Corrosion Protection of Carbon Steel in Acidic Solution by Using Ylang-Ylang Oil as Green Inhibitor

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

Triazole derivative as new and effective corrosion inhibitor for carbon steel in hydrochloric acid: Electrochemical and quantum chemical studies

The corrosion inhibition properties of triazole derivative via 3,4-diamino-1,2,4-triazole (TRD) were investigated by the electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods. The results of electrochemical research revealed that the TRD was adsorbed on the metal surface by adsorption mechanism and behave as mixed type inhibitor. The Among TRD exhibited maximum efficiency of 90% at 10-3M. The inhibition mechanism was analyzed by the potential of zero charge (Epzc) measurement at the solution/metal interface. The adsorption behaviour of the 3,4-diamino-1,2,4-triazole on Fe (110) surface was investigated by Monte Carlo simulations to verify their corrosion inhibition efficacies.

The SuperCam Instrument Suite on the Mars 2020 Rover: Science Objectives and Mast-Unit Description

On the NASA 2020 rover mission to Jezero crater, the remote determination of the texture, mineralogy and chemistry of rocks is essential to quickly and thoroughly characterize an area and to optimize the selection of samples for return to Earth. As part of the Perseverance payload, SuperCam is a suite of five techniques that provide critical and complementary observations via Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), visible and near-infrared spectroscopy (VISIR), high-resolution color imaging (RMI), and acoustic recording (MIC). SuperCam operates at remote distances, primarily 2-7 m, while providing data at sub-mm to mm scales. We report on SuperCam's science objectives in the context of the Mars 2020 mission goals and ways the different techniques can address these questions. The instrument is made up of three separate subsystems: the Mast Unit is designed and built in France; the Body Unit is provided by the United States; the calibration target holder is contributed by Spain, and the targets themselves by the entire science team. This publication focuses on the design, development, and tests of the Mast Unit; companion papers describe the other units. The goal of this work is to provide an understanding of the technical choices made, the constraints that were imposed, and ultimately the validated performance of the flight model as it leaves Earth, and it will serve as the foundation for Mars operations and future processing of the data.In France was provided by the Centre National d'Etudes Spatiales (CNES). Human resources were provided in part by the Centre National de la Recherche Scientifique (CNRS) and universities. Funding was provided in the US by NASA's Mars Exploration Program. Some funding of data analyses at Los Alamos National Laboratory (LANL) was provided by laboratory-directed research and development funds

Inhibition efficiency of two bipyrazole derivatives on steel corrosion in hydrochloric acid media

244-253The inhibitor effect of two isomers namely 2-(1',5,5'-trimethyl-1H,1'H-3,3'-bipyrazol-1-yl)ethanol (1-TBE) and 2-(1',5,5'-trimethyl-1H,2'H-3,3'-bipyrazol-2-yl)ethanol (2-TBE) on the corrosion of mild steel in 1.0 M hydrochloric acid has been investigated at 308 K using weight loss measurements and electrochemical techniques (impedance spectroscopy and polarisation curves). Inhibition efficiency is dependent upon the pyrazole structure, with 1-TBE serving as a better inhibitor than 2-TBE and its inhibition efficiency increases with the increase of concentration of inhibitor to attain 93% in the presence of 10-3M. Polarisation curves indicate that 1-TBE and 2-TBE act essentially as cathodic inhibitors. Efficiency (E) percent values obtained by various methods are reasonably good in agreement. EIS measurements show an increase of the transfer resistance with the inhibitor concentration. The temperature effect on the corrosion behaviour of steel in 1.0 M HCl without and with the inhibitor at 10-3M is studied in the temperature range 308-333 K, Some thermodynamic parameters such as adsorption heat (H°), adsorption entropy (S°) and adsorption free energy (G°) have been calculated by employing thermodynamic equations. Kinetic parameters such as apparent activation energy and pre-exponential factor have also been calculated. Adsorption of 1-TBE on the mild steel surface in 1.0 M HCl follows the Langmuir isotherm model

8-hydroxyquinoline grafted triazole derivatives as corrosion inhibitors for carbon steel in H2SO4 solution: Electrochemical and theoretical studies

The inhibition capacity of carbon steel (CS) in 0.5M H2SO4 by three 8-hydroxyquinoline grafted triazole derivatives (EHTC, AHTC, and MHTC) have been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PPD), and weight loss measurements (WLM) at 298 K. Generally, the results clearly show that the inhibition performance (η %) increases with an increase in the concentration of EHTC, MHTC, and AHTC, reaching a maximum value of 95.5% (EHTC), 95.1% (MHTC), and 94.1% (AHTC) at the optimal concentration (10−3 M) for PPD technical. The PPD shows that EHTC, AHTC, and MHTC behave as mixed-type inhibitors. In addition, the inhibitor obeys the single layer adsorption isotherm of Langmuir. Scanning electron microscopy (SEM) analysis of the CS has also been investigated and discussed. The theoretical calculations and MD simulations show a better correlation with the experimental results for the studied triazole derivatives.Scopu

Performance and computational studies of two soluble pyran derivatives as corrosion inhibitors for mild steel in HCl

The present study is aiming to explore the effect of 4-Hydroxy-6-methyl-3-(3-quinolin-8-yl-acryloyl)-pyran-2-one (HMQP) and 3-[3-(4-Dimethylamino-phenyl)-acryloyl]-4-hydroxy-6-methyl-pyran-2-one (DMPHP) on mild steel (MS) corrosion in acid solution (1 M HCl). The compound was tested at various concentrations (0.001–1 mM) and four temperatures (298, 308, 318, and 328 K) to determine the optimal concentration and temperature range for the best corrosion inhibiting effect. In evaluating the inhibition efficiency, weight loss measurement, potentiodynamic polarization measurement (PDP), electrochemical impedance spectroscopy, SEM/EDS and theoretical methods were used. The inhibition efficiencies increase with increase in concentration and decreases with temperature. The maximum inhibition efficiency was found 90% and 85.4% at 298 K in the presence of 1 mM of DMPHP and HMQP respectively. The experimental adsorption data obeyed the Langmuir isotherm model. The polarization parameters suggest that DMPHP and HMQP are mixed type inhibitors. The results of the EIS study suggest that these compounds inhibit corrosion by adsorption mechanism. A good correlation between theoretical and experimental results was obtained.Scopu

The inhibition of carbon steel corrosion in hydrochloric acid media using 2-[(5-methyl-isoxazol-3-yl)-methyl]-benzimidazole

Carbon steel corrosion inhibition in a hydrochloric acid solution by 2-[(5-methyl-isoxazol-3-yl)-methyl]-benzimidazole (MMB) has been studied by electrochemical techniques (PDP and EIS). Results showed that the inhibition efficiency increases with higher MMB concentration, and the maximum value of 86.6% was obtained at 10-3 M concentration. The prepared benzimidazole inhibitor showed higher inhibition efficiency upon raising the solution temperature from 303 to 333 K. Corrosion current density decreased from 660.9 µA cm-2 (blank) to 97.8 µA cm-2 (MMB) and charge transfer resistance increased from 20.2 Ω cm2 (blank) to 150.8 Ω cm2 (MMB). PDP studies showed that MMB is a mixed type inhibitor. The adsorption of this compound onto the carbon steel surface in a 1 M HCl solution followed the Langmuir adsorption isotherm, and the value of the standard free energy of adsorption ( ΔG° ads ) is associated to. © 2021, Sociedade Portuguesa de Electroquimica. All rights reserved