MOHAMED ELHADI Said

ZEBIRI Zakarya , KERBAB Anis

Etude des inhibiteurs de corrosion d’un acier en milieu acide

Steel reinforcement corrosion is the paramount cause of degradation in reinforced concrete, particularly in humid or marine environments. This electrochemical process deteriorates steel through interaction with water, oxygen, and aggressive ions, severely compromising structural integrity, shortening service life, and escalating maintenance costs. Initially, steel is protected by concrete's alkaline environment (pH > 12.5), which forms a passive oxide layer. However, this protection is compromised by the ingress of chloride ions, which disrupt the passive film and initiate corrosion. To combat this, preventive strategies like corrosion inhibitors—chemical compounds added in small concentrations—are employed to slow the electrochemical process.  This research consists of conducting an investigative study on certain chemical compounds and examining their effect on the corrosion of steel in concrete, with the aim of potentially selecting those that act as inhibitors from those that do not.

Citation

Mohamed elhadi Said , ,(3025-09-10), Effect of inhibitors on corrosion of structural steel and interaction in an aggressive environment,2ND INTERNATIONNAL CONFERENCE OF APPLIED PHYSICS AND CHEMISTRY,University of Health Sciences-Türkiye

A

Citation

Mohamed elhadi Said , ,(2025-12-14), Experimental studies on the corrosion inhibition of API 5L Gr B steel by four bis-DABCOnium salts in Sulfuric acid solution,The first International Conference of Chemistry and Physics (1st-ICCP 2025) i,Faculté des Sciences Exactes Université Constantine 1

A

Citation

Mohamed elhadi Said , ,(2025-11-18), effect of Ficus carica extract ( FCE) on the corrosion of API L5 grade B steel,The Second International Conference on Chemistry Science, Materials Design and their applications ICCSM’2025 – HYBRID,The Second International Conference on Chemistry Science, Materials Design and their applications ICCSM’2025 – HYBRID

The inhibition efficiencies determined by gravimetric are in good agreement with electrochemical measurements (EIS and polarization methods) and the corrosion inhibition efficiencies rise with the concentration of EtbDBr, PrbDBr, BubDBr and PebDBr and exceed 95% at 298°K at 5 × 10–3M. The tested compounds that were found to be a mixed type can be effectively used as corrosion inhibitors for steel in sulfuric acid and the efficiency dependent on the spacer chain size linked to nitrogen atoms. The adsorption on the metal surface matched the Langmuir adsorption isotherm and the inhibition efficiencies decreased with temperature.

Citation

Mohamed elhadi Said , , (2025-06-26), Experimental studies on the corrosion inhibition of API 5L Gr B steel by four bis-DABCOnium salts in sulfuric acid solution, Anti-Corrosion Methods and Materials, Vol:73, Issue:1, pages:133-145, https://www.emerald.com/

Heavy metals can accumulate in water, including geothermal sources, posing potential environmental and health risks. This study investigated trace elements in geothermal waters of El Athmania, M’laa town, Algeria, to assess heavy metal concentrations. Water samples were collected in glass bottles and analyzed using X-ray fluorescence (XRF) spectrometry. Preconcentration was performed using evaporation at 80°C and Amberlite XAD-7 resin, followed by DRX analysis. Concentrations of metals measured included Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Ba, and Pb. The average abundance order was: Cu » Mn > Zn > Cr > Ni > Fe. Correlation matrices and principal component analysis (PCA) indicate that these metals likely originate from similar sources, consistent with soil erosion processes. Regular monitoring of heavy metals in geothermal waters is recommended to prevent excessive accumulation and potential health risks. Keywords: Geothermal water; Heavy metals; Amberlite XAD-7; X-Ray Fluorescence (XRF).

Citation

Mohamed elhadi Said , ,(2025-05-21), Evaluation of Trace Elements in Geothermal Waters of El Athmania, Algeria,The Second International Seminar on Catalysis, Chemical Engineering & Green Chemistry (CACEG 2025),University of El Oued, Algeria

