Lowering ph

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isha

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Hello all,
I was wondering. Ppl who make shampoo out of koh based liquid soap.. What is the best way to lower the ph..

I tried adding citric acid after dilution and it was a mess..
The paste turned white and clumpy. With a very sticky residue.
I tried a batch with direct additiin of citric acid it thinned the paste didnt dissolve well. Put it on a double boiler. Still didnt dissolve.

Another batch with 50/50 citric acid solution and tat too was a mess.
The current ph is around 9.

I want to get it pH down to 4-4.5
If i decide to use citric acid in the initial stage of soaping.

What wud be the recommended %?

With this current test. The ph did come down to 4.
For 100 gm diluted soap i added 4gms of citric acid.
So 0.04%
Appreciate if someone cud shed a littlw more light on it
 
This ia how they turned out
IMG_20180607_031812.jpeg
 
...What is the best way to lower the ph.... I want to get it pH down to 4-4.5...

You're trying to do the impossible. Soap is defined as the salt of weak fatty acids and a strong alkali (NaOH or KOH). Soap will ALWAYS be alkaline and its normal pH range is about 9 to about 11. If you try to reduce the pH of a soap below its normal pH, the soap will break down chemically and will no longer be soap. That is why your soap turned white and clumpy -- that is fatty acids you are looking at, not soap anymore. If you must have an acidic cleanser at pH 4 to 4.5, you will have to use synthetic detergents, not soap.
 
You're trying to do the impossible. Soap is defined as the salt of weak fatty acids and a strong alkali (NaOH or KOH). Soap will ALWAYS be alkaline and its normal pH range is about 9 to about 11. If you try to reduce the pH of a soap below its normal pH, the soap will break down chemically and will no longer be soap. That is why your soap turned white and clumpy -- that is fatty acids you are looking at, not soap anymore. If you must have an acidic cleanser at pH 4 to 4.5, you will have to use synthetic detergents, not soap.
Yes ,,, true i do understand the chemistry point of view of it..
Latey ive had many ppl tell me tat they reduce ph to 4 and use it as shampoo..

They say adding citric acid did work for them.

This was a small experiment to verify their words.

I wudnt want to mention names. But a lady here. Is teaching how to make koh based liquid shampoo... And claims to have ph of 5.
Many of her students contacted me complainin hair fall issue. And now shifted to ayurvedic hair oil.. N my mild surfactant based cleanser
 
Citric acid -- a little goes a long way. I use citric acid (20% solution) at a rate of o.o6%. I add it after dilution and after a 2-week sequester. It almost always "flakes out" when I add it in, but warming the soap and stirring gently with a spoon incorporates it into the batch. This brings the pH down to about 8.5. I'm not inclined to go any further than that. My understanding is that nasties won't grow in in soap that is an alkaline solution.

If you're making a syndet, I can't help with that. :)
 
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Yes ,,, true i do understand the chemistry point of view of it..
Latey ive had many ppl tell me tat they reduce ph to 4 and use it as shampoo....

Well, now you know this claim is false both from your studies and from practical experiments.
 
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