Corrosion inhibition of carbon steel in hydrochloric acid solution using pomegranate leave extracts

Abstract

The inhibitive action and adsorption behaviour of pomegranate leave extract (PGLE) on corrosion of carbon steel in 1M HCl solution at 293-333 K was investigated through chemical (weight loss measurements), electrochemical (potentiodynamic polarisation) and surface analysis [Fourier transform infrared (FTIR) and X-ray diffraction (XRD)] methods. Results obtained shows that the adsorption of PGLE molecules on the C steel surface obeyed the Langmuir adsorption isotherm and acts as mixed type inhibitor for C steel in 1M HCl with anodic as its dominant inhibitor at high concentration. The inhibitory property of the extract was discussed in terms of the mechanism by which its components adsorb onto the C steel surface. Activation energy of corrosion and other thermodynamic parameters such as standard free energy, standard enthalpy and standard entropy of the adsorption process as well as FTIR and XRD examinations of the electrode surface revealed that the corrosion inhibition of C steel in 1M HCl in the presence of PGLE is mainly controlled by the physical adsorption process.

A study of the gorse aqueous extract as a green corrosion inhibitor for mild steel in HCl aqueous solution

“…The values of E a are greater than the corresponding values of ΔH*, showing that the corrosion process must involve a gaseous reaction, merely the H 2(g) evolution, allied with a decrease in the total reaction volume. Furthermore, the difference between E a and ΔH* is 2.6 kJ mol −1 , which is equal to the average value of RT (2.6 kJ mol −1 ) and indicates that the corrosion process is a unimolecular reaction (13). The activation entropy ΔS* was negative both in the absence and in the presence of the inhibitor, implying that the activated complex represented the rate determining step with respect to the association rather than the dissociation step.…”

“…The activation entropy ΔS* was negative both in the absence and in the presence of the inhibitor, implying that the activated complex represented the rate determining step with respect to the association rather than the dissociation step. This infers that there was a decline in the disorder from the reagents to the activated complex (13).…”

Microstructure, mechanical properties and corrosion performance of a few TMT rebars

“…12 The corroded surface of TMT rebars were characterised by a 'Bruker-Advance D8' XRD machine integrated with a copper tube with an operating voltage and current of 40 kV and 30 mA, respectively. XRD data were collected over a 2θ range of 10-80°with a step of 0.01°s −1 .…”

Corrosion Inhibition of Carbon Steel Using Palm Oil Leaves Extract

“…The carbon steel specimens were cleaned, scrubbed, and polished with sandpapers grade 400 and 600. Then the specimens were degreased with acetone and rinsed with distilled water, dried, stored in desiccators and reweighed [8]. For polarisation measurement, the carbon steel specimens were connected to a copper wire and embedded in epoxy resin.…”

“…As to focus on the need to develop a new type of green inhibitor which is nontoxic and cheap, palm oil is one of the potential natural products which is nontoxic, abundant, and environmentally friendly [5][6][7]. Previously, Abboud et al [8] studied the effect of pomegranate leaves extract on carbon steel in hydrochloric acid using the weight loss method, potentiodynamic polarisation, and surface analysis. Vidhya and Rose [9] also investigated Solanum nigrum leaves as a corrosion inhibitor.…”