Home Cosmetic Science Talk Formulating Dishwashing Liquid

  • Dishwashing Liquid

    Posted by ChE28 on October 4, 2023 at 7:27 pm

    The dishwashing liquid that I formulated became cloudy and produced a foul odor when it was diluted with water. I am from the Philippines, and the norm here is that dishwashing liquid is commonly diluted with water to be used for a longer time. What could be the reason for this foul odor? The formulation has SLES, Glycerine, Sodium Benzoate, NANSA, CDEA, Colorant, Sodium Chloride, Sodium Hydroxide, Benzalkonium Chloride, and Fragrance. But for the record, even if it is not diluted, upon observation after 2 years, the dishwashing liquid became cloudy and the pH also declined.

    LeonB replied 1 week, 2 days ago 5 Members · 8 Replies
  • 8 Replies
  • philgeis

    October 5, 2023 at 1:44 am

    Very likely, microbial contamination.

  • ChE28

    October 5, 2023 at 4:36 am

    Thank you for your reply. But even if it is not diluted, the solution becomes cloudy and has a foul odor after more or less 2 years.

  • ketchito

    October 5, 2023 at 7:58 am

    Another possibility is that you have an alkylbenzene sulfonate (NANSA), which was formed by neutralizing a type of sulfonic acid with sodium hydroxide. This results in an equilibrium. Since water is part of the products, by adding water (dilution), the system will reform the acid, which is less soluble than is salt. Also, some flagrantes are not stable in acid environments (that might be your foul odor). Check the pH of your 2 year bottle, to see if the pH dropped.

  • ozgirl

    October 5, 2023 at 4:16 pm

    It sounds like microbial contamination.

    Benzalkonium Chloride (cationic) is not compatible with your anionic surfactants.

    What is the initial pH? It needs to be around pH 5 for the sodium benzoate to be effective as a preservative.

  • ChE28

    October 8, 2023 at 10:32 pm

    Thank you so much for all your replies. 😊

  • LeonB

    November 20, 2023 at 7:18 am

    Hi there,

    Please can you add UREA to the formulation (this should clarify your product although it will decrease the viscosity a bit. Please remove the Sodium Benzoate and try to obtain a blend of CIT & MIT if you can. When you obtain the correct preservative then also allow for the product that when diluted that the preservative is still active within the suggested active percentage in your formulation. Always check your pH it is important - try for a pH of about 5 @ 25°C

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