Home Cosmetic Science Talk Formulating Triethanolamine & AHA’s

  • Triethanolamine & AHA’s

    Posted by Feelgoods on October 21, 2019 at 7:48 pm

    Hello Everyone! I am curious how much TEA is normally needed to raise the pH of a product.

    Created a toner with 8% Lactic/4% Glycolic acids (active %), which read a pH of 2.95 with 2.5% TEA, and a pH of 3.4 after 5% TEA.
    I am trying to maintain a pH level of 3.6-3.7, and was just a little surprised how much TEA was required for this specific formula.
    Using an Oakton pH Testr 30, which is calibrated.

    Thanks in advance!

    LincsChemist replied 4 years, 7 months ago 4 Members · 3 Replies
  • 3 Replies
  • Gunther

    October 22, 2019 at 3:08 am

    You can do some stochiometry math to find out how much TEA do you need to neutralize acids
    then you can so some pKb math to find out how much TEA is needed to rise pH once the free acids have been neutralized.

  • EVchem

    October 22, 2019 at 7:06 pm

    the acids you have have pretty low pka (~3.8) and TEA isn’t actually that strong of a base. I’ve heard that TEA is used predominantly because you have a larger ‘window’ to add it without overshooting desired pH. You should be able to use NaOH in it’s place for a toner

  • LincsChemist

    October 23, 2019 at 7:44 am

    I don’t know where you’re planning to sell this product, but it’s worth bearing in mind that the maximum permitted concentration of TEA in the EU is 2.5%

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