Salts of Sulfated Oleic Acid Amides as Acid Corrosion Inhibitors

This work is a continuation of a series of studies on the preparation of acid corrosion inhibitors derived from carboxylic acids. A synthesis was developed for acid corrosion inhibitors derived from oleic acid amides. Several syntheses were carried out in an attempt to obtain compounds with improved corrosion inhibition properties. Aminoalcohols were added to oleic acid in the first step and the resultant products were sulfated with sulfuric acid. Reactions with bases were carried out with the aim of expanding the range of such inhibitors. Salts of sulfated oleic acid amides were synthesized by reaction with aminoalcohols, sulfuric acid, and bases in aqueous solution. The protective action in dilute hydrochloric acid was evaluated in order to establish the inhibition efficiency of these compounds, some of which appear to have suitable corrosion inhibition properties. The ammonium salt of the sulfated diethanolamide of oleic acid was found to be the most efficient corrosion inhibitor among these products.