ELECTROCHEMICAL AND ECLIPSOMETRIC STUDY OF IRON CORROSION INHIBITION IN SODIUM-SULFATE SOLUTIONS CONTAINING ALIPHATIC-ACIDS

The inhibition effect of normal aliphatic acids with 6-10 carbon atoms in the molecule has been investigated in aerated solutions of 0·05 m sodium sulphate at 6-12 pH. It was found that the depolarization of oxygen is not the only factor responsible for the passivation of iron in aerated solution containing a critical concentration of the inhibitor. The inhibiting ability of aliphatic acids in Na2 SO4 solutions is brought about by a synergistic action of dissolved oxygen and of molecules (or anions) of the aliphatic acid. © 1979 Chapman and Hall Ltd.