Showing papers by "Belkheir Hammouti published in 2020"

Eco-friendly Chamaerops humilis L. fruit extract corrosion inhibitor for mild steel in 1 M HCl

Abstract: Given the great interest in the application of medicinal and aromatic plants in several fields, including the control of corrosion of metals in different environments and in order to minimize the use of synthetic inhibitors, this is the objective of our research. In this work, ethanol and hexane extracts of Chamaerops humilis L. fruits were investigated as green corrosion inhibitors for mild steel in 1 M HCl solution. Corrosion rates were evaluated at 308 K using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Electrochemical techniques reveal that ethanol and hexane extracts exhibit excellent inhibition efficiency indicated that the corrosion mechanism is controlled by charge transfer process and function as mixed type inhibitors at temperature studied. Adsorption studies showed that the process follows the Langmuir adsorption isotherm. The weight loss measurements show that ethanol and hexane extracts of Chamaerops humilis L. fruits are excellent inhibitors in 1 M HCl medium and its inhibition efficiency (%IE) increases with an increase in the concentration of the inhibitors and reaches 88% and 80% at concentrations of 1 g/l of ethanol and hexane extracts, respectively. The mechanism for inhibiting corrosion of mild steel by ethanol and hexane extracts of Chamaerops humilis L. fruits has been proposed.

DFT Theoretical Study of 5-(4-R-Phenyl)-1H-tetrazole (R = H; OCH3; CH3; Cl) as Corrosion Inhibitors for Mild Steel in Hydrochloric Acid

Abstract: Quantum chemical study, based on DFT methods at B3LYP/6-31G (d, p) level of theory, of four tetrazole compounds, denoted Ph-T, Me-Ph-T, MeO-Ph-T, Cl-Ph-T and reported as corrosion inhibitors in acidic medium, has been investigated in an attempt to find relationships between their molecular electronic properties and their corresponding experimental corrosion inhibition efficiencies. The global reactivity descriptors, such as the frontier molecular orbital energies (EHOMO and ELUMO), energy gap ∆E, electronegativity χ, absolute hardness η and softens σ, fraction of electrons transferred ∆N as well as local selectivity parameters such as Natural Atomic Populations and Fukui indices were also calculated and discussed. The calculations were undertaken in both gaseous and aqueous states for a better approach of the experimental conditions. The results showed that Cl-Ph-T presented the lowest ELUMO and the highest χ indicating its high electron acceptor ability, which can explain its good corrosion inhibition efficiency when compared to the three-other studied tetrazole derivatives.

Synthesis, characterization, anti-corrosion behavior and theoretical study of the new organic dye: 3-oxo-3H-spiro[isobenzofuran-1,9´-xanthene]-3´,6´-diyl bis(3-methyl-benzenesulfonate)

Abstract: The present work covers the recent synthetic of 3-oxo-3H-spiro[isobenzofuran-1,9 ́-xanthene]3 ́,6 ́-diyl bis (3-methylbenzenesulfonate) in high yield attain 91% through reaction between fluorescein and 4-methylbenzenesulfonyl chloride for 8 hours under different operating conditions. We have developed an environmentally friendly compound, mild condition protocol and convenient procedure for the preparation of this xanthene derivative. The structure of the new organic dye was determined by spectroscopic methods such as: H NMR, C NMR, infrared and MS data. This reaction has been studied also theoretically using Gaussian 09 software based on the DFT method at B3LYP/6-31G(d,p), in order to explain the possibility of these reaction through the quantum chemical parameters. The results obtained theoretically are in good correlation with those obtained experimentally. The inhibition effect of 3-oxo-3Hspiro[isobenzofuran-1,9 ́-xanthene]-3 ́,6 ́-diyl bis(3-methyl-benzenesulfonate (NAR1) on the corrosion of mild steel in molar hydrochloric acid solution. The experimental part was performed by studying the stability of the synthetic product in the corrosive medium and the inhibition behavior was investigated using absorbance difference measurements; the result indicates that NAR1 is a good inhibitor in acidic medium at low concentration at 1 ppm, the percentage of inhibition efficiency achieves 93%. The surface analysis of mild steel was investigated using scanning electron microscopy (SEM) and Energy dispersive X-ray (EDX) methods and show the adsorption behavior of inhibitor on the surface of mild steel.

