Utilization of Extract from Bushcane (Costus Afer) as Green Corrosion Inhibitor for Mild Steel

Abstract

Corrosion has adverse environmental consequences since it affects the manufacturing sector resulting in enormous economic loss. The corrosion characteristics and mechanism of mild in the solution of hydrochloric acid was studied. Extract of bush cane (Costus afer) was screened for physicochemical and phytochemical properties and utilized as corrosion inhibitor for mild steel, the process was optimized using Response Surface Methodology (RSM). The presence of OH, NH of alcohols, phenols, or substituents connected to aromatic rings, C=O for amides and ketones, C-N of aliphatic amines, and C=C of alkenes and nitriles were shown using Fourier Transform Infrared Spectroscopy (FTIR). The optimum condition was found by minimizing time, temperature, inhibitor concentration and corrosion rate while maximizing weight loss, and inhibitor efficiency. The results obtained revealed that the bush cane extract contain saponin, flavonoid, alkaloid and tannin, which suggests the potency of the extract as a good inhibitor as it contains a considerable amount of phytochemical with basic heteroatom. The statistical significance of the weight loss, corrosion rate and inhibitor efficiency were evaluated using the analysis of variance (ANOVA). it was observed that the regression was statistically significant at the F-value of 94.60, 25.87 and 4.72 respectively. P-value of > 0.0235, > 0.0001 and 0.0265 respectively. The optimum temperature, inhibitor concentration and contact time were found to be 27.9°C, 20.0% and 5 hours respectively at desirability value of 0.637. At this optimum condition, the weight loss was found to be 0.102%, corrosion rate was 1.583mg/cm<sup>2</sup>hr and inhibitor efficiency was 62.9%. From the results obtained in this experiment, It is concluded that the bushcane extract can be used as a corrosion inhibitor for the protection of mild steel.