You might need to acidify it with HCl (pH < 3)

Thank you Aqeel A. Hussein for your interest. Do you think I need reflux?

I don't think you need reflux. I think that you just need to add some ethyl acetate and little water, and then start adding HCl into solution until pH becomes less than 2 using pH paper. Its is in a similar way to the hydrolysis of ester using NaOH/H2O, in which you acidify your solution before extraction.

What is the role of ethyl acetate @aqeel hussein

In order to extract the acid into organic phase to make tow layers.

The general method to convert your heterogeneous sodium carboxylate to a free carboxylic is by adding dilute HCl (1 or 2 mol/litre). You could do that by following any ways of bellow, the main thing you have to be very careful about is the concentration of HCl and the quantity don’t add too much and follow up the solution after each addition by PH paper because it might form lactone.

A) Take heterogeneous sodium carboxylate extract with diethyl ether to remove any impurity, then add dil. HCl to PH= 4. Then extract the solution with ethyl acetate and the reason for this to get the acid.

B) B) Add water to heterogeneous sodium carboxylate then add dil. HCl dropwise, stir the solution for 10 min. the extract the solution with ethyl acetate



Thank you, Aqeel A. Hussein and Aula Ali , for your true support

I understand/guess your material is a sort of an ion-exchange resin in its Na+ form. You have been rightly suggested to treat that with dilute HCl solution.

Depending upon the quantity, you may take your material in a column of appropriate dimension (diameter and length) and then charge the column with dilute HCl from top. Monitor the pH of the liquid coming out of the column from its bottom. Completion of exchange should be indicated by acidity of the out-going solution from the bottom of the column.

With best wishes,