Browsing by Author "Boudieb, Naima"

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Catalytic Activity of Phenol Oxidation over Iron and Cooper-Exchanged Pillared Bentonite
(Springer Nature, 2024) Chellal, Khalida; Hamidouche, Fahim; Boudieb, Naima; Meguellati, Zineb; Trari, Mohamed
Al, mixed Al–Fe and Al–Cu pillared clays were prepared by the conventional method in a diluted medium with two additional parameters for the synthesis; the first one is the cooling of the clay suspension and the second is the exchange between the clay and metal solutions before pillaring with the polymeric mixed solution. The solids were characterized by X-ray diffraction (XRD), N2 adsorption and H2-TPR. The effects of the atomic ratio (M/Al + M) and hydrolysis molar ratio (OH/M), on the basal spacing and/or the specific surface were examined. The exchange does not seem to fix more Cu as in the case of Fe. The dispersion of the cold clay suspension, before pillaring, leads to a greater basal spacing of the solid at room temperature. In the case of mixed Al–Fe exchanged and/or pillared clays calcined at 350 °C, the cold dispersion of the clay suspension increases the basal spacing from 15.89 to 17.44 Å and from 15.32 to 16.07 Å for MR-AlFe (10) and Fe/MR-AlFe (10) respectively. Catalytic Wet Peroxide Oxidation (CWPO) of phenol under mild conditions (25 °C, 1 atm) was carried out without correction of pH. Mixed Al–Fe and Al–Cu pillared clays have comparable performances, although they showed some differences in the H2O2 decomposition kinetics. A total conversion of H2O2 is obtained without the complete phenol conversion over mixed Al–Fe pillared clays suggesting the presence of active species in these catalysts. In a slight excess of H2O2, the activity increases for all Fe-based clays catalysts with increasing the Fe content. A total conversion of phenol was obtained within 15 h of reaction over Fe/MR-AlFe (10) and after extending the reaction time to 30 h in the presence of Fe/MR-Al. On the contrary, MR-AlFe (10) only converted 57.12% under the same conditions. MR-AlFe (10) has the greater basal space (17.44 Å) and is more active for H2O2 decomposition than Fe/MR-Al, which certainly allowed greater accessibility of the reactant to the Fe-species. Fe exchanged and post-pillared clay with mixed (Al–Fe) solution containing 10% Fe expressed as molar percentage {Fe/MR-AlFe (10)} was the most efficient for this reaction combining good catalytic activity with high stability against iron leaching (0.02%). It showed a total phenol degradation, the highest H2O2 decomposition (85.7%) and more than 80% of TOC removal after 15 h of reaction.
Effect of Hematite on the Energy Storage Performance of Polyaniline/Zeolite HY/α-Fe2O3 Nanocomposite Supercapacitor Electrode
(Springer, 2020) Ghebache, Zohra; Zitouni, Safidine; Hamidouche, Fahim; Boudieb, Naima; Benaboura, Ahmed; Trari, Mohamed
The main goal of the present work is the elaboration of new nanocomposite conducting poly(aniline) with α-Fe2O3 nanoparticles in the presence of zeolite HY acid in aqueous electrolyte by chemical oxidative polymerization. Various formulations of the polymer were synthesized (5, 10, and 20% of α-Fe2O3) and the nanocomposites poly(aniline)/HY/α-Fe2O3 have been characterized by X-ray diffraction (XRD), SEM analysis, and FT-IR spectroscopy. The electrical conductivity and the UV–visible spectroscopy of the nanocomposites were also investigated. In addition, the electrochemical properties were studied by cyclic voltammetry. (CV) and electrochemical impedance spectroscopy. The optimal ratio between α-Fe2O3 and poly(aniline)/HY was found to be 5 wt%. The specific capacitances of poly(aniline)/HY and nanocomposite were found to be be 630, and 1000 F g−1 respectively at a scan rate of 5 mV/s. Besides, the material possesses a high energy density of 88.88 Wh kg−1 and a maximum power density of 1632.3 W kg−1. These electrochemical results indicate that the PANI/HY/α-Fe2O3 nanocomposites is an attractive candidate for the application in the high-performance energy storage systems.
