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  • Reaction with Lye causing ammonia fumes

    Posted by jiroband on January 26, 2019 at 8:38 pm

    While making a new cold process soap recipe, I noticed an intense ammonia smell when adding ingredients to my lye (sodium hydroxide) solution. I’m wondering what combined with the sodium hydroxide to produce this. (Note that this occurred to the lye solution BEFORE mixing into my oils.)

    The following ingredients were mixed thoroughly prior to adding them to a pre-mixed lye solution:

    3.0 oz Distilled water
    0.5 oz Sodium lactate
    0.25 teaspoon Allantoin
    2.0 teaspoons Niacinimide
    1.0 teaspoon Caffeine anhydrous
    1.0 teaspoon Glycine betaine
    1.0 teaspoon Xylitol

    Then I added this to my pre-mixed sodium hydroxide solution:
    3.9 oz sodium hydroxide solution(1:1 water to sodium hydroxide)

    Then . . . WOW . . . smack you in the face ammonia fumes.

    What happened?

    Any input would be greatly appreciated — thank you.
    Jim 

    jiroband replied 5 years, 2 months ago 2 Members · 4 Replies
  • 4 Replies
  • markbroussard

    Member
    January 26, 2019 at 9:05 pm

    @jiroband:

    If you want to include these additional water-soluble ingredients, I would recommend that you change your procedure.  First, a 50% NaOH solution is quite high … did you calculate the correct amount of NaOH it would take to saponify your oils?  Generally, your NaOH solution would be more in the 30% range.  But, if you use a saponification calculator, you’ll get the correct amount of lye/water to add for the specific oils you are using.

    Regardless, I would recommend that you first add your NaOH solution to the oils and saponify to a light trace and then add these ingredients after your saponification reaction is complete to minimize/eliminate reaction of the NaOH with one of these additional ingredients. 

    The most likely culprit is the NaOH reacting with Niacinamide to form Nicatinic Acid + Ammonia.  You might reconsider adding Niacinamide to this concoction.

  • jiroband

    Member
    January 26, 2019 at 10:04 pm

    Thank you for the reply Mark!

    I use “Soapmaker 3” software to calculate my lye and oils - I assure you that it is not lye-heavy. This software has a built-in adjustment for using a concentrated pre-made lye solution which adjusts lye solution requirements accordingly. I’ve been making soap with this software for over 8 years, and find it invaluable.

    Jim

  • markbroussard

    Member
    January 27, 2019 at 3:06 am

    @jiroband:

    Ok, then your problem is most certainly Niacinamide reacting with NaOH to release the ammonia, so you should probably leave it out of your concoction.

  • jiroband

    Member
    January 27, 2019 at 4:41 pm

    Thanks again, Mark. Your comments are very much appreciated!

    Jim

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