Study on the performance of Ajowan seeds extract on the corrosion of steel in acidic solution by effect of temperature

Aisha M. Al-Turkestani

King Abd El-Aziz University, Girls College of Education, Chemistry Department, Jeddah, KSA

Received on May 05, 2010 and accepted on June 07, 2010

ABSTRACT

Electrochemical measurements (EIS and PDP) have been used to study the temperature effect in the range (30p C - 70p C) on the performance of Ajowan seeds extract (ASE) and its inhibitive effects on the corrosion of steel in 2.0M H2SO4. A good agreement between the data obtained by impedance and polarization measurements was found. Results obtained reveal that ASE reduces the corrosion rate at all temperatures studied. The inhibition efficiency increases with rise temperature and the activation corrosion energy decrease in presence of ASE suggest a chemical adsorption model for the corrosion processes.Thermodynamic parameters, Ea, DH#, DS# have been calculated and are discussed.

Keywords : Steel, Acidic inhibition, Temperatur effect, Acidic corrosion.