This work examines the efficiency of four bis-isoQuinolinium compounds in preventing the corrosion of A283 Grade C steel in a 0.5 M H2SO4 solution. The performance of these corrosion inhibitors was examined at various concentrations using weight loss, electrochemical impedance spectroscopy, and potentiodynamic polarization. Using gravimetric weight loss, the efficiency (IE%) reached a high value of 97.32, 98.14, 97.94, and 98.14% when the concentration reached 5 mM of bis-isoQuinolinium salts EtiQuiBr, PriQuiBr, BuiQuiBr, and PniQuiBr, respectively. According to the different investigations, the bis-isoQuinolinium salts are mixed-type inhibitors with slight predominance of cathodic inhibition. The adsorption of all studied inhibitors on the metal surface of A283 Grade C mild steel followed the Langmuir adsorption isotherm and the inhibition efficiencies decreased with temperature. The thermodynamic parameters, such as Ea, Kads, and ΔG°ads were determined. The negative values of ΔG°ads suggested a favorable adsorption of all inhibitors on steel surface. The order of IE determined from experimental measurements is: EtiQuiBr < PriQuiBr < BuiQuiBr < PniQuiBr. Furthermore, microscopic surface analyses, such as SEM and AFM were used to characterize the surface morphology of the steel specimens. Moreover, the Density Functional Theory (DFT) calculations were performed to correlate the electronic molecular structure of the studied inhibitors with their inhibition efficiency. The tested compounds can be effectively used as corrosion inhibitors for steel in sulfuric acid and the findings of this work shed more light on the corrosion inhibition of steel by ammonium salts in acidic medium.

Citation

Mohamed elhadi Said , Bureau de la stratégie de numérisation , , (2025-02-23), Corrosion inhibition of bis-isoQuinolinium salts derivatives for mild steel A283 Grade C in sulfuric media: an experimental and theoretical investigation, Journal of Dispersion Science and Technology Latest Articles, Vol:47, Issue:, pages:1-22, Taylor & Francis

The inhibition of API 5L Grade B steel corrosion in sulfuric acid solution in the presence of some pyridinium salt derivatives such as 1,1′-methylenebis(pyridin-1-ium)bromide (pyridinium salt 1) and 1,1′-(ethane-1,2-dyl))bis(pyridin-1-ium)bromide (pyridinium salt 2) was conducted using weight loss techniques, potentiodynamic polarization methods, electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM) and theoretical calculations. Various parameters were determined and discussed to fully understand the mode of action of these compounds, including thermodynamic activation, adsorption, and quantum chemical parameters. The results obtained by all techniques revealed that these derivatives are suitable inhibitors for this type of steel in sulfuric acid solutions. In addition, the inhibition efficiency increases with pyridinium salt concentration and temperature. The polarization curves show that both pyridinium salts are mixed-type inhibitors. Electrochemical impedance spectroscopy (EIS) indicates that charge transfer controls the corrosion process of steel in the absence and presence of compounds. The adsorption of each compound occurs via electrostatic and chemical bonds and obeys Langmuir’s adsorption isotherm. AFM images demonstrate that these salts protect this steel in H2SO4 solution. Theoretical calculations indicate a correlation between the experimental and quantum parameters.

Citation

Mohamed elhadi Said , , (2024-07-20), An experimental and theoretical study of two pyridinium salt derivatives as API 5L Grade B steel corrosion inhibitors in H2SO4 solution, International Journal of Corrosion and Scale Inhibition, Vol:13, Issue:3, pages:1520-1540, The Publication Ethics

The title benzimidazole compounds, namely, 2-(4-methoxynaphthalen-1-yl)-1H- benzo[d]imidazole, C18H14N2O(I) and 2-(4-methoxynaphthalen-1-yl)-1-[(4- methoxynaphthalen-1-yl)methyl]-1H-benzo[d]imidazole ethanol monosolvate, C 30H24 N2 O2 ·C2 H6 O(II), were synthesized by the condensation reaction of benzene-1,2-diamine with 4-methoxynaphthalene-1-carbaldehyde in the ratios 1:1 and 1:2, respectively. In I, the mean plane of the naphthalene ring system is inclined to that of the benzimidazole ring by 39.22 (8)° , while in II, the corresponding dihedral angle is 64.76 (6)° . This difference is probably influenced by the position of the second naphthalene ring system in II; it is inclined to the benzimidazole ring mean plane by 77.68 (6)° . The two naphthalene ring systems in II are inclined to one another by 75.58 (6)° . In the crystal of I, molecules are linked by N—H...N hydrogen bonds to form chains propagating along the a-axis direction. Inversion-related molecules are also linked by a C—H... interaction linking the chains to form layers lying parallel to the ac plane. In the crystal of II, the disordered ethanol molecule is linked to the molecule of II by an O—HN hydrogen bond. There are a number of C—H... interactions present, both intra- and intermolecular. Molecules related by an inversion centre are linked by C—H... interactions, forming a dimer. The dimers are linked by further C—H... interactions, forming ribbons propagating along the b-axis direction. The interatomic contacts in the crystal structures of both compounds were explored using Hirshfeld surface analysis. The molecular structures of I and II were determined by density functional theory (DFT) calculations at the M062X/6-311+g(d) level of theory and compared with the experimentally determined molecular structures in the solid state. Local and global reactivity descriptors were computed to predict the reactivity of the title compounds. Both compounds were shown to exhibit significant anticorrosion properties with respect to iron and copper.

