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This work reports on an inhibition and adsorption performance study of two quinazoline derivatives ((2-(2-chlorophenyl)-2,3-dihydroquinazolin-4(1H)-one) and (2-(2,4- dichlorophenyl)-2,3-dihydroquinazolin-4(1H)-one)) named ZB3 and ZB4, which were synthesized and examined using carbon nuclear magnetic resonance (13C NMR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The assessment of the corrosion prevention of these two compounds for MS in 1.0 M HCl was performed employing potentiodynamic polarization (PDP) and (EIS) electronic impedance spectroscopy. The experiments performed showed that both derivatives operate well to prevent corrosion and their efficiencies exceed 85% at a concentration of 10-3. Moreover, it is discovered that the three chemicals' adsorption on the m-steel surface complies with Langmuir adsorption isotherm equation. The m-steel surface submerged in the corrosive solution was characterized by scanning electron spectroscopy (SEM) in conjunction with energy dispersive spectroscopy (EDS), spectroscopy using atomic force microscopy (AFM), X-Ray diffraction, and FTIR analysis. The findings showed that the examined inhibitors are well adsorbed, generating a barrier layer for the msteel's surface. DFT calculations and Monte Carlo (MC) simulation were used to directly correlate the electronic and adsorption properties, respectively, with the experimental corrosion inhibition efficiencies obtained for quinazoline and its 2 investigated derivatives. [ABSTRACT FROM AUTHOR]

The current study investigates the adsorption properties of a novel heterocyclic compound, 13-(4-chlorophenyl)-3, 3-dimethyl-3, 4-dihydro-1H-indazolo[1,2-b] phthalazine 1,6,11(2H,13H)-trione (DDIP), as an inhibitor against the oxidation of brass in hydrochloric acid solution. The experimental investigation included several methods, including EIS and PDP. The inhibition efficiency of the compound followed the order of 90.0%. The adsorption process of this inhibitor on the brass substrate followed the Langmuir adsorption model. SEM/EDS and XRD techniques were utilized to analyze surfaces, revealing the presence of a protective film overlaying the brass substrate. In addition, the results of DFT calculations of the DDIP compound revealed the existence of many active sites on the brass surface, facilitating the adsorption of our inhibitor. [ABSTRACT FROM AUTHOR]

In the present study, a simplest and most effective method was applied to removal of Cu2+ ions from an aqueous solution using Montmorillonite clay, nontoxic and abundantly available as an adsorbent. The used adsorbent was characterized using X-ray diffraction (XRD), the X-ray fluorescence spectrometry, Fourier Transform Infrared Spectroscopy (FT-IR) and scanning electron microscope (SEM) coupled with EDX analysis. Adsorption experiments were conducted under various conditions, i.e., contact time, initial concentration, pH of Cu(II) ions solution, adsorbent mass, and particle size. The results proved that the adsorption of Cu(II) ions by Montmorillonite clay was favorable at pH=5.5 with an extraction yield of 85% after 30 min contact. The equilibrium isotherm data were analyzed using the Langmuir and Freundlich equations. In all cases, the adsorption process fitted the second-order kinetics well, and the isotherm equation due to Freundlich showed good fits with the experimental data. In order to value our Cu-Montmorillonite clay (Cu-MC) support, we thought of applying it as recyclable heterogeneous catalyst for the condensation of Knoevenagel. The model reaction was carried out at room temperature, using a quantity of 0.5 mg of catalyst and a volume of 2ml of ethanol, the reaction yield was excellent (87%). The recyclable solid catalyst was effective for five successive cycles, indicating that this clay is a potentially eco-friendly heterogeneous catalyst. [ABSTRACT FROM AUTHOR]

• PY-2Cl and PY-2Cl act as effective inhibitors for MS acidic corrosion. • The adsorption of PY-2Cl and PY-2Cl followed the Langmuir isotherm model. • Adsorption on the surface is analyzed by AFM, SEM/EDS, XRD, and FTIR techniques. • Theoretical data provide in-depth understanding of the experimental results. The present paper examines the adsorption of two novel heterocyclic compounds of the pyran derivatives, namely, 2-amino-4-(2-chlorophenyl)-5-oxo-4,5-dihydropyrano[3,2-c]chromene-3-carbonitrile (PY-2Cl) and 2-amino-4-(4-chlorophenyl)-5-oxo-4,5-dihydropyrano[3,2c]chromene-3-carbonitrile (PY-4Cl) against the corrosion of mild steel (MS) in molar hydrochloric acid (HCl) medium. The experimental investigation was carried out utilizing a series of techniques including Weight Loss (WL), Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP). Results showed that inhibition effectiveness of PY-2Cl and PY-4Cl increases with their concentration. Polarization results showed that PY-2Cl and PY-4Cl displayed mixed type behaviour. Inhibition efficiencies of PY-2Cl and PY-4Cl followed the order: 85.8% (PY-4Cl) < 91.2% (PY-2Cl).The adsorption process of PY-2Cl and PY-4Clonto MS surface follows Langmuir adsorption model. Surface characterization analysis utilizing Scanning Electron Microscopy (SEM) coupled with Energy dispersive X-ray analysis (EDS), Atomic Force Microscopy (AFM)and Infrared Spectroscopy (FT-IR) supported the existence of a barrier layer covering the MS. WL measurements were also tested utilizing inductively coupled spectroscopy (ICP) and UV–vis spectrometry (UV–vis). [ABSTRACT FROM AUTHOR]

