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Water contamination is a major health issue that can be addressed by using carbonaceous materials to adsorb and filter pollutants, yet adsorption mechanisms need to be better understood to improve the adsorption efficiency. Here we review the models that are used to study the mechanisms of adsorption of drugs, dyes and metal ions on carbonaceous materials, with emphasis on classical and advanced isotherms. We discuss the fitting frequency, lignocellulosic and fossil fuel-derived adsorbents, biomass composition, activating agents, surface functions, the carbonization temperature, the medium temperature effect and the use of several isotherms to explain the same mechanism. The adsorption capacity can reach up to 2651 mg of contaminant per g of lignocellulosic materials and 1274 mg of contaminant per g of fossil materials. Isotherm validation commonly depends on several parameters. The adsorption on lignocellulosic carbonaceous materials is best described by the Langmuir isotherm. In contrast, adsorption on fossil materials is best described by the Redlich-Peterson isotherm. Advanced and classical isotherms are in good agreement in 44% of reports. [ABSTRACT FROM AUTHOR]

• Synthesis and spectroscopic characterizations of new bis-isoxazoline-thiosemicarbazone molecules. • With an optimal dose (0.77 mM), the inhibition efficiency reached 95 % at 298 K in 1 M HCl. • Polarization measurements indicate that compound 3 exhibits a mixed-type corrosion inhibition mechanism. • DFT calculations and the dynamic monte carlo data simulations demonstrated the adsorption studies of compound 3 on the iron surface. • Theoretical simulations confirmed the consistency between the experimentally obtained data, thus enhancing the reliability of the observed results. In this study, a novel compound, bis-isoxazoline-thiosemicarbazone (BIT), was synthesized and tested for its ability to protect carbon steel from corrosion in a 1 M HCl solution. The compound's structure was confirmed using spectroscopic techniques such as 1H NMR, 13C NMR, and HRMS. Various methods, including mass loss analysis, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), SEM, and EDX, were employed to assess BIT's effectiveness in inhibiting corrosion and its adsorption behavior on carbon steel in acidic conditions. The findings demonstrated the high effectiveness of BIT as a corrosion inhibitor, with a 95 % inhibition rate observed at a concentration of 0.77 mM and a temperature of 298°K. Analysis through PDP revealed that BIT operates as a mixed-type inhibitor, conforming to the Langmuir adsorption isotherm during its attachment to the carbon steel surface, indicating a mixed (chemical-physical) adsorption process. SEM-EDX analysis demonstrated even distribution of the inhibitor on the steel surface. Notably, BIT contains several functional groups (methoxy, carbonyl, isoxazolyl,..) and heteroatoms (N, O, and S) that play a crucial role, as supported by Density Functional Theory (DFT) studies. Experimental findings were validated by DFT and molecular dynamics (MD) simulation data. [Display omitted] [ABSTRACT FROM AUTHOR]

The inhibitory activity of the expired egg-white carbon steel (CS) extract in HCl solution was studied in this article. The extract was examined using FT-IR, and the surface was examined using a scanning electron microscope (SEM) and energy-dispersive X-ray analysis (EDX). Weight loss techniques at various temperatures were used to examine corrosion investigations (298, 308, 318, and 328 K), concentrations (100, 200, 400, and 800 mg. L−1) of extracts, and electrochemical measurements (potentiodynamic polarization (PDP) and impedance spectroscopy (EIS) at 25°C and different concentrations. Results. Results obtained through EIS demonstrated a maximal inhibition efficiency of 90% at an inhibitor concentration of 800 mg. L−1. Moreover, the findings of the potentiodynamic polarization indicated that egg-white extract was a mixed type of inhibitor and slowed down both cathodic and anodic reactions. For weight loss analysis, an inhibitory potency (89, 83, 77, and 71%) at various temperatures (298, 308, 318, and 328 K) was demonstrated, respectively. It indicates that the temperature rise contributes to a decrease in the resistance of the carbon steel. The adsorption of the expired egg-white extract was spontaneous with physisorption and chemisorption according to the Langmuir isotherm model, according to adsorption isotherm studies. [ABSTRACT FROM AUTHOR]