Citation

Mohamed elhadi Said , , (2023-06-23), Synthesis and crystal structures of two 1H-benzo[d]¬imidazole derivatives: DFT and anti¬corrosion studies, and Hirshfeld surface analysis., Acta Crystallographica Section C-Structural Chemistry, Vol:79, Issue:7, pages:292-304, Wiley Online Library

The ability of (2-methoxy-2-oxoethyl)quinolinium bromide (Qui+ , Br- ) and (2-methoxy-2- oxoethyl) iso quinolinium bromide (isoQui + , Br- ) were investigated for corrosion inhibition of mild steel E24 in H2SO4 by impedance spectroscopy and potentiodynamic polarization measurements. A series of experiments with various inhibitor concentrations were conducted. The results show that the corrosion rate decreases, inhibition efficiencies increase, and surface coverage increase with increasing inhibitor concentration. Potentiostatic polarization revealed that both inhibitors affected cathodic and anodic reactions, making them inhibitors of a mixed type with a significant cathodic inhibitory character. Several adsorption isotherms, including Langmuir, Temkin, and Frumkin, were investigated to understand the inhibitor’s adsorption behaviour. The adsorption of both compounds on a mild steel surface obeys Langmuir’s adsorption isotherm. In addition, the values of showed a physisorption effect for the two prepared inhibitors. To compare the chemical reactivity of Qui + , Br- and isoQui+ , Br- and study the interactions between inhibitor molecules and the steel surface, different quantum chemical descriptors have been calculated, such as EHOMO, ELUMO, ΔE, χ, η, σ and ΔN. The results obtained reveal that the Qui+ , Br- has higher electronegativity (χ), global softness (σ), and global electrophilicity (ω) than the isoQui + , Br – compound. The order of IE determined from experimental measurements is successfully supported by theoretical analysis.

Citation

Mohamed elhadi Said , , (2023-06-08), Experimental and theoretical evaluation of (iso)quinolinium bromide derivatives as corrosion inhibitors of steel E24 in 0.5 M H2SO4 solution, International Journal of Corrosion and Scale Inhibition, Vol:12, Issue:2, pages:679-695, The Publication Ethics

The title compound Schiff base (SB) named: (6E)-3-benzyloxy-6- [ [ [2‑hydroxy-1,1-bis(hydroxymethyl)ethyl] amino]methylene]cyclohexa-2,4‑dien-1-one(I) (C18 H21 N O5), was synthesized via the reaction of 4-benzyloxy- 2‑hydroxy-benzaldehyde with 2-amino-2-(hydroxymethyl)propane-1,3-diol (Trizma)and characterized by single- crystal diffraction XRD, infrared spectra, H and 1 13C NMR spectroscopy. It crystallizes as a zwitterion, (E)-5- (benzyloxy)-2-(((1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl)iminio)methyl)phenolate (II), with the phenolic H atom having migrated to the imino group. Additionally,Hirshfeld surface analysis (HS), two-dimensional fingerprint plots and energy frameworks of II were calculated to quantify the interatomic interactions present in the crystal.The antioxidant activity of the synthesized compound was evaluated by five tests: ABTS, DPPH, O- pH, SNP and reducing power activity. Furthermore, molecular docking calculations were performed for SB compound at the active site of mushroom tyrosinase (PDB ID:2Y9X) to determine the binding affinity between the title compound and receptor protein. Results reveal a great affinity (-6.16 kcal/mol) of the SB to the protein that is mainly dominated by hydrogen bonds. In this work, experimentally, the assessment of the anti-corrosion ability of this compound by different methods showed excellent inhibition. On the other hand, anti-corrosion potentials of title compound have been investigated using density functional theory (DFT) in gas and solvent phases. Chemical reactivity descriptors like global hardness (η), chemical potential (u), electronegativity (χ), electrophilicity (ω) and number of transferred electrons (ΔN) were computed at ωB97XD with 6–311+g(d) basis set. The local reactive sites on this compound were studied using Fukui indices, local philicity index and dual descriptor. The quantum chemical calculation suggests a good charge transfer tendency from the title compound to the low-lying vacant d-orbitals of iron (The average value of charge transfer is ΔNIII/Fe.≈ 2.21 and ΔNIII/Cu.≈ 0.07). The C7 atom is the nucleophilic sites (Δf(r)C7 ≈ 0.25) on the inhibitor for effective interaction on the metal surface as shown by local reactive descriptor in gas and solvent. Furthermore, the results obtained from DFT and TD-DFT studies are in excellent agreement with experimental data (structure geometry (RMS Error ≈ 0.3 Å), optical properties (λexp-Cal ≈18 nm) and inhibition efficiencies

