Investigation of Dracocephalum extract based on bulk and nanometer size as green corrosion inhibitor for mild steel in different corrosive media

Abstract

In recent years, green corrosion inhibitors derived from natural plant resources have garnered much interest. In the present work, at first, we investigated the corrosion behavior of mild steel (st-37) in the presence, and absence of Dracocephalum extract based on bulk size as a corrosion inhibitor in two widely used acidic environments (0.5 M H2SO4, and 1.0 M HCl), at room temperature. Then, we used Dracocephalum extract based on nanometer size to reduce the optimal concentration of inhibitor, increase the corrosion resistant, and efficiency. Dracocephalum extract does not contain heavy metals or other toxic compounds, and also good characteristics such as low cost, eco-friendly, and widespread availability, make it suitable nature candidate as an environmentally safe green inhibitor. The anticorrosive behavior was assessed using electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PP). In all of the studies, the inhibitory efficiency (IE%) increased as the extract dose was increased. But by using nano extract, in addition to maintaining high efficiency, the amount of inhibitor was reduced significantly. The highest IE% is 94% at the best dose of nano extract (75 ppm), but the highest IE% is 89% at the best dose of the bulk extract (200 ppm) in H2SO4 solution. Also, for the HCl solution, the highest IE% is 88% at the best dose of nano extract (100 ppm), but the highest IE% is 90% at the best dose of the bulk extract (400 ppm), by polarization method. The PP results suggest that this compound has an effect on both anodic, and cathodic processes, and that it adsorbs on mild steel surface according to the Langmuir adsorption isotherm. Optical microscopy, scanning electron microscopy (SEM) analysis, and a solid UV–Visible reflection spectrum were used to investigate the alloys' surface morphology.

The Power of Lichens: New Eco‐Friendly Corrosion Inhibitors from Nature

“…Further similar results, concerning the effect of inhibitor concentration on corrosion percentage, were obtained by Heakal et al [37] . and Belakhdar et al., [35] who hypothesized that increasing the concentration of the aqueous extract of Centaurea Cyanus (Cornflower, honey plant) results in more molecules of the inhibitor being adsorbed at the metal/corrosive medium interface, thus covering the same defects and active anodic zones on the metal surface.…”

“…As they are readily available, biodegradable, non-polluting, and renewable. [37] This work is a continuation of our previous research into the antioxidant, antimicrobial, and anti-inflammatory properties of lichen extracts, during which we identified some interesting secondary metabolites. [12,18,19,25,26] This preliminary research demonstrates that these lichen extracts' active components may also have corrosion-inhibiting effects.…”

“…A potential alternative to corrosion inhibitors is natural extracts and their secondary metabolites, which are environmentally friendly and can be less expensive. As they are readily available, biodegradable, non‐polluting, and renewable [37] …”

“…The corrosion process is a natural degradation of metals and alloys that aim to reach a more stable state. [27,36,37] It's a serious problem that requires special attention because of its impact on safety, materials maintenance, and the economics of technological applications. In 2013, corrosion cost the world $2.5 trillion, or 3.4 % of global GDP.…”

Unraveling the corrosion inhibition behavior of prinivil drug on mild steel in 1M HCl corrosive solution: insights from density functional theory, molecular dynamics, and experimental approaches

“…To assess the corrosion inhibition efficiency of Prinivil, electrochemical analysis including EIS and PDP were conducted utilizing the Metrohm Autolab NOVA 2.1.7 electrochemical apparatus. The experiments were performed in a single-chamber electrochemical cell designed for evaluating various flat samples ( Golshani et al, 2023 ; Simović et al, 2023 ). This cell incorporated a three-electrode system: mild steel as a working electrode having a 1 cm 2 accessible area, a Pt rod (99.9% purity) serving as the counter electrode and a reference electrode (saturated calomel electrode (SCE)).…”