Benedict Iserom Ita

QSAR, DFT and quantum chemical studies on the inhibition potentials of some carbozones for the corrosion of mild steel in HCl

Experimental aspects of the inhibition of the corrosion of mild steel in HCl solutions by some carbozones were studied using gravimetric, thermometric and gasometric methods, while a theoretical study was carried out using density functional theory, a quantitative structure–activity relation, and quantum chemical principles. The results obtained indicated that the studied carbozones are good adsorption inhibitors for the corrosion of mild steel in HCl. The inhibition efficiencies of the studied carbozones were found to increase with increasing concentration of the respective inhibitor. A strong correlation was found between the average inhibition efficiency and some quantum chemical parameters, and also between the experimental and theoretical inhibition efficiencies (obtained from the quantitative structure–activity relation).

The inhibition of mild steel corrosion in hydrochloric acid by 2,2′-pyridil and α-pyridoin

Abstract The effect of closely related α-pyridoin and 2,2′-pyridil on the corrosion behaviour of mild steel in hydrochloric acid solution has been studied. Weight loss and hydrogen evolution measurements reveal that α-pyridoin gives a better inhibition effect than 2,2′-pyridil. The inhibition effect is more pronounced with increasing temperature as well as inhibitor concentration. Chemical adsorption mechanism has been proposed for the two inhibitors. α-Pyridoin and 2,2′-pyridil obey the Freundlich adsorption isotherm equation at all concentrations and temperatures. The higher efficiencies of the α-pyridoin have been explained in terms of high solubility of the compound facilitated by hydrogen bonding with solvent molecules. α-Pyridoin is also considered to form a more stable bond with mild steel.

Theoretical and experimental studies on the inhibition potentials of aromatic oxaldehydes for the corrosion of mild steel in 0.1 M HCl

Experimental aspect of the inhibition of the corrosion of mild steel by oxaldehydes was carried out using gravimetric, gasometric and thermometric methods while the theoretical studies were carried out using quantum chemical principle and quantitative structure activity relation (QSAR) approaches. The results obtained indicated that the studied oxaldehydes are good inhibitors for the corrosion of mild steel in HCl solutions. The adsorption of the inhibitors on mild steel surface is spontaneous, exothermic and is consistent with the assumptions of Langmuir adsorption isotherm. Excellent correlations were found between the calculated quantum chemical parameters and experimental inhibition efficiencies of the studied compounds. Correlations between theoretical and experimental inhibition efficiencies (for the different Hamiltonians, namely, PM6, PM3, AM1, RM1 and MNDO) were very close to unity. Condensed Fukui function and condensed softness have been used to determine the sites for electrophilic and nucleophilic attacks on each of the inhibitors.

Magnetic properties of lanthanum orthoferrite fine powders prepared by different chemical routes

Fine powders of lanthanum iron oxide, LaFeO3, have been prepared by solid state reaction as well as sol-gel synthesis and nebulized spray pyrolysis. Structures, morphologies and magnetic susceptibility measurements of these powders have been examined. The powders prepared by all the three low-temperature routes contain nearly spherical particles with an average diameter of 40 nm. These samples show a lower Neel temperature than the powder prepared by solid state reaction besides showing much lower magnetic susceptibility at low temperatures.

Inhibitive and adsorption properties of ethanol extract of Hibiscus sabdariffa calyx for the corrosion of mild steel in 0.1 M HCl

Abstract The inhibitive and adsorption properties of ethanol extract of Hibiscus sabdariffa calyx were studied using gravimetric, gasometric, thermometric, and Fourier transform infrared methods of monitoring corrosion. The results obtained indicated that ethanol extract of Hibiscus sabdariffa calyx is a good adsorption inhibitor for the corrosion of mild steel in HCl solutions. The adsorption of the inhibitor on mild steel surface is spontaneous and supports the Langmuir adsorption model. From the calculated values of free energy of adsorption, the activation energy, and the variation of inhibition efficiency with temperature, it can be concluded that the initial mechanism for the adsorption of ethanol extract of Hibiscus sabdariffa calyx on mild steel surface is physical adsorption. Analysis of spectra obtained from the Fourier transform infrared spectrophotometer indicated that there is an interaction between iron in mild steel and the inhibitor.

A study on the inhibition of mild steel corrosion in hydrochloric acid by pyridoxol hydrochloride.

The inhibition of the corrosion of mild steel in 2M hydrochloric acid solutions by Pyridoxol hydrochloride (PXO) has been studied using weight loss and hydrogen evolution techniques. The inhibitor (PXO) exhibited highest inhibition efficiency of 71.93% at the highest inhibitor concentration of 1.0 x 10 -2 M investigated and a temperature of 303K from weight loss result. Also, inhibition was found to increase with increasing concentration of the inhibitor and decreasing temperature. A first order type of mechanism has been deduced from the kinetic treatment of the weight loss results and the process of inhibition attributed to physical adsorption. The results obtained from the two techniques show that pyridoxol hydrochloride could serve as an effective inhibitor of the corrosion of mild steel in HCl acid solution. The compound obeys the Langmuir adsorption isotherm equation.

QSAR and quantum chemical studies on the inhibition potentials of some amino acids for the corrosion of mild steel in H

Experimental studies on the inhibitive and adsorption properties of leucine, alanine and glycine for the corrosion of mild steel in H

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