Citation

Mohamed elhadi Said , , (2023-04-14), Synthesis, Crystal structure, Hirshfeld surface interactions, anti-corrosion analysis, DFT calculations, Docking studies and evaluation of the antioxidant activity of a new zwitterion Schiff base, Journal of Molecular Structure, Vol:1286, Issue:, pages:135569, https://www.elsevier.com/locate/molstr

[dimOHmIm]+,I- and [dimOHmBim]+,I- were investigated as a corrosion inhibitors for MS in 0.5 M H2SO4 using gravimetric, PDP and EIS techniques. Polarization curves revealed that both compounds acted as mixed-type inhibitors, and that corrosion IE% increased with their higher concentrations. The adsorption of both inhibitors onto the MS surface obeyed Langmuir’s isotherm. The compound II showed a higher corrosion IE% than that of I. The quantum chemical calculations were applied to investigate the relationship between the two azolium salts derivatives electronic properties and their corrosion IE%. Keywords: imidazolium and benzimidazolium salts, MS, polarization, EIS, WL and corrosion inhibition.

Citation

Mohamed elhadi Said , , (2023-01-05), Experimental Evaluation and Theoretical Study of Imidazolium and Benzimidazolium Derivatives as Corrosion Inhibitors of Mild Steel in a 0.5 M H2SO4 Solution, Portugaliae Electrochimica Acta., Vol:41, Issue:2, pages:81-101, SCOPUS

EFFECT OF PELARGONIUM GRAVEOLENS LEAVES EXTRACT ON ZINC CORROSION IN HYDROCHLORIC ACID

Citation

Mohamed elhadi Said , ,(2022-10-19), EFFECT OF PELARGONIUM GRAVEOLENS LEAVES EXTRACT ON ZINC CORROSION IN HYDROCHLORIC ACID,International Seminar on Valorization of Agronomic, Ecological and Food Resources (ISVAEFR 2022) 18, 19 & 20 October 2022,University August 20, 1955 Skikda

VITIS VINIFERA L. SEEDS AS A SOURCE OF CORROSION INHIBITOR FOR ZINC AND ALUMINIUM

Citation

Mohamed elhadi Said , ,(2022-10-18), VITIS VINIFERA L. SEEDS AS A SOURCE OF CORROSION INHIBITOR FOR ZINC AND ALUMINIUM,International Seminar on Valorization of Agronomic, Ecological and Food Resources (ISVAEFR 2022) 18, 19 & 20 October 2022,University August 20, 1955 Skikda

PUNICA GRANATUM AS A NATURAL SOURCE OF CORROSION INHIBITOR FOR ZINC IN HYDROLIC ACID

Citation

Mohamed elhadi Said , ,(2022-10-18), PUNICA GRANATUM AS A NATURAL SOURCE OF CORROSION INHIBITOR FOR ZINC IN HYDROLIC ACID,International Seminar on Valorization of Agronomic, Ecological and Food Resources (ISVAEFR 2022) 18, 19 & 20 October 2022,University August 20, 1955 Skikda

In this work, we studied the corrosion protection efficiency of three pyridinium salts on steel (API 5L Gr.B) in 0.5 M H2SO4 solution. Gravimetric and electrochemical methods were employed. We conducted investigations at various concentrations of the studied inhibitors and experiment temperature. The morphological of the steel surface was accomplished using scanning electron microscopy. Weight loss shows that an increase in the concentration of inhibitors A and C does not have any notable influence on the inhibition efficiency from 0.5 mM. However, the inhibition efficiency increases significantly with the increase of inhibitor B concentration. The values of (IE%) determined from EIS for these inhibitors follow the order: A ≈ C > B and the most excellent inhibition efficiencies are 97.88%, 86.96%, and 97.65%, respectively at 5 mM and all studied inhibitors are mixed-type inhibitors. In addition, the adsorption of the inhibitor molecules on the steel surface is reliable on the Langmuir adsorption isotherm model and the adsorption mechanism occurs through the combination of three aspects of interactions (physisorption, chemisorptions and retro-donation). IE% values of A, B and C inhibitors determined from EIS increase very slightly with temperature increase; the protective properties are excellent even at 55 °C (98.37% for A, 92.18% for B and 98.78% for C). This investigation is completed by a theoretical calculation of some quantum chemical parameters using the Gaussian09 program. The order of IE determined from experimental measurements is successfully supported by surfaces analysis and the obtained results confirmed an excellent concordance between potentiodynamic polarization, weight loss, EIS and theoretical study. Keywords: Pyridinium saltsteelelectrochemical methodsweight losscorrosion

Citation

Mohamed elhadi Said , , (2021-11-30), Experimental and theoretical study on corrosion inhibition of pyridinium salts derivatives for API 5L Gr.B steel in acidic media, Journal of Adhesion Science and Technology, Vol:36, Issue:20, pages:2245-2268, taylor and francis