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In the present study, the inhibition performance of mild steel by cherimoya seeds extract was investigated using weight loss measurements, electrochemical techniques, and scanning electron microscope (SEM) coupled with energy���dispersive X���ray spectroscopy (EDX). The experimental data suggested that the cherimoya seeds exhibited a high inhibition performance, which increases with increasing their concentrations. Cherimoya seeds extract present maximum inhibition efficiency of 94% at an optimal concentration of 1g/L. The principal observations that resulted from electrochemical studies are that cherimoya seeds affected both anodic and cathodic reactions (mixed inhibitors). Their adsorption, which is a combination of chemisorption and physisorption, obeyed the Langmuir isotherm model. Furthermore, the temperature effect was carried out at various temperatures ranging from 303 to 328 K to verify the corrosion inhibition performance of cherimoya seeds at higher temperatures. Moreover, SEM���EDX analysis confirmed that cherimoya seeds can ensure remarkable prevention against corrosion through the adsorption onto the metal surface., Moroccan Journal of Chemistry, Vol. 9, No 3 (2021): in progress

L-Cysteine (L-Cyst) was tested as corrosion inhibitor of tin in Na2CO3 0.1M + NaCl 1M solution. The inhibition action of this inhibitor was studied by using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques. Temperature effect on the inhibition efficiency was studied in the range from 298 to 328 K and the values of activation thermodynamic parameters were calculated and explained. Experiment results show that inhibition efficiency increases with increasing of L-Cysteine concentration and decreases slightly with elevation of temperature. L-Cyst is a good inhibitor and inhibition efficiency reach 88% at 10−3M. Analysis of the polarization curves revealed that L-Cyst is considered as a mixed inhibitor. The results from electrochemical measurements and theoretical calculations are in good agreement. The surface morphology of the metal surface was investigated by scanning electron microscopy (SEM)., Applied Journal of Environmental Engineering Science, Vol 7, No 1 (2021)

In this work, we investigate the corrosion behavior of steel rebar (SR) in four simulated concrete pore solutions (CPS): NaOH+KOH (CPS1), Na2CO3 (CPS2), NaOH (CPS3) and Ca(OH)2 (CPS4) medium. Effect of addition of Cl- anions as pollutant on pitting and uniform corrosion of SR is investigated by using potentiodynamic polarization (PDP) technic. The result obtained show that uniform and pitting corrosion of SR are strongly influenced by the nature of simulated CPS. In unpolluted CPS’s, only uniform corrosion of SR is observed in all cases. SR has excellent corrosion resistance in CPS4 compared to the other simulated CPS. In the polluted CPS’s by Cl- anions, we observe an accelerated uniform corrosion especially in CPS1, CPS3 and CPS4 mediums. The sensitivity to localized corrosion of SR varies from one simulated environment to another. It has the best resistance to pitting corrosion in polluted CPS3 medium. In CPS1 (pH = 13) and CPS2 (pH = 11.6) polluted by 3% NaCl, the tendency to pitting corrosion is the same. The localized attack is more pronounced in polluted CPS4 (pH=12.7). These results demonstrate that there are no limit values of the pH and the content of Cl- ions for the initiation of pitting and / or uniform corrosion. Therefore, it is the chemical composition of the simulated medium which imposes the pH value and the Cl- content for systematic corrosion study of the SR in the simulated CPS., Moroccan Journal of Chemistry, Vol 8, No 3 (2020)

The corrosion performance of carbon steel in acidic medium with different concentration of synthesized organic compounds namely: 2-Phenylpyrimido[1,2-a] benzimidazol-4(1H)-one (PPBI), was investigated by Potentiodynamic Polarization Curves (PPC) and Electrochemical Impedance Spectroscopy (EIS) measurements. The obtained results reveal that (PPBI) performs excellently as good corrosion inhibitor for carbon steel in 1.0 M HCl. Polarization curves studies indicated that (PPBI) behaves as mixed-type inhibitor. The calculated inhibition efficiencies from two experiments measurements show the same evolution. Also, the inhibition efficiency was found to increase with increase of the inhibitor concentrations to reach 86 % at 10-3 M of (PPBI) due to the adsorption of the inhibitor molecule on the electrode surface. Impedance measurements spectra exhibit one capacitive and valid the inhibitive ability confirming that this inhibitor inhibits the corrosion in 1 M HCl through adsorption process following Langmuir adsorption isotherm., Applied Journal of Environmental Engineering Science, Vol 6, No 1 (2020)

