In the technology of fats, a hydroxyl number is determined by esterification with acetic anhydrides in the presence of pyridine. You can try this technique.
I think must calculate the ZPC of catalyst surface by titration method, but I search it ............ If any one have this method, please, send me it....
Dear Luma M. Ahmed the problem here is that I have hydroxyl groups in the bulk and surface of the substance, which are reacted by the titration of these groups, but I want to determination concentration of surface hydroxyls.