Mild Steel Corrosion Inhibition in Hydrochloric Acid Using Cocoa Pod Husk-Ficus exasperata: Extract Preparation Optimization and Characterization

Document Type : Research Article


1 Afe Babalola university

2 Department of chemical science, Yaba College of Technology, Yaba, Lagos State

3 Chemical and petroleum engineering, Afe Babalola University.


This research aimed at studying the optimization of cocoa pod-Ficus exasperate (CP-FE) extract preparation as mild steel anticorrosive agent in hydrochloric acid solution using a central composite design as an optimization tool. The maximum inhibition efficiency of 95.42% was obtained at ethanol volume, extraction time, CP-FE mixing ratio, and CP-FE mass of 500 mL, 48 hr, 5, and 100 g respectively. The coefficient of determination value of 0.9674 between experimental and predicted values suggested that the model developed was exact. The optimum predicted point for CP-FE extract preparation by CCD was 62.02 mL, 9.51 hr, 3.42, and 75.68 g for the ethanol volume, extraction time, CP-FE mixing ratio, and CP-FE mass respectively. SEM images revealed an acid attack on the mild steel surface. Adsorption of CP-FE extracts on the mild steel surface prevents acid attack. FT-IR revealed the presence of carboxyl (-COOH) and hydroxyl (-OH) functional groups. EDS revealed high iron composition on mild steel surface in the presence of CP-FE extracts. Loss of Fe2+ into free HCl solution was observed from the AAS result. Conclusively, mixed cocoa pod-Ficus exasperate extracts exhibited effective corrosion inhibitory attributes for mild steel in HCl solution.


