Mangifera Indica leaves crude ethanolic extract as a corrosion inhibitor for mild steel in acidic and basic media

Abstract

Mild steel corrosion adversely impacts various industries, specially in acidic environments, leading to reduced metal efficiency. This study explored the efficacy of mango leaves crude ethanolic extract (MLCEE) as a natural corrosion inhibitor for mild steel. Different concentrations, such as treatment 1 (25%), treatment 2 (50%), treatment 3 (75%), and treatment 4 (100%) MLCEE, were tested, along with a commercial inhibitor (WD-40). The dilution method was utilized to obtain the concentrations and acid/base solutions. The mild steel plate was cut and pre-treated through rapid thermal annealing. The mild steel was then immersed in 1M HCl and 1M NaOH for its corrosion test. Gravimetric weight loss was computed and statistically analyzed using one-way ANOVA and Tukey's HSD Test to determine the treatments’ effectiveness, revealing that the 100% concentration significantly differed from other treatments in both mediums, where it had a p-value of 0.00. Treatment 4 yielded no significant change in the weight of mild steel before (5.05 g) and after (5.01 g) immersion in HCl, and in weight before (4.65 g) and after (4.61 g) immersion in NaOH, as shown in the paired sample ttest, thus it indicates its potential as a metal coating against corrosion activity. This implied that MLCEE is capable of inhibiting corrosion inhibition and can withstand aggressive media. These results may become a basis for future studies covering metal corrosion and plant extract utilization. However, different annealing processes may be considered to promote better adsorption, and other parameters may be added to further explore the efficacy of MLCEE as a potential corrosion inhibitor.

Keywords

• corrosion
• mango leaves
• natural inhibitor
• sodium hydroxide
• hydrochloric acid
• sustainability
• corrosion rate
• inhibition efficiency