Inhibition effect of oxalic acid on copper corrosion

This paper deals with the inhibition effect of oxalic acid on the corrosion of copper in concentrated propionic and dilute citric acid solutions. The copper samples (in acid solutions) were left in a water bath for a period of six days and were examined on a daily basis. The solutions were continuously fed with oxygen (air) and the temperature of the solutions was always maintained at 30°C. The oxalic acid in all three cases behaved like an inhibitor under the experimental conditions. The mass of the copper samples increased due to the formation of oxide layers on the surfaces of the samples.