Main Article Content
This research focused on the corrosion behavior of gray cast iron and aluminum in alkaline medium (0.5 M NaOH) with and without inhibitor (water hyacinth Eichhornia crassipes extract) of varying concentrations of 5%, 10%, 15%, 20% and 25%. The corrosion rates of the metal samples were investigated using the weight loss and electrochemical methods alongside the formulation of a dispersant using readily available chemicals to develop a colloidal solution of the extract produced by hot water digestion of the water hyacinth plant leaves. The metallography tests of control samples as well as the most and least corroded samples were carried out using Optical Microscope (OM). The results revealed that the aluminum resulted in minimum corrosion rate of 0.000483 mg/mm2/yr with inhibitor efficiency of 98.93% obtained for sample A5 (25% extract from water hyacinth) while for the gray cast iron, a minimum corrosion rate of -4.4E-05 mg/mm2/yr with inhibitor efficiency of 566.6% obtained for sample C3 (15% extract from water hyacinth). The electrochemical result of aluminum showed increase in corrosion potential from -1.494 VAg/AgCl to -1.482 V Ag/AgCl and that of gray cast iron from -0.5436 VAg/AgCl to -0.2839 VAg/AgCl upon increase in inhibitor concentration. Therefore, the use of water hyacinth (Eichhornia crassipes)extract reduced the corrosion or dissolution rate of gray cast iron and aluminum in (NaOH) sodium hydroxide medium.
Ahmed MME. Fundamentals of corrosion mitigations in oil industry. Sudan Eng. Society Journals. 2019;60.
Ashassi-Sorkhabi H, Ghasemi Z, Seifzadeh D. The inhibition effect of some amino acids towards the corrosion of aluminum in 1 M HCl+ 1 M H2SO4 solution. Applied Surface Science. 2015;249:408-418.
Makar J, Desnoyers R, McDonald S. Failure modes and mechanisms in gray cast iron pipe. Underground Infrastructure Research. 2001;1-10.
Buchweishaija J. Phytochemicals as green corrosion inhibitors in various corrosive media: A review. Tanzania Journal of Science. 2009;35.
Raja PB, Sethuraman MG. Natural products as corrosion inhibitor for metals in corrosive media — A review. Materials Letters. 2008;62:113-116.
Abdel-Gaber A, Khamis E, Abo-ElDahab H, Adeel S. Inhibition of aluminium corrosion in alkaline solutions using natural compound. Materials Chemistry and Physics. 2008;109:297-305.
Chauhan KV, Rawal SK. A review paper on Tribological and Mechanical properties of ternary nitride based coatings. Procedia Technology. 214;14:430-437.
Davis GD, Fraunhofer J, Krebs LA, Dacres CM. The use of tobacco extracts as corrosion inhibitors. CORROSION/2001; 2001.
El-Etre A. Inhibition of aluminum corrosion using Opuntia extract. Corrosion Science. 2003;45: 2485-2495.
Oloruntoba DT, Abbas JA, Olusegun SJ. Water hyacinth (Eichhornia crassipes) leaves extract as corrosion Inhibitor for AISI 1030 steel in sea water. Proceedings of 4th West Africa Built Environment Research (WABER). 2012;1131-1140.
Orhorhoro E, Oyiboruona P, Ikpe A. Investigation and evaluation of the corrosion inhibition properties of water hyacinth extract on low carbon steel. International Journal of Emerging Engineering Research and Technology. 2017;5:45-50.
Sukarni S, Widiono AE, Sumarli S, Wulandari R, Nauri IM, Permanasari AA. Thermal decomposition behavior of water hyacinth (Eichhornia crassipes) under an inert atmosphere, in MATEC Web of Conferences. 2018:00010.
Kadhim LF. The corrosion behavior and wear resistance of gray cast iron. Kufa Journal of Engineering. 2018;9:118-132.
Singh A, Singh V, Quraishi M. Aqueous extract of kalmegh (Andrographis paniculata) leaves as green inhibitor for mild steel in hydrochloric acid solution. International Journal of Corrosion; 2010.
Oloruntoba D, Lawal O, Bayode B. Acid-acid function of Eichhornia crassipes roots as inhibitor for mild steel in 0.5 MH 2 SO 4 solution. Protection of Metals and Physical Chemistry of Surfaces. 2017;53:150-158.
Arockiasamy A, Eliezer D, Wang PT, Horstemeyer M, King RL. Electrochemical hydrogenation and corrosion studies of Ti-48Al-2Cr-2Nb alloy in acidic solution. Anti-Corrosion Methods and Materials. 2010;57:280-289.