INHIBITION OF COPPER CORROSION IN 1M NITRIC-ACID WITH BENZOYL BENZALDEHYDE HYDRAZONE DERIVATIVES

The effect of substituted benzoyl benzaldehyde hydrazone derivatives o n the inhibition of copper corrosion in 1M nitric acid solution at 303 K was investigated by potentiodynamic and weight-loss measurements. A significant decrease in the corrosion rate of copper was observed in the presence of the investigated compounds. The corrosion rate was fou nd to depend on the nature and the concentration of the inhibitors. Th e Tafel slope is approximately constant independent of the concentrati on of the inhibitor. The observed corrosion data indicate that the inh ibition of copper corrosion is due to surface adsorption of inhibitor molecules which follow the Langmuir adsorption isotherm. The results o f potentiodynamic measurements indicate that all investigated compound s act mainly cathodically.