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This paper aims to evaluate the inhibitive potential of borage flowers’ aqueous extract (BFAE), Borago officinalis L., against the corrosion of mild steel in 1.0 M phosphoric acid.

Evaluation was carried out by chemical hydrogen evolution (HE), mass loss (ML) and electrochemical potentiodynamic polarization (PDP) measurements. SEM-EDX analysis also was used to confirm the existence of the adsorbed film.

It was found that the inhibition efficiency of BFAE increases with the increase in its concentration, but decreases with the increase in temperature. The potentiodynamic polarization curves indicated that BFAE acts as a mixed-type inhibitor with a predominantly anodic action. The adsorption of BFAE on mild steel surface was found to obey Langmuir and thermodynamic-kinetic adsorption isotherms by forming a thin film on the metal surface. SEM-EDX analysis confirms the corrosion inhibition ability of BFEA in 1.0 M H₃PO₄ by forming a thin film on mild steel surface. In this study, the inhibitive action of BFAE components is discussed on the basis of the physical adsorption mechanism. The same results were obtained for both the freshly prepared extract and the one that kept in a refrigerator for one year.

This paper indicates that BFAE can act as a good inhibitor for the corrosion of mild steel in 1.0 M H₃PO₄ even after one year of preparation.

The purpose of this paper is to investigate the mechanisms of low alloyed medium-carbon steel (LAMCS) corrosion in 0.5 M H₂SO₄ inhibited by seeds oils of rubber (SOR), Neem (SON) and Jatropha (SOJ) containing varying degree of free fatty acid (FFA).

Specific gravity, acid values and FFA compositions of oils were determined. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and X-ray diffraction (XRD) are techniques used to investigate the corrosion inhibition mechanisms with evaluated Gibbs free energy of adsorption.

Corrosion inhibition efficiencies of oils reached values >99% as obtained from PDP and EIS. Protective oxide layer was formed on LAMCS consequent on containment of carbonyl and hydroxyl groups in the FFA of SOR, SON and SOJ, respectively. The SOR and SOJ are found to be mixed inhibitors, whereas SON behaved as anodic inhibitor. Mechanism of adsorption of SOR was synergistic between physisorption and chemisorption, while SON and SOJ exhibited physisorption. SEM micrographs images showed that uninhibited sample exhibited thicker mass of corrosion products. Formation of protective oxide layer was confirmed by XRD diffractograms.

This study has shown that the need for modification of vegetable seed oils containing FFA is unnecessary as the hydroxyl and carbonyl groups of the FFA contained in the respective oil were found to be the center of adsorption of the oils on the steel surface. Hence, cost and by-products associated with modification of oils used as corrosion inhibitors are eliminated.

SOR, which has the highest percentage FFA, was found to be the most influential on the corrosion inhibition mechanism of LAMCS, specifically within 0.01–0.02 g/mL concentration. FFA contained in the respective seed oil aided formation of protective oxide layer at interface between H₂SO₄ and LAMCS, relative to amount composed.

Surface pretreatment of iron and its alloys to remove stains and inorganic contaminants on the metal surface undergoes dissolution by virtue of the strong acidic media thereby increasing its susceptibility to corrosion. The purpose of this study is to explore the corrosion mitigation prospects of green corrosion inhibitors on mild steel surface.

Corrosion inhibition performance of Garcinia gummi-gutta leaf extract (GGLE) was explored against mild steel in 1 M HCl solution using the weight-loss method, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques. Surface characterization was carried out to study the mechanism of inhibitor action.

The concentration of GGLE varied from 100 to 6,000 ppm and the result indicates that corrosion inhibition efficiency was amplified by raising the inhibitor concentration. The maximum inhibition efficiency was 82.2% at 6,000 ppm concentration. EIS results show the development of a protective layer of inhibitor molecule over the metal surface and PDP demonstrates that the inhibitor operates as a mixed-type inhibitor. Scanning electron microscopy and atomic force microscopy were executed to assess the surface morphology and roughness, respectively.