The inhibition effect of L-methionine (L-Met) on the corrosion of tin in carbonate medium in presence of chloride ions has been studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization technics. Temperature effect on the corrosion behavior with the addition of L-Met studied in the range of temperature from 298 to 328 K. The inhibition efficiency decreases slightly with the increase in the temperature. Results show that L-Met is a good inhibitor and inhibition efficiency reach 82% at 10−3M. The adsorption of this compound on aluminum surface obeys Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters were determined and discussed. SEM analysis revealed that the addition of inhibitor retards the corrosion processes, where the grain boundary attacks were completely hindered by the adsorbed inhibitor molecules, Applied Journal of Environmental Engineering Science, Vol 4, No 3 (2018)

The main objective of this work was to study the inhibition of the corrosion of the Carbon steel, in hydrochloric acid solution medium (1 M), using Lavandula stoechas essential oil .The effect of oil of Lavandula stoechas as an eco-friendly inhibitor for carbon steel corrosion have been investigated in 1 M hydrochloric acid solution by polarization curves, electrochemical impedance spectroscopy (EIS) and gravimetric techniques. Lavandula stoechas oil efficiently inhibited the carbon steel corrosion. The highest value of inhibition efficiency is 83.5% obtained by potentiodynamic polarization and 84.35% by electrochemical impedance spectroscopy measurement at maximum concentration tested. The inhibition efficiency augmented with increase in anise oil concentration but reduced with growth in temperature. Polarization curves show that the tested oil may be considered as mixed type inhibitor and the inhibitor absorption on the carbon steel electrode obeys the Langmuir isotherm. The EIS results indicate that the changes in impedance parameters are related to the adsorption of Lavandula stoechas on the alloy surface., Applied Journal of Environmental Engineering Science, Vol 3, No 4 (2017)

The effect of L-methionine (L-Met) on the passivation and corrosion inhibition of aluminum alloy was investigated in carbonate medium in presence of chloride ions. This inhibitive action against the corrosion of aluminum in corrosive solution was investigated at 298 K using potentiodynamic polarization curves (PDP), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results obtained from the polarization curves reveal that the aluminum in alkaline medium exhibits a phenomenon of passivation with breakdown of passivity. Temperature effect on the corrosion behavior with the addition of (L-Met) studied in the range of temperature from 298 to 328 K. The inhibition efficiency decreases slightly with the increase in the temperature. Results show that L-Met is a good inhibitor and inhibition efficiency reach 87,23% at 10−3M. The electrochemical results are confirmed by scanning electron microscopy (SEM). The adsorption of this compound on aluminum surface obeys Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters were determined and discussed., Moroccan Journal of Chemistry, Vol 6, No 2 (2018)

The influence of 2-pyridyl-benzimidazole (PB) on the corrosion of steel in 1M HCl solution has been studied by weight loss measurements, potentiodynamic polarization (EI) and impedance spectroscopy (EIS) methods. The inhibiting action increases with the concentration of (PB) compound to attain 95.63% at 10-3 M. Polarisation measurements also show that the 2-pyridyl-benzimidazole (PB) acts essentially as a mixte type inhibitor. The cathodic curves indicate that the reduction of proton at the steel surface happens with an activating mechanism. (PB) adsorbs on the steel surface according to Langmuir adsorption model. Effect of temperature is also made in the 298–328 K range. Activation parameters are determined and discussed., Applied Journal of Environmental Engineering Science, Vol 3, No 3 (2017)

