American Journal of Applied Sciences

The Effect of Temperature and Acid Concentration on Corrosion of Low Carbon Steel in Hydrochloric Acid Media

Anees A. Khadom, Aprael S. Yaro, Abdul Amir H. Kadum, Ahmed S. AlTaie and Ahmed Y. Musa

DOI : 10.3844/ajassp.2009.1403.1409

American Journal of Applied Sciences

Volume 6, Issue 7

Pages 1403-1409

Abstract

Problem statement: The effect of different temperatures and acid concentrations on the corrosion of low carbon steel in hydrochloric acid were addressed in this study. Approach: The effect of temperature was explained by application of Arrhenius equation and transition state theory, while the acid concentration effect was explained using reaction kinetic equations. The combined effect of temperature and acid concentration then modeled using a nonlinear regression method. Results: A detail of thermodynamic parameters of activation (E, ΔH* and ΔS*) and kinetic studies for the corrosion reaction were obtained. Nonlinear corrosion rates as a function of temperature and acid concentration equation were estimated with a good prediction corrosion rates values. Conclusion: The values of activation energy E and enthalpy of activation ΔH* decrease with increase in acid concentration indicating the increasing in reaction rate. Entropy of activation ΔS* tend to lower values with increasing in acid concentration which indicated that the activated complex was more orderly relative to the initial state. The corrosion reaction was approximately firs order reaction. The observed corrosion rate values from the experimental data were in a good agreement with that predicated by the mathematical equation.

Copyright

© 2009 Anees A. Khadom, Aprael S. Yaro, Abdul Amir H. Kadum, Ahmed S. AlTaie and Ahmed Y. Musa. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.