[Display omitted] • M2 and M3 act as effective inhibitors for steel acid corrosion. • The adsorption of M2 and M3 followed the Langmuir isotherm model. • adsorption on the surface is analyzed by AFM, SEM/EDS, XRD, and contact angle techniques. • Theoretical data provide in-depth understanding of the experimental results. In the current study, the adsorption of two new heterocyclic purine derivative compounds is investigated. namely, 7 H -purin-6-amine (Adenine) (M2) and 7 H -purin-6-amine (Adenine) (2R,3R,4S,5R) −2-(6-amino-9 H -purin-9-yl) −5-(hydroxymethyl) tetrahydrofuran-3,4-diol (M3) against the corrosion of mild steel in 1.0 M HCl medium. Weight Loss (WL), Electrochemical Impedance Spectroscopy (EIS), and Potentiodynamic Polarization (PDP) were among the techniques used in the experimental investigation. The respective inhibition efficiencies of M2 and M3 were found to be 89.0% and 96.5%.The Langmuir adsorption model was used to describe how M2 and M3 adsorb on the mild steel substrate. In addition, SEM/EDS, AFM, XRD, contact angle, and FT-IR techniques were employed to analyze the surfaces to support a protective film over the metal surface. Inductively coupled spectroscopy (ICP) was used to examine the WL observations as well. Furthermore, Molecular Dynamics (MD) simulations and DFT calculations were conducted to analyze the interaction of M2 and M3 with the mild steel substrate and their manner of adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Py-1 and Py-2 act as effective inhibitors for stainless steel in acidic solution and their effectiveness increases with their concentration. • Polarization results showed that all compounds displayed anodic-type behavior. Inhibition efficiencies of Py-1 and Py-2 followed the order: 90.9% (Py-2) < 96.7% (Py-1). • Adsorption of both studied pyrazole obeys Langmuir adsorption isotherm. • Adsorption of the examined compounds on metallic surface was reinforced with SEM-EDAX studies. • DFT results suggested that Py-1 and Py-2 molecules have strong ability to transfer their electrons into d-orbitals of surface metallic atoms. The present paper examines the adsorption of two novel heterocyclic compounds of the pyrazole derivatives, namely, Ethyl 1-amino-3-(2-chlorophenyl)-5,10-dioxo-5,10-dihydro-1H-pyrazolo[1,2-b] phthalazine-2 carboxylate ( Py-1 ) and Ethyl 1-amino-5,10-dioxo-3-(p-tolyl)-5,10-dihydro-1H-pyrazolo[1,2-b] phthalazine-2-carboxylate ( Py-2 ) against the oxidation of stainless steel in 2.0 M H 2 SO 4. The EIS and PDP demonstrate that the inhibitory properties of both compounds under investigation grow with concentration. Inhibition efficiencies of Py-1 and Py-2 followed the order: 90.9% (Py-2) < 96.7% (Py-1). the intensity-potential curves show that Py-1 & Py-2 imparted high resistance and acted as anodic type inhibitors. According to the Langmuir Isotherm adsorption model, the tested inhibitors have been deposited on the stainless-steel surface. The impedance diagrams also include two semicircles, the first of which was linked to the development of protective inhibitor films and the second to the process of charge transfer. SEM/EDX analyses were performed to describe the chemical makeup of the layer that had formed on the steel's surface. Theoretical studies, such as MD simulation and DFT, have helped to better elucidate the understanding of the process of corrosion inhibition. [ABSTRACT FROM AUTHOR]

• PY-CH 3 and PY-H act as effective inhibitors for mild steel acidic corrosion. • The adsorption of PY-CH 3 and PY-H followed the Langmuir isotherm model. • Adsorption on the surface is analyzed by AFM, SEM/EDAX, XRD, and FTIR techniques. • Theoretical data provide in-depth understanding of the experimental results. The present paper examines the adsorption of two novel heterocyclic compounds of the pyran derivatives, namely 2-amino-5-oxo-4-(p-tolyl)-4H,5H-pyrano [3,2-c]chromene-3-carbonitrile (PY-CH 3) et 2-amino-5-oxo-4-phenyl-4H,5H-pyrano [3,2-c]chromene-3-carbonitrile (PY-H)against corrosion of mild steel in molar HCl medium. The experimental investigation was carried out using several techniques including Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP). The inhibition efficiencies of PY-CH 3 and PY-H followed the order: 80.0% (PY-CH 3) < 90.0% (PY-H). The adsorption process of PY-CH 3 and PY-H on the mild steel surface follows Langmuir adsorption model. Surface characterization analysis using Scanning Electron Microscopy (SEM) coupled with Energy dispersive X-ray analysis (EDS), Atomic Force Microscopy (AFM), X-ray diffraction analysis (XRD), and Infrared Spectroscopy (FT-IR) supported the formation of a barrier layer that covers the mild steel surface. WL measurements were also tested using inductively coupled spectroscopy (ICP) and UV-Vis spectrometry (UV-Vis). The interaction mechanism of PYCH 3 and PY-H with mild steel surface and their mode of adsorption were studied using DFT and Monte Carlo (MC) simulations, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]