Technical note Effect of corrosion inhibitors on scale removal during pickling of mild steel

Abstract

The effect of certain heterocyclic organic inhibitors (indole, indole acetic acid, indole butyric acid, and 3-acetyl indole) on scale dissolution during the pickling of mild steel in 10%HCl has been investigated by means of corrosion potential measurements and scanning electron microscopy (SEM). The results have shown that indole and 3-acetyl indole have the highest inhibition efficiencies of 98 and 96% respectively. However, while 3-acetyl indole slightly retarded dissolution of the oxide scale, indole accelerated the scale removal process.

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