matter what percentage of lard, tallow, palm, olive oil, the increased bubbles are very apparent. It is like you fast forwarded time 3 months on the lather. My soaps without KOH eventually get there, but this gets it to that amount of lather in 6 weeks.