The effect of surfactants on the efficiency of lead acid batteries
(Elsevier, 2015) Boudieb, Naima; Bounoughaz, M.; Bouklachi, A.
The aim of this study is to show the effect of two phosphonate surfactants (PS) on the electrochemical behavior of the negative plate of lead-acid battery in the sulfuric acid medium. The characterization of the electrode interface was investigated at room temperature by a set of electrochemical techniques as linear sweep voltammetry (LSV), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA). Scanning electron microscopy (SEM) was employed to determine the film layer's morphology deposited on the surface of working electrodes, in the presence and in the absence of the PS. When the PS was added in the acidic solution, hydrogen evolution became higher, the over-potential of hydrogen was shifted to negatives values and the growth of the anodic β-PbO2 was inhibited. SEM imaging with the presence of PS showed reduction in the growth of the anodic β-PbO2 and PbSO4 layers. EIS results indicate the decrease of the conductivity of β-PbO2 film on the lead surface electrode. The result of the CV, show a decrease in the peak related to transition of PbO to Pb demonstrates that lower PbO has been formed underneath the lead sulfate membrane in the presence of low concentration of SP indeed a decrease in the amount of formed PbSO4 on the electrode surface
Effect of surfactants on the electrochemical behavior of the positive plate
(2016) Boudieb, Naima; Bounoughaz, M.; Bouklachi, A.
The main goal of this research is to improve the performance of positive plate of lead-acid battery using surfactants in 0.5 M H 2 SO . The use of surfactants aims to increase the ability and the cycle life of the positive active material. The electrochemical behavior of pure lead and PbO 4 electrodes interface was investigated at room temperature by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and potential-dynamic polarization curves. Scanning electron microscopy (SEM) was used to explore the film layer morphology deposited on the surface of working electrodes. Cyclic voltammograms of pure lead (Pb) electrode show that in the presence of PS the current peaks of the transition of PbO 2 to PbSO 4 and PbO 2 to PbSO 4 2 dropped at small concentrations of surfactants. We observed a remarkable improvement of the discharge capacity of the PAM for an amount of PS ranging between 10 and 50 ppm. EIS results indicate the improvement of mass transport by the decrease of resistance. In the other hand, the PbSO 4 surface layers and the crystal size of PbSO changes with impact effect of surfactants. As a result of the morphological changes which occurred, the PbO 4 films formed are hardly more reducible with PbSO 4 and delays the appearance of resistive PbSO layers at the material interface. As a conclusion, we can say that the electrical performance of the battery increase by extending the life cycle
Enhancing the Supercapacitive and Conductivity Properties of Polypyrrole via In-situ Polymerization with HY Zeolite Nanoparticles
(Springer link, 2020) Hamidouche, Fahim; Ghebache, Zohra; Boudieb, Naima; Sanad, Moustafa M. S.; Djelali, Nacer-Eddine
Highly stable zeolite HY/polypyrrole composite material was successfully fabricated by applying in-situ chemical polymerization approach. The functional properties of the prepared zeolite HY particles/polypyrrole were systematically inspected using XRD and FT-IR characterization techniques. Thermal stability and optical properties were consistently studied using TGA and UV–Vis spectroscopy techniques. The value of band gap energy (Eg) of the produced zeolite HY/polypyrrole nanocomposite was lower than the values of its individual components. Cyclic voltammetry studies concluded that HY/polypyrrole electrode material with mass ratio ~ 0.4 prepared at cold polymerization conditions ~ 0 °C exhibited the highest values of specific capacitance ~ 310 F g−1 and ionic conductivity ~ 1.7 S cm−1. The fabricated zeolite HY/polypyrrole composite material at 0 °C revealed a capacitance retention ~ 93.4%, while the other composite prepared at 25 °C possessed a capacitance retention ~ 72.4% after 500 charge/discharge cycles. The electrochemical impedance spectroscopy (EIS) measurement for the optimized composite electrode materials confirmed the cyclic stability after long term cycling of about 5000 cycles as a result of higher ionic conductivity between active material and ionic species than that value before cycling
Évaluation des performances des peintures par des technique électrochimique
(2008) Boudieb, Naima