The inhibition potentials of methanol extracts of leaves (GFL) and rind (GFR) of Grapefruit plant was investigated by evaluating the corrosion behaviour of carbon steel metal immersed in 1.0 M HCl solution containing various concentrations of the extracts. Electrochemical technical, Gravimetric measurements and adsorption characterization were utilized to evaluate the corrosion inhibition and adsorption properties of the extracts. The results revealed that the studied extracts were efficient inhibitors of corrosion in carbon steel immersed in 1.0 M HCl and that the inhibition efficiency depends on the concentration of the extracts. The activation energies and the negative free energy of adsorption obtained from the adsorption of methanol extracts of leaves and rind of Grapefruit indicate that the methanol extracts were physically adsorbed on the surface of the carbon steel and that the adsorption is endothermic, spontaneous, strong and fit excellently with the assumptions of the Langmuir adsorption isotherm. The activation parameters are determined and discussed., Moroccan Journal of Chemistry, Vol 5, No 3 (2017)

The corrosion behavior of C38 steel in HCl solution with different concentration of newly synthesized Picolinium-based Ionic liquids, 1-2-(4-Nitro Phenyl) 2-oxoethyl) -4N-Nmethyl) Picolinium Bromide (NPOMPB), was investigated by weight loss and electrochemical measurements. The effect of temperature on the corrosion behavior with the addition of (NPOMPB), was studied in the temperature range 298–328 K. Results obtained reveal that (NPOMPB) performs excellently as good corrosion inhibitor for C38 steel in 1.0 M HCl. Potentiodynamic polarization studies have shown that (NPOMPB) inhibition efficiency was found to increase with increase of the inhibitor concentrations to reach 96.5 % at 10-3M of (NPOMPB), due to the adsorption of the inhibitor molecules on the metal surface and the adsorption follows Langmuir’s adsorption isotherm. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. To elaborate the mechanism of corrosion inhibition, the kinetic and thermodynamic parameters for Carbon steel corrosion and inhibitor adsorption, respectively were determined and discussed. The Optical microscopy (OM) was used for its morphological studies. Of the surface film was applied in order to get better understanding about the relationship between the inhibition efficiency and molecular structure and also to show the presence of the interfacial elements., Applied Journal of Environmental Engineering Science, Vol 3, No 2 (2017)

The Kaempferol (KFR), is investigated as a corrosion inhibitor for C38 steel in HCl solution using impedance spectroscopy, polarization curves measurement and weight loss studies. Results obtained reveal that the Kaempferol performs excellently as a corrosion inhibitor for C38 steel in 1.0 M HCl and indicate that the inhibition efficiency increases with the concentration of the inhibitor to reach 96.0 % at 2.10-3 M of the Kaempferol. The effect of temperature on the corrosion behavior of carbon steel in 1 M HCl was also studied. Polarization curves showed that the Kaempferol behaves as a mixed-type inhibitor. The adsorption of the inhibitor on the carbon steel surface obeyed the Langmuir adsorption isotherm. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. Data obtained from EIS technique, were analyzed to model the corrosion inhibition process through appropriate equivalent circuit model; a constant phase element (CPE) has been used. The activation energy as well as other thermodynamic parameters for the inhibition process was calculated and discussed., Applied Journal of Environmental Engineering Science, Vol 2, No 2 (2016)

In this work we studied the inhibition effect of two inhibitors 2-Nitrobenzaldehyde (NBA) and 4-Nitrophenol (PN) on the corrosion of carbon steel (CS) in 0.5 M H2SO4 by weight loss measurement, potentiodynamic polarization methods and electrochemical impedance spectroscopy (EIS) techniques. The results showed that the two inhibitors were a good inhibitors in 0.5 M H2SO4, and their adsorption on the carbon steel surface follows the Langmuir isotherm model in acidic media. The results obtained from the different corrosion evaluation techniques are in good agreement. Polarization curves showed that the inhibitors acted as mixed-type inhibitors in sulfuric acid. Changes in impedance parameters (charge transfer resistance Rct, and double-layer capacitance, Cdl) were indicative of adsorption of the inhibitors on the metal surface, leading to the formation of a protective film. The inhibition efficiency increases with inhibitors concentration to attain the maximum value of 93.46% for NBA and 85.91% for PN at 10−3M. The effect of the temperature on the corrosion behavior with addition of 10-3M of the inhibitors was studied in the range 298-328 K, and some thermodynamic functions of dissolution processes were also determined and discussed. The electronic properties such as the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energy levels, energy gap (LUMO-HOMO), dipole moment and molecular orbital densities were computed., Applied Journal of Environmental Engineering Science, Vol 2, No 2 (2016)