The environmental management system and its application impacts on the business economy in the eastern region of morocco

Abstract: Nowadays, the environment occupies more and more a priority thought for the public opinion as well as for the local authorities, the administrations and the companies. Environmental management improves the performance of any organization towards the environment. In this perspective, our work consists in developing a dashboard grouping all the environmental indicators and which can have a direct or indirect impact on the economic performance of the company starting from the implementation of an environmental management system based on the ISO 14001 standard. This table can serve as an environmental decision support tool while also analyzing the results of monitoring. This approach, key for sustainable development, is encouraged by public authorities and Moroccan economic actors.

New strategy of synthesis, characterization, theoretical study and inhibition effect on mild steel corrosion in acidic solution

Abstract: We report two new different synthesis strategies of an eco-friendly organic dye 3-oxo-3H-spiro[isobenzofuran-1,9'-xanthene]-3',6'-diyl diacetate. These methods were based on the reaction of fluorescein with acetic anhydride under different experimental conditions. The synthesized heterocyclic system obtained with excellent yield was characterized by FT-IR, 1 H N.M.R., 13 C N.M.R., and mass spectrometry. This reaction has also been studied theoretically using Gaussian 09 based on the DFT method at B3LYP/6-31G (d, p). The results obtained are in good correlation with those obtained experimentally. The inhibition behavior of the synthetic product has been studied using absorbance difference measurement, the percentage of inhibition efficiency attains 90% at 10 -4 M of NAR3 inhibitor. The surface analysis of mild steel was investigated using scanning electron microscopy (S.E.M.) and Energy Dispersive X-ray (E.D.X.) methods and show the adsorption behavior of inhibitor on the surface of mild steel.

Reactivity and Fe complexation analysis of a series of quinoxaline derivatives used as steel corrosion inhibitors

Abstract: The B3LYP/6-31G(d,p) calculations were conducted to establish a correlation between structural electronic properties and corrosion inhibition efficiencies of four quinoxaline derivatives. The Fukui functions reflecting the local reactivity centers were investigated to determine the Fe-complexes by the studied ligands. Three spin multiplicities were examined and the quintet complexes were the most stable. Five types of interactions between Fe and quinoxaline compounds were studied, i.e., Fe–2S, Fe–2O, Fe–ϕ, Fe–S, and Fe–O among 10 complexes. While the calculated binding energies of the chelating bidentate complexes Fe–2O/2S were the lowest, Fe–ϕ presented a higher energy value without loss of aromaticity.

Monitoring heavy metal contamination levels and microbiological pollution in seawater of Agadir coastal zones

Abstract: The objective of this study was to monitor the bacteriological contamination of the seawater of the marine fisheries of the coastal Agadir, Morocco. The study was focused on the diagnosis on the pollution in heavy metals, such as cadmium, lead, and mercury in five zones: the port of Imi Ouaddar fish boarding (zone Z1), the old port of Agadir (zones Z2 and Z3), the port of Agadir Marina (zone Z4), and the estuary of Oued Souss (zone Z5). The analyses were done by testing physicochemical parameters (such as pH, temperature, dissolved oxygen, salinity and conductivity) as well as microbiological and atomic adsorption analyses. The experimental results showed that the values of the physicochemical parameters were almost the same in all zones, while the microbial conditions were different, in which this is due to the existence of heavy metals. The more heavy metal concentrations affected the condition of microbes in the sea water, confirmed by the number of Escherichia coli. This study demonstrated the importance of controlling concentration of heavy metals for better sustainability of environment. © 2020 Tim Pengembang Jurnal UPI Article History: Received 12 Apr 2019 Revised 25 Jun 2020 Accepted 28 Jun 2020 Available online 04 Jul 2020 __________________________

Investigation of spread of novel coronavirus (COVID-19) pandemic in MOROCCO & estimated confinement duration to overcome the danger phase

Abstract: Purpose: The objective of this paper is to make an investigation of spread of novel coronavirus (COVID-19) in MOROCCO and to estimate the duration of confinement for the fight against coronavirus disease 2019 (COVID -19). Methods: Data available on the sites provided by the Moroccan Ministry of Health, nonlinear regression, Gaussian function, residual sum of squares and regression curve. Results: Moroccan citizens must stay at home as much as possible until June 12, 2020. Conclusion: Given the non-existence of a vaccine or an effective treatment against the coronavirus (COVID-19), our research team believes that confinement remains the best solution to limit the spread of this pandemic.