Main Subjects

[1] Uhlig H.H., “Corrosion and Corrosion Control”, 2nd ed. New York, John Wiley and Sons Inc (1971).
[2] Popoola L.T., Grema A.S., Latinwo G., Gutti B., Balogun A., Corrosion Problems During Oil and Gas Production and its Mitigation, Int. J. Ind. Chem., 4(1): 35-50 (2013).
[3] El-Etre A.Y., Inhibition of Acid Corrosion of Carbon Steel Using Aqueous Extract of Olive Leaves, Journal of Colloid and Interface Science, 314(2): 578-583 (2007).         
[4] Panossian Z., Almeida N.L.D., Sousa R.M.F.D., Pimenta G.D.S., Marques L.B.S., Corrosion of Carbon Steel Pipes and Tanks by Concentrated Sulfuric Acid: A Review, Corros. Sci., 58: 1-11 (2012).
[6] Akalezi C.O., Oguzie E.E., Ogukwe C.E., Ejele E.A., Rothmannia Longiflora Extract as Corrosion Inhibitor for Mild Steel in Acidic Media, International Journal of Industrial Chemistry, 6(4): 273-284 (2015).
[7] Ivusic F., Lahodny-Sarc O., Curkovic H.O., Alar V., Synergistic Inhibition of Carbon Steel Corrosion in Seawater by Cerium Chloride and Sodium Gluconate, Corros Sci., 98: 88-97 (2015).
[8] Osman M.M., Shalaby M.N., Some Ethoxylated Fatty Acids as Corrosion Inhibitors for Low Carbon Steel in Formation Water, Mater. Chem. Phys., 77(1): 261-269 (2003).
[9] AbdEl-Maksoud S.A., The Effect of Organic Compounds on the Electrochemical Behaviour of Steel in Acidic Media: A Review, International Journal of           Electrochemical Science, 3(5): 528–555 (2008).
[10] Abdel-Gaber A.M., Abd-El-Nabey B.A., Saadawy M., The Role of Acid Anion on the Inhibition of the Acidic Corrosion of Steel by Lupine Extract, Corrosion Science, 51(5): 1038-1042 (2009).
[11] Abdel-Gaber A.M., Abd-El-Nabey B.A., Khamis E., Abd-El-Khalek D.E., A Natural Extract as Scale and Corrosion Inhibitor for Steel Surface in Brine Solution, Desalination, 278(1-3): 337-342 (2011).
[13] Bartos M., Hackerman N., A study of Inhibition Action of Propargyl Alcohol During Anodic Dissolution of Iron in Hydrochloric Acid, J. Electrochem Soc., 139(12): 3428-3433 (1992).
[14] Zhang Q.B., Hua Y.X., Corrosion Inhibition of Mild Steel by Alkylimidazolium Ionic Liquids in Hydrochloric Acid, Electrochim Acta, 54(6): 1881-1887 (2009).
[15] Prabhu R.A., Venkatesha T.V., Shanbhag A.V., Carmine and Fast Green as Corrosion Inhibitors for Mild Steel in Hydrochloric Acid Solution, J Iran Chem Soc, 6(2): 353-363 (2009).
[16] Nnabuk O.E., Ita B.I., Dodo S.N., Elaoyi D.P.I.,  Inhibitive and Adsorption Properties of Ethanol Extract of Hibiscus sabdariffa Calyx for the Corrosion of MiLd Steel in 0.1 M HCl, Green Chem. Lett. Rev., 5(1): 43-53 (2012).
[17] Olasehinde E.F., Olusegun S.J., Adesina A.S., Omogbehin S.A., Momoh-Yahayah H., Inhibitory Action of Nicotiana Tabacum Extracts on the Corrosion of Mild Steel in HCl: Adsorption and Thermodynamics Study, Nature Sci., 11(1): 83-90 (2013).
[18] Mobin M., Rizvi M., Polysaccharide from Plantago as a Greencorrosion Inhibitor for Carbon Steel in 1 M HCl Solution, Carbohydr Polym, 160: 172-83 (2017).
[19] Alibakhshi E., Ramezanzadeh M., Haddadi S.A., Bahlakeh G., Ramezanzadeh B., Mahdavian M., Persian Liquorice Extract as a Highly Efficient Sustainable Corrosion Inhibitor for Mild Steel in Sodium Chloride Solution, J Cleaner Prod, 210: 660-672 (2019).
[20] Singh A., Ansari K.R., Haque J., Dohare P., Lgaz H., Salghi R., Effect of Electron Donating Functional Groups on Corrosion Inhibition of Mild Steel in Hydrochloric Acid: Experimental and Quantum Chemical Study, J Taiwan Inst Chem Eng., 82: 233–51 (2018).
[22] Dagdag O., Berisha A., Safi Z., Hamed O., Jodeh S., Verma C., Ebenso E.E., El Harfi A., DGEBA-Polyaminoamide as Effective Anti-Corrosive Material for 15CDV6 Steel in NaCl medium: Computational and Experimental Studies, J. Appl. Polym. Sci., 137: 48402 (2019).
[23] Ajeigbe S.O., Basar N., Hassan M.A., Aziz M., Optimization of Corrosion Inhibition of Essential Oils of Alpinia Galanga on Mild Steel Using Response Surface Methodology, ARPN Journal of Engineering and Applied Sciences, 12(9): 2763-2771 (2017).
[24] Ali A., Falih S., Yousif N., Rezgar R., Kamal I., Modeling and Optimization of Structural Steel Corrosion Inhibition Using Barely Grass Extract as Green Inhibitor, American Journal of Environmental Engineering, 7(4): 73-81 (2017).
[25] Anadebe V.C., Onukwuli O.D., Omotioma M., Okafor N.A., Optimization and Electrochemical Study on the Control of Mild Steel Corrosion in Hydrochloric Acid Solution with Bitter Kola Leaf Extract As Inhibitor, S. Afr. J. Chem., 71(1): 51–61 (2018).
[26] Olawale O., Ogunsemi B.T., Ogundipe S.J., Abayomi S.T., Uguru-Okorie D., Okunnola A.A., Oni S.O., Kolawole O.D., Ikpotokin I., Optimization of Katemfe Seed Extract as a Corrosion Inhibitor for Mild Steel in 0.5M HCl. International Journal of Civil Engineering and Technology, 9(13): 1394-1402 (2018).
[27] Eddy N.O., Odiongenyi A.O., Corrosion Inhibition and Adsorption Properties of Ethanol Extract of Heinsia Crinata on Mild Steel In H2SO4, Pigment & Resin Technology, 39(5): 288-295 (2010).
[28] Box G.E.P., Hunter J.S., Hunter W.G., “Statistics for Experimenters: An Introduction to Design, Data Analysis, and Model Building”, Wiley, New York (1978).
[29] Bas D., Bayaci I.H., Modeling and Optimization I: Usability of Response Surface Methodology, J. Food. Eng., 78(3): 836–845 (2007).
[30] Onukwuli O.D., Omotioma M., Optimization of the Inhibition Efficiency of Mango Extracts as Corrosion Inhibitor of Mild Steel in 1.0 M H2S04 Using RSM, J. Chem. Tech. Metallurgy, 51(3): 302–314 (2016).
[31] Alaneme K.K., Olusegun S.J., Alo A.W., Corrosion Inhibitory Properties of Elephant Grass (Pennisetum purpureum) Extract: Effect on Mild Steel Corrosion in 1M HCl Solution, Alexandria Engineering Journal, 55(2): 1069-1076 (2016).
[32] Aslam R., Mobin M., Aslam J., Lgaz H., Chung I., Inhibitory Effect Of Sodium Carboxymethylcellulose and Synergistic Biodegradable Gemini Surfactants as Effective Inhibitors for MS Corrosion in 1 M HCl, Journal of Materials Research and Technology, 8(5): 4521-4533 (2019).