The corrosion behavior of C38 steel in Hcl solution with different concentration of 3,3'-Dimethylbiphenyl-4,4'-diamin (O.Tolidine)(OT) ,was investigated by weight loss and electrochemical measurements. The effect of temperature on the corrosion behavior with the addition of (OT) was studied in the temperature range 298–328 K. Results obtained reveal that (OT) performs excellently as good corrosion inhibitor for C38 steel in 1.0 M Hcl. Potentiodynamic polarization studies have shown that (OT) behaves as mixed-type inhibitors. The inhibition efficiencies, calculated from weight loss measurements, show the same trend as those obtained from electrochemical studies. Also, the inhibition efficiency was found to increase with increase of the inhibitor concentrations to reach 87.84 % at 10-3M of (OT) due to the adsorption of the inhibitor molecules on the metal surface and the adsorption follows Langmuir’s adsorption isotherm. EIS spectra exhibit one capacitive loop and confirm the inhibitive ability. To elaborate the mechanism of corrosion inhibition, the kinetic and thermodynamic parameters for Carbon steel corrosion and inhibitor adsorption, respectively were determined and discussed. Double layer capacitance and charge transfer resistance values were derived from Nyquist plots obtained from impedance studies., Applied Journal of Environmental Engineering Science, Vol 1, No 1 (2015)

Argan Oil (AO) was tested as inhibitor for copper corrosion in 2 M H3PO4 and NaCl 0.3 M. The techniques used in this work were weight loss measurements, potentiodynamic polarisation and Electrochemical Impedance Spectroscopy (EIS). The inhibition efficiency was found to increase with inhibitor content to attain 94% for AO at 7g/L. Inhibition efficiency E (%) obtained from the various methods is in good agreement. The temperature effect on the corrosion behaviour of copper in (2 M H3PO4+ 0.3 M NaCl) was studied by potentiodynamic technique in the range from 298 to 323 K., Moroccan Journal of Chemistry, Vol 2, No 1 (2014)

The inhibition effect of ylang-ylang oil (YYO) and their adsorption on carbon steel surface in hydrochloric acid was realized at temperatures varying between 308 and 338 K by weight loss, EIS, and potentiodynamic polarization techniques. The tested compound showed inhibition efficiency that is superior 87 % for a concentration equal to 1.0 g/L. Polarization measurements indicate that the examined oil act as a mixed inhibitor with predominant anodic effectiveness and the protection efficiency increases with inhibitor concentration but this effect decreased with increasing of temperature. Data obtained from EIS studies were analyzed to model inhibition process through appropriate equivalent circuit models. The adsorption of YYO on carbon steel surface obeys Langmuir adsorption isotherm in acid medium and the activation were determined and discussed., Moroccan Journal of Chemistry, Vol. 4, No 1 (2016)

Carbon steel is widely used in various fields such as the field of agri-food their use in tins and materials used in the food producing seen this material and susceptible to corrosion phenomena are in their environmental which produces toxic compounds in the environmental medium of this material. To this end we investigated in this direction by study of the inhibition of the phenomenon of corrosion of this material. Grapefruit oil extract (GO) was tested as corrosion inhibitor for mild steel in 1M HCl. Electrochemical impedance spectroscopy (EIS) method are used. The inhibiting action increases with the concentration of the tested inhibitor. The highest efficiency 86.15% is obtained at 1g/L of GO. Effect of temperature is also studied between 298 K and 328 K; GO presents best inhibition efficiency even at elevated temperature, GO is adsorbed on the steel surface according to a Langmuir isotherm adsorption model. The thermodynamic data of activation are determined. In this study fatty acid composition contents of Grapefruit were determined. The used methods indicate that the Grapefruit oil extract is a good inhibitor in 1.0 M HCl. Some thermodynamic functions of the carbon steel dissolution process in acid medium were also determined and discussed., Moroccan Journal of Chemistry, Vol 5, No 4 (2017)