AN INVESTIGATION OF COPPER CORROSION INHIBITION IN CHLORIDE SOLUTIONSBY BENZO-HYDROXAMIC ACIDS

Benzo-hydroxamic acids (BHA) are investigated as potential copper corr osion inhibitors in chloride solution. The BHAs investigated were: p-c hloro-benzo-hydroxamic (p-Cl-BHA), o-chloro-benzo-hydroxamic acid (o-C l-BHA), p-nitro-benzo-hydroxamic acid (p-N-BHA) and o-methyl-benzo-hyd roxamic acid (o-M-BHA). Electrochemical measurements, potentiostatic p olarization and ac impedance spectroscopy were carried out to evaluate the inhibition effect of the investigated BHAs. An Electrochemical Qu artz Crystal Microbalance (ECQM) was used to measure electrode corrosi on and inhibitor adsorption or layer formation processes. A poorly sol uble layer consisting of the inhibitor and copper corrosion products i s proposed to account for the protective effect in chloride solutions. (C) 1997 Elsevier Science Ltd.