Floaty matter on top of soap that likely isn't oil

Discussion in 'Liquid Soap and Cream Soap Forum' started by Sapo, Jan 2, 2018.

  1. Jan 2, 2018 #1

    Sapo

    Sapo

    Sapo

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    Formulation:
    -coconut oil (SAP value 265 used)
    -olive oil (SAP value 196 used)
    -KOH (tested at 43.8% concentration)
    -distilled water
    3:1 water:koh ratio

    This soap was formulated using the high end of the SAP value range, to be certain of complete saponification, with the realization that a potential for a slight KOH excess is possible (in fact, it is likely and expected).

    After dilution, the whole thing was cloudy (sorry, no pictures) which didn't quite make sense (i now realize it was basically because of this floaty matter being dispersed within the soap - if i mix it now, its cloudy again). After a 2 week sequester, it is as clear as water:
    [​IMG]

    Now here is my question... Since it doesn't seem feasible that whatever is floating on top is unsaponified FFA/oils...what is it?
    (picture time):
    [​IMG]
    [​IMG]
    [​IMG]

    Also; when I put a drop of 0,5% citric acid solution on it, it definetly reacts (on a pure potassium cocoate soap the reaction is instant, but as seen in the video, on a pure potassium olivate soap, the reaction is somewhat delayed, but equal).

    The rest of the pictures that I wasn't allowed to include in the first post:

    [​IMG]

    The video of adding 5 ppt citric acid to the soap:

    https://youtu.be/8mtAePXcKo8

    The material is more scaly in nature than unsaponified oils usually are, and on top of that, it seems to stick towards the edges.

    Could it be that excess lye tends to float on top and thats what im dealing with here?
     
  2. Jan 2, 2018 #2

    Sapo

    Sapo

    Sapo

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    In contrast, here is a soap formulated with reverse logic in mind, using the LOW end of the SAP value for each oil (thus assuring that there is zero possibility of a lye excess). All ingredients/batches identical.

    You can clearly see unsaponified FFA/oils being suspended within the soap at the UPPER HALF of the bottle. 2 weeks of sequestering have not made it settle to the bottom or top as of yet. With a more concentrated or dilute soap, I suspect it would all either rise or fall.

    Note: the entire soap used to be riddled with these particles, but I've added 10 or so drops of ~50% lye solution into it, and clearly the bottom half of the particles got saponified and disappeared (the lye tends to form a solid white mass that looks like a giant rain drop when added to the soap, and sinks to the bottom. Eventually dissolves).

    [​IMG]
    [​IMG]

    I tipped the bottle on it's side to show how the unsaponified particles move around:

    [​IMG]

    And then back up again:

    [​IMG]
     
  3. Jan 2, 2018 #3

    Susie

    Susie

    Susie

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    My theory (without being able to touch and test it myself, it is just a theory) was that you have some unsaponifiables in there from the OO. However, when you added additional KOH/water, they fell to the bottom and then disappeared tells me that it is FFA/oil. No matter what you thought your KOH purity was, it was not. You need more KOH/water to clear the whole thing.
     
  4. Jan 2, 2018 #4

    DeeAnna

    DeeAnna

    DeeAnna

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    It's hard to say for sure, but I'm leaning toward the flakes that don't disappear when you add KOH as being unsaponifiable solids from the fats. Not fats. Not fatty acids.

    The point of sequestering is to let any odds and ends either settle or float and then skim the floaters and/or decant the clear soap off the settled solids. Then you can achieve the goal of crystal clear soap.

    Fats, being products of plants, can have varying compositions from batch to batch and among different types of fats. Meaning you might have this problem with some batches and not with others.

    It's not excess KOH -- a strong alkali like KOH is definitely going to remain in solution, not precipitate out. Potassium carbonate (a normal impurity in KOH) would also be fully soluble in diluted liquid soap.
     
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  5. Jan 2, 2018 #5

    Susie

    Susie

    Susie

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    Ugh, you said IN CONTRAST, and I missed it. Sorry. I should not type before coffee.

    I am going back to my unsaponifiables theory.
     
  6. Jan 2, 2018 #6

    Sapo

    Sapo

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    Just to be clear: I was adding citric acid, not KOH, to the first (high end of SAP value used) formula, thinking it might have something to do with excess KOH.

    The floaty layer is present in both 100% potassium olivate as well as in the 100% potassium cocoate in pretty much the exact same form. I suppose its possible that its unsaponifiables in both cases, albeit a bit weird.

    Testing another layered soap (100% cocoate) by adding even more KOH (even though it was formulated with an excess to begin with), just to eliminate imperfect saponification as a possibility.

    The formula where the low end SAP values were used is reacting predictably/favorably to additional KOH and doesn't seem to share the problem (scaly floaty layer) with the other formula.
     

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