Understanding the inhibitory mechanism and protection performance of avocado seed nanoparticle extract in API X65 steel corrosion in a 1M HCl acid environment

Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, Pretoria, South Africa

^* Corresponding author: sweetdamsel08@gmail.com

Abstract

There is currently a high need for effective and nontoxic corrosion inhibitors in the acidising industrial process due to rising concern for human life and environmental sustainability. As a result, in this work the anticorrosive efficiency of avocado seed nanoparticle extract (ASN) in APIX65 pipeline steel corrosion was examined in 1M HCl medium through weight loss and the potentiodynamic polarisation approach. The inhibitor morphology, particle size, and elemental composition were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The SEM examination of the steel surface indicates a considerable difference, demonstrating that the inhibitor formed a protective barrier on the metal surface with heteroatom constituents from the inhibitor. The findings show a corresponding increase in inhibition efficiency as the inhibitor concentration increases, with the highest inhibitor efficiency found at 95.65% for 5 g of ASN in 1 M HCl solution. Regarding the electrochemical test, ASN performs as a mixed-type corrosion inhibitor. The weight loss test findings corroborated the electrochemical investigations, indicating that ASN had a high inhibitive effect on X65 steel in an acid medium. The ASN nanosize gives a huge surface area, resulting in increased reaction activity and the development of more shielding coatings. This study sheds light on the development of sustainable corrosion inhibitors for X65 steel.