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The present article aims to investigate the effect of electrostatic field and temperature on the distribution of chloride and sodium ions during the saltwater flow in a horizontal channel. The change in the intensity of the uniform electric field has been controlled by applying DC high-voltage between the horizontal walls of the channel, where this field creates an electric force that deviate the positive and negative ions towards the walls in opposite directions, which results a large space in the middle of fluid almost free of dissolved salt. The proposed study is formulated with a system of coupled partial differential equations in the Navier-Stokes equation and energy. In addition, the Buongiorno equation was used to study the distribution of ion concentration in seawater. Important results were obtained in this numerical study, including that the increase in the intensity of the electric field and temperature significantly reduced the concentration of cations and anions in a wide area of seawater, thus obtaining a large amount of diluted water. The distribution of sodium and chloride ion concentration, the flow, the horizontal velocity, and the isotherms were modeled under the electrostatic field intensity variation factor and Reynolds number for an accurate, detailed, and clear interpretation. [ABSTRACT FROM AUTHOR]

For carbon steel (CS) in a corrosive hydraulic acid solution, various quantities of the molecule 3-phenyl-isoxazoline-carvone (PIC) were employed (1M; HCL). The inhibitory effects of the 3-phenyl-isoxazoline-carvone (PIC) were evaluated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), weight loss, surface morphology analysis (SEM), quantum chemical calculations (DFT), and Monte Carlo simulations (MC). According to the findings, the compound, 3-phenyl-isoxazoline-carvone (PIC) is a mixed-type inhibitor that significantly decreased the rate of carbon steel (CS) corrosion by creating a protective coating on the carbon steel surface (CS). According to EIS, PDP, and mass loss studies, the molecule 3-phenyl-isoxazoline-carvone (PIC) is a stronger corrosion inhibitor, with corrosion effectiveness of about 95% at 298 K temperature. Adsorption of the 3-phenyl-isoxazoline-carvone (PIC) molecule on the surface of carbon steel includes both physisorption and chemisorption, according to the Langmuir isotherm model. Aside from experimental methods, theoretical methods such as DFT simulations, molecular dynamics simulations, and the radial distribution method were used to provide detailed knowledge about the mechanism of corrosion inhibition and to reveal factors controlling the efficiency of the investigated inhibitor. [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]

This study deals with the treatment of synthetic effluent containing two textile dyes (reactive blue and disperse red 74) by electrocoagulation (EC) using iron electrodes. Then the results are compared with the performance of aluminum electrodes. Response surface methodology using the JMP.11 statistical experimental design was performed to design experiments and to optimize the process. Twenty experiments were conducted to study the effect of four important process parameters: current density (5-25 mA/cm²), initial pH (4-11), electrolyte concentration (1-5 g/L), and operating time (20-60 min) for the color removal efficiency (CRE) and consumption energy (CE). The parameters for maximum CRE and minimum CE were found with iron electrodes at current density 17.08 mA/cm², operating time 20 min, pH 9, and electrolyte concentration 2 g/L, for aluminum at 25 mA/cm², pH 4, operating time 60 min, and electrolyte concentration 2.5 g/L. Reactive and disperse dyes treated with iron electrodes shows efficiency in terms of color removal in alkaline solutions, compared with aluminum electrodes, and more efficiency was obtained in acidic solutions. The operating cost was calculated by considering the energy and electrode consumption and evaluated as 83.879 $/m³ of treated wastewater for iron electrodes and 126.23 $/m³ of treated wastewater for aluminum electrodes. SEM analysis was performed in further study and show the efficiency of the electrocoagulation process in dye removal. The findings of this study show also that chemical analysis and RSM are suitable for investigating the mechanism and optimization of EC as applied to textile effluents. [ABSTRACT FROM AUTHOR]

The objectives were to study the applicability of electrocoagulation (EC) for the denitrification of drinking water and to determine the main mechanisms of pollution removal. Electrolysis in the intensiostatic mode was applied to a synthetic water representative of potable water in which the concentration of nitrate ions was varied up to 200 mg/L. The respective influences of process parameters, initial concentration of nitrates, and initial pH were investigated. Experimental results show that EC removes efficiently nitrates, following first-order kinetics. A two-step mechanism was established: it consisted of the electroreduction of nitrates into ammonium on the cathode, followed by the adsorption of ammonium on the precipitated oxyhydroxides. Adsorption exhibited a zero-order mechanism. The rates of the two mechanisms were proportional to electrical charge loading and to the total amount of aluminum released in water, as current did not modify significantly the surface area of precipitates. However, adsorption was impaired by the increase of pH resulting from the electroreduction of nitrates, whereas the electrochemical step was insensitive to pH. While the electroreduction of nitrates is known to be far more expensive than biological denitrification, aluminum hydroxides formed during EC present interesting adsorption properties for ammonium removal. [ABSTRACT FROM AUTHOR]