To the best of the authors’ knowledge, so far, no studies have been reported on the corrosion inhibition performance of GGLE which is rich in many bioactive components especially hydroxyl citric acid. This work encompasses the corrosion inhibition capability of GGLE against mild steel in an acidic medium.

This paper aims to investigate influence of extraction solvent on the efficacy of apricot pomace extract (APE) as a sustainable corrosion inhibitor for mild steel in sodium chloride solution.

The chemical profiles of the extracts were analyzed using gas chromatography–mass spectrometry. Total phenolic, total flavonoid content and antioxidant properties of the extracts were determined. Besides, gravimetric, potentiodynamic polarization and atomic force microscopy were used to study the corrosion inhibition. The effect of immersion period on inhibition efficiency was evaluated. The reaction mechanism of the inhibitor was also discussed.

Corrosion inhibition decreasing is in the following order: solution of 2-propanol/ethanol apricot pomace (E/PAPE) extract > ethanol (EAPE) > 2-propanol (PAPE). The gravimetric, polarization measurements and surface analysis revealed that the growth of inhibitory properties is prolonged, and corrosion rate reduction after 40–48 h of exposure was studied.

APEs play an important role in the corrosion inhibition of mild steel in sodium chloride solution. Moreover, its application is potentially possible in industries.

The results contribute to the integrated valorization of food waste.

The different compositions of the conversion/oxidation products of organic substances in solution were studied. The formation of polymerized flavanol-aldehyde adducts and oxidized quinone compounds or tautomers structures because of extract transformation in water causes main corrosion reduction in 40–48 h.

The study aims to find new anticorrosive components from a plant source, namely, Pachysandra terminalis Sieb. et Zucc. (P. terminalis), a traditional medicinal shrub predominantly used by Tujia people.

Because phenolic components from plants are known for its numerous values in several fields, the corrosion inhibitive ability of P. terminalis extract was analyzed by electrochemical studies (polarization, electrochemical impedance spectroscopy) and surface examination (by scanning electron microscopy [SEM], energy-dispersive X-ray spectroscopy [EDX] and atomic force microscopy [AFM]).

The examination of total phenolic content (TPC), total flavonoids content (TFC) and individual phenols (UHPLC) showed the presence of 85.21 mg/g (TPC), 25.38 mg/g (TFC), protocatechuic acid (62.10 µg/g), gentisic acid (60.21µg/g), rutin (50.12 µg/g), kaempferol (46.58 µg/g) and p-Coumaric acid (42.35µg/g) . The polarization study shows that the maximum shift is (16 mV), imposing a mixed mode of inhibition, dominantly anodic. The surface morphology studies by SEM, EDX and AFM confirmed the adsorption of phytochemical components on the low carbon steel surface blocking the active sites.

The study unveils the inhibitive nature of P. terminalis, preventing aggressive attack by 0.5 M HCl on low carbon steel. This also exhibits few phenols present in methanolic leaf extract which may be the role player of corrosion inhibition.

Famed for many centuries as perhaps the best thirst‐quencher of all fruits, the lemon has a long history but one which nevertheless does not extend back to Ancient Greek and Roman times. The true origin of the lemon is uncertain, but it may well have been a natural hybrid of the citron and the lime, from which it differs in both shape and thinness of rind. It reached Europe by way of the North African countries and Spain between the ninth and eleventh centuries.

I felt myself the recipient of a great honour when asked to read a paper on this subject before your Society. One difficulty, however, at once confronted me, and that was that what your society might regard as an act of sophistication of food, I might believe to be only a perfectly legitimate manufacturing improvement. I had no wish to masquerade before you as a wolf in sheep's clothing, and therefore stated my position to your secretary. As a result of some correspondence, I think that he, as your representative, and I, both felt that granted such differences of opinion, they themselves constituted one of the strongest arguments in favour of the formation of a Court of Reference. There are, no doubt, many processes which are considered by their inventors and users as of advantage in the manufacture of food, whereas others regard them with the greatest distrust and aversion. In most cases I believe the members of both these classes to be high‐minded and honourable men. That being so, it is submitted that the best method of arriving at the real facts is the establishment of an impartial, broad‐minded, and capable Court of Reference, to which such matters should be submitted for examination and decision.