THE INFLUENCE OF BENZOYL HYDRAZINE AND SOME OF ITS SUBSTITUENTS ON CORROSION INHIBITION OF CARBON STEEL IN SULPHURIC ACID SOLUTION

Abstract

The influence of synthesised benzoyl hydrazine and some of its substituents on the inhibition of corrosion of carbon steel in 1M sulphuric acid solution were investigated using weight loss, gasometric measurements, potentiodynamic polarisation studies and impedance measurements. Corrosion kinetic parameters clearly revealed the fact that the inhibition of corrosion of carbon steel by these compounds was under mixed control. The effect of temperature on the corrosion behaviour of carbon steel in 1M H2SO4 with optimum concentration of inhibitors was studied in the temperature range 40°‐60°C. The activation energy (Ea) and free energy of adsorption (ΔGads0) were determined for all the inhibitors. The adsorption of these compounds on the carbon steel surface from 1M H2SO4 was observed to obey the Langmuir adsorption isotherm relationship.