Investigation of Natural Extracts as Green Corrosion Inhibitors in Steel Using Density Functional Theory

Abstract

Steel is a material that has low resistance to corrosion when interacting with a corrosive environment. The application of natural extracts as green inhibitors is able to provide good performance in inhibiting corrosion of steel with high inhibition efficiency. Natural extracts that are effective and efficient as corrosion inhibitors on steel are those which in their compound structure contain heteroatom groups (such as O, N, S, P) and aromatic rings. This work provides an important comparative overview for the development of green inhibitor natural extracts in steel. The results of theoretical studies based on quantum mechanics with the DFT method at the atomic level based on molecular orbitals, chemical quantum parameters, and adsorption characteristics show results that are in accordance with experimental studies. The frontier molecular orbital (FMO) plot shows the distribution of electron density in the HOMO-LUMO region as a predictor of the active site of the inhibitor molecule interacting with the steel surface. Quantum chemical parameters such as ionization potential (I), electron affinity (A), absolute electronegativity (χ), hardness (η), softness (σ), fraction of electrons transferred (ΔN), electrophilicity (ɷ), and electron backdonation (ΔEback-donation) was calculated to obtain a correlation between the electronic properties of the inhibitor molecule and the corrosion inhibition potential. The results of the calculation of the quantum chemical parameters show the reactivity of the inhibitor molecule which has a very good potential to interactand bind strongly to the steel surface. This has the potential to make the inhibitor molecule have a high inhibition efficiency. Chemical adsorption and/or physical adsorption by forming complex compounds between inhibitor molecules and the steel surface are corrosion inhibition mechanisms to protect steel from a corrosive environment.The development of future studies should be able to display the mechanism of interaction and inhibition of inhibitor molecules in more detail and systematically at the atomic level on several metal surfaces such as Fe, Al, Cu, and others.

Artificial Intelligence Berbasis QSPR Dalam Kajian Inhibitor Korosi

“…Investigasi inhibitor korosi berbasis ekstrak bahan alam (green inhibitor) terus berkembang karena bersifat ramah lingkungan, renewable, biodigradable, tidak menimbulkan polutan, tidak beracun, mudah diproduksi, murah, dan memiliki efisiensi anti korosi yang tinggi [28], [29]. Green inhibitor yang dalam struktur senyawanya mengandung cincin aromatik dan gugus heteroatom (seperti O, N, S, P) dianggap sebagai inhibitor yang efekif dan [30]- [32].…”

EFEKTIVITAS EKSTRAK METANOL DAUN NANGKA (Artocarpus heterophyllus Lam.) SEBAGAI INHIBITOR ALAMI TERHADAP KOROSI PADA BAJA ST 37 DALAM MEDIA KOROSIF HCl

“…Inhibitor organik adalah jenis inhibitor yang aman karena memiliki sifat yang biodegradable, ramah lingkungan serta dapat menggunakan bahan dasar yang terdapat di alam. Ekstrak bahan alam umumnya mengandung senyawa organik seperti polifenol, alkaloid, flavonoid, karbohidrat, asam amino, protein dan senyawa yang memiliki pasangan elektron bebas pada sistem rantai aromatiknya yang dapat berikatan dengan muatan positif pada logam sehingga terjadi proses adsorpsi antara permukaan logam dengan senyawa inhibitor (Rachmawati, 2017 ;Akrom et al, 2022).…”

“…Dapat dilihat pada Gambar 6 yaitu lapisan korosi baja ST 37 dalam HCl 1 M dan Gambar 7 yang merupakan ilustrasi mekanisme interaksi senyawa inhibitor terhadap permukaan baja yang dapat melalui reaksi kimiawi dan reaksi fisika untuk membentuk senyawa kompleks antara inhibitor dengan permukaan logam (Akrom, 2022).…”

“…Secara Kimia dan Fisika Ketika ion Fe 2+ terdifusi ke dalam larutan elektrolit, maka inhibitor yang mengandung atom oksigen akan mendonorkan sepasang elektron pada permukaan logam. Senyawa kompleks inilah yang akan melekat pada permukaan baja yang akan menghalangi terjadinya proses korosi lebih lanjut karena senyawa kompleks tersebut akan terserap pada permukaan baja dan melindungi permukaan baja (Ali et al, 2014 ;Akrom et al, 2022).…”

A Machine Learning Model for Evaluation of the Corrosion Inhibition Capacity of Quinoxaline Compounds

“…Inhibitor technology is a straightforward, practical, and economical way to control corrosion [1], [2]. One well-known and efficient method of preventing corrosion damage is to use inhibitors [3], [4].…”