La protection passive des installations métalliques contre la corrosion est assurée par les revêtements (organiques ou métalliques) et les peintures. Ces derniers limitent le flux des éléments agressifs en créant une barrière physique. La plupart des revêtements ne sont pas parfaits et par conséquent le contact métal/milieu corrosif est inévitable. L’efficacité des peintures anticorrosion est dépendante des caractéristiques intrinsèques du film organique (effet barrière), de son adhésion (interface métal/peinture), de la présence d’inhibiteurs ou de pigments sacrificiels au sein du film .Les objectifs de ce présent travail sont : l’étude de l’influence de la rugosité de la surface métallique sur la performance des revêtements époxydes et l’étude de l’effet des inhibiteurs organiques sur les propriétés barrières des peintures époxydes. L’étude du comportement à la corrosion et l’évolution du pouvoir protecteur des systèmes époxydes ont été réalisés par des techniques électrochimiques stationnaires (potentiel de corrosion, courbes de polarisation) et non stationnaires (spectroscopie d’impédance électrochimique, test de délamination cathodique). Ces méthodes permettent de mettre en évidence d’une part l’influence de l’état de surface sur la performance du système époxyde et d’autre part le rôle des inhibiteurs organiques dans les formulations des peintures de type époxyde
Influence de la composition des plaquettes en plomb (Pb) et du milieu sur le processus de charge et de décharge des batteries plomb-acide
(2018) Boudieb, Naima
Les trois grands domaines d’application des batteries au plomb-acide sont : les batteries de démarrage, les batteries de traction et les batteries stationnaires. La conservation de l'environnement et les évolutions des marchés, notamment celui de l’énergie, ouvrent de nouvelles applications de stockage par accumulateur au plomb acide : transports électriques, énergies renouvelables dont éolien et photovoltaïque, stockage réseau, secours...etc. Dans la plupart des cas, les contraintes d’application et l’amélioration des performances des batteries plomb-acide mènent à revoir profondément les mécanismes qui se déroule aux interfaces : collecteur de courant/matière active/électrolyte. Dans ce travail, nous avons mené différentes études sur les batteries au plomb-acide par des techniques électrochimiques : amélioration des performances des électrodes positives et négatives en ayant recours à l’ajout des molécules de surfactants à base des phosphonates à l’électrolyte de la batterie. L’ensemble des résultats a convergé vers une unique conclusion, à savoir que les plaques négatives et positives en cycles charge/décharge sont principalement limitées par les phénomènes de passivation, la corrosion, l’isolation électrique et ionique. La formation de PbSO4 sur les matières actives est un facteur responsable de la perte progressive du surface active des électrodes et de la perte prématurée de la capacité de l’accumulateur au plomb. Ces travaux montrent plusieurs avantages en termes d’amélioration importante de performance des plaques positives et négatives en cycles charge/décharge et la diminution de la sulfatation des cellules, qui conduit à l’augmentation de la surface spécifique des matières actives et à l’augmentation de la durée de vie des batteries. En plus, ces travaux de thèse vont permettre d’approfondir les connaissances sur la fabrication et le mécanisme de charge/décharge de l’accumulateur plomb-acide à des propriétés améliorées
Polycopié de cours Electrochimie fondamentale : Destiné aux étudiants Master I Chimie de l’environnement
(Université M’Hamed Bougara de Boumerdes-Algérie : Faculté des Sciences : Département de Chimie, 2024) Boudieb, Naima
L’électrochimie est aujourd’hui une science qui, bien qu’apparaissant de moins en moins explicitement sous cette appellation, se situe souvent en arrière-plan de nombreuses problématiques scientifiques actuelles. Que ce soit dans le domaine des énergies nouvelles avec les batteries, piles à combustible et autres cellules solaires, de la chimie « verte » avec l’électrocatalyse, des nano et neurosciences avec les ultramicroélectrodes et la microscopie électrochimique ou encore de l’électronique moléculaire avec les jonctions molécule-métal, l’électrochimie est bien souvent présente et la compréhension des phénomènes physico-chimiques qui régissent la problématique électrochimique est un passage obligé vers le développement de ces domaines à fort impact technologique et sociétal. C’est pourquoi il nous apparaît fondamental que l’électrochimie, située intrinsèquement à l’interface de multiples domaines de la physique et de la chimie et même de la biologie au travers de son utilisation.
