Performance of Mild Steel in Nitric Acid/<i>Carica Papaya</i> Leaf Extracts Corrosion System


  • Makanjuola Oki Landmark University
  • Paul A. L. Anawe
  • John Fasakin


Carica papaya, corrosion inhibitor, weight loss, gasometry


Corrosion inhibition efficiency of leaf extracts from Carica papaya has being investigated using gravimetric, gasometric and thermometric techniques. Carica papaya leaf extracts reduced the corrosion rate of mild steel in 2.5M nitric acid by interfering with both anodic and cathodic reactions. The corrosion rate in the absence of the inhibitor was 840 mmpy while at 60% inhibitor concentration, it was 60 mmpy. The corrosion rate decreased rapidly initially as the concentration of the inhibitor increased and attained an efficiency of 93% at a concentration of 60%. The complimentary inhibition efficiencies, E%, obtained from thermometric and gasometric techniques are similar in values and range from about 93% to 96%. The adsorption of the active components of the leaf extracts follows the Langmuir adsorption isotherm

Author Biography

Makanjuola Oki, Landmark University

Currently, MAKANJUOLA OKI is an Associate Professor with a prima facie case for professor at Landmark University in the Department of Mechanical Engineering.


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How to Cite

Oki, M., Anawe, P. A. L., & Fasakin, J. (2015). Performance of Mild Steel in Nitric Acid/<i>Carica Papaya</i> Leaf Extracts Corrosion System. Asian Journal of Applied Sciences, 3(1). Retrieved from