Insight into the anti-corrosive performance of Persea Americana seed extract as a high-efficiency and sustainable corrosion inhibitor for API 5 L X65 pipeline steel in 1 M HCl solution

Presently, there is high demand for less toxic and effective corrosion inhibitors for the acidizing process owing to the toxicity of the existing inhibitors. Therefore, the objective of this study is to explore the feasibility of Persea Americana seed extracts (PASE) as sustainable corrosion inhibitors to mitigate the corrosive effect of 1 M HCl on API 5 L X65 pipeline steel using weight loss, and potentiodynamic polarization techniques. Fourier transform infrared spectroscopy (FTIR) was utilized to establish the inhibitor's functional group. The result obtained shows that the inhibition efficiency increased with concentration, with the best inhibitor efficiency obtained as 95.65% for 5 g PASE in 1 M HCl solution. The electrochemical tests revealed that PASE behaves as a mixed-type corrosion inhibitor. The adsorption of PASE followed the Langmuir adsorption isotherm. Results from FTIR confirm that PASE extracts contain hydroxyl group compound, flavonoid, and phenolic content which can be utilized as corrosion inhibitors. The SEM analysis shows a notable difference in the steel surface with inhibitor owing to the protective barrier formed on the metal surface. In the formulation of acidizing corrosion inhibitors, PASE is a promising active compound. The data obtained from the weight loss test is in agreement with the electrochemical tests and demonstrates excellent inhibitive behavior of PASE on X65 steel in the acid solutions. This research provides insight into the development of sustainable corrosion inhibitors for X65 steel.