Effect of Pyridine and its Derivatives on the Corrosion of 70/30 Brass in 1%H 2 SO 4 Solution

Abstract

The inhibitive action of Pyridine and some of its derivatives (2-,3-, and 4-Picoline) towards the corrosion of 70/30 brass in l% H₂SO₄ solution has been investigated. Weight loss, solution analysis and potentiostatic polarisation studies were carried out in 1% H₂SO₄ with various concentrations of the four inhibitors. All the compounds except 3-Picoline werefound to act as mixed inhibitors and allfour compounds obey the Langmuir adsorption isotherm up to their optimum concentrations. The inhibitive efficiency of these compounds may be arranged in the following order: 2-Picoline > 4-Picoline > 3-Picoline > Pyridine. The influence of the substituent -CH₃ group in the Pyridine ring is explained on the basis of molecular structure.