I am attempting an extraction largely following the Lextek. I have made some minor alterations in technique based on the equipment I have, most notably the use of a seperatory funnel. All the steps seemed to be going as planned until I got to the point in the defat procedure where the solution was re-basifiyed. After adding the NaOH I had a mostly clear solution with some white precipitate. To ensure this white solid was not simply undissolved NaOH I added more water and stirred thoroughly. The precipitate persisted and so I thought, "great, this must be my product." However, after doing 3 warm naptha pulls seemingly none of the precipitate dissolved. When the mixture was allowed to sit in the sep funnel and separate, this white stuff settled right in between the two non-miscible layers. Is this the stuff I need to be saving or is it some kind of impurity?

Up to now I have not done a freeze precip on my final naphtha pulls and so I cant say for sure what yield actually is dissolved in it. Thanks for the help.

Did you happen to replace acetic acid with sulphuric acid for the extraction?

You may have accidentally made sodium sulfate, which is not very soluble in water at all:

4.76 g/100 mL (0 °C)
42.7 g/100 mL (100 °C)


2NaOH + H2SO4 => Na2SO4 + 2H2O