Presence of Heavy Metals in Irrigation Water, Soils, Fruits, and Vegetables: Health Risk Assessment in Peri-Urban Boumerdes City, Algeria
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Aksouh, Mohamed Younes; Boudieb, Naima; Benosmane, Nadjib; Moussaoui, Yacine; Michalski, Rajmund; Klyta, Justyna; Kończyk, Joanna
This study investigates heavy metal contamination in soils, irrigation water, and agricultural produce (fruits: Vitis vinifera (grape), Cucumis melo var. saccharimus (melon), and Citrullus vulgaris. Schrade (watermelon); vegetables: Lycopersicum esculentum L. (tomato), Cucurbita pepo (zucchini), Daucus carota (carrot), Lactuca sativa (lettuce), Convolvulus Batatas (potato), and Capsicum annuum L. (green pepper)) in the Boumerdes region of Algeria. The concentrations of seven heavy metals (cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn)) in soil and food samples were analyzed using atomic absorption spectrometry. Health risks associated with these metals were evaluated through the estimated daily intake (EDI), non-carcinogenic risks (using target hazard quotient (THQ), total target hazard quotient (TTHQ), and hazard index (HI)), and carcinogenic risks (cancer risk factor (CR)). Statistical analyses, including cluster analysis (CA) and Pearson correlation, were conducted to interpret the data. The results revealed the highest metal transfer as follows: Cd was most significantly transferred to tomatoes and watermelons; Cr to carrots; Cu to tomatoes; and Fe, Ni, Pb, and Zn to lettuce. Among fruits, the highest EDI values were for Zn (2.54·10−3 mg/day) and Cu (1.17·10−3 mg/day), with melons showing the highest Zn levels. For vegetables, the highest EDI values were for Fe (1.68·10−2 mg/day) and Zn (8.37·10−3 mg/day), with potatoes showing the highest Fe levels. Although all heavy metal concentrations were within the World Health Organization’s permissible limits, the HI and TTHQ values indicated potential health risks, particularly from vegetable consumption. These findings suggest the need for ongoing monitoring to ensure food safety and mitigate health risks associated with heavy metal contamination.
Study of the Influence of Metal Surface Quality on the Performance of an Epoxy Coating
(Elsevier, 2023) Boudieb, Naima; Bounoughaz, Moussa; Hamidouche, Fahim; Ghebache, Zohra
In the present work, an EC used for steel corrosion protection was characterized by Ec techniques. This study aimed to describe the effect of the steel roughness surface on the performance of EC, through EIS and other methods. The studied metal was a low-strength CS immersed in a 3.5% NaCl solution. The CS surface was obtained by polishing it (metal electrodes) with an abrasive paper of 120, 600 and 1200 mesh. Then, the electrodes were painted with an anti-corrosive EC, which contained Zn3 (PO4)2 as an anti-corrosion agent. The study of the influence of the CS surface Ra and its corrosion behaviour and of the evolution of the protective capacity systems on the EC performance was made by stationary (Ecorr and Tafel plot) and no-stationary Ec techniques (EIS and CA). In order to confirm the detachment and blistering on the coating, the coated CS samples were analyzed by a salt spray in a 7.69 % NaCl solution, with an IT of 15 days. The obtained results showed that the CS surface state directly influenced the coating performance and the Ec parameter values variation, as a function of IT in the NaCl solution. EIS was the most valid Ec method for the studied coatings.