Publications Internationales
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Item Adsorption Behavior of Methylene Blue Onto Activated Coconut Shells: Kinetic, Thermodynamic, Mechanism and Regeneration of the Adsorbent(SAGE, 2024) Abbas, Moussa; Trari, MohamedAdsorption techniques are widely used to remove some classes of pollutants from waters, especially those which are not easily biodegradable. The removal of Methylene blue (MB), as a pollutant, from waste waters of textile, paper, printing and other industries has been addressed by the researchers. The aim of this study is to eliminate MB by Activated Coconut Shells (ACS) produced at low cost by adsorption in batch mode. The ACS was characterized by the FTIR spectroscopy and point of zero charge (pHpzc: 5.06). Some examined factors were found to have significant impacts on the MB uptake of ACS like the initial dye concentration Co (40-120 mg/L), solution pH (2-8), ACS dose (1-12 g/L), agitation speed (50-500 r/min), particles size (1.0- 1.2 mm) and temperature (298-333 K). The best capacity was found at pH 6 with an adsorbent dose 8 g/L, an agitation speed 200 r/min and a contact time of 60 min. Modeling Kinetics and Isotherms shows that the pseudo-second-order kinetic model with R2 (0.935 -0.998) and Langmuir adsorption isotherm model provide better fitness to the experimental data with the maximum adsorption capacity of 30.30 mg/g at 25°C. The separation factor R L (0.933-0.541) in the concentration range studied (10-120 mg/L) shows a favorable adsorption. The isotherms at different temperatures have been used for the determination of the free energy ΔG ° (198-9.72 kJ/mol); enthalpy ΔH ° (82.082 kJ/mol) and entropy ΔS o (245.689 J/K mol) to predict the nature of MB adsorption process. The positive values of (ΔG o ) and (ΔHo ) indicate a non-spontaneous and endothermic MB adsorption with a chemisorption. The adsorbent elaborated from Coconut Shells was found to efficient and suitable for the removal of MB dye from aqueous solutions, due to its availability, low cost preparation and good uptake capacity.Item Removal of Amoxicillin From Wastewater Onto Activated Carbon: Optimization of Analytical Parameters by Response Surface Methodology(SAGE Publications Inc., 2024) Abbas, Moussa; Trari, MohamedAntibiotics are widely used in veterinary and human medicine, but these compounds, when released into the aquatic environment, present potential risks to living organisms. In the present study, the activated carbon (AC) used for their removals is characterized by FT-IR spectroscopy, BET analysis and Scanning Electron Microscopy (SEM) to determine the physicochemical characteristics. Response surface methodology (RSM) and Box-Behnken statistical design (BBD) were used to optimize important parameters including pH (2-12), temperature (20-45°C), and AC dose (0.05-0.20 g). The experimental data were analyzed by analysis of variance (ANOVA) and fitted to second-order polynomial using multiple regression analysis. The optimal conditions for maximum elimination of Amoxicillin (Amox) are (Dose: 0.124 g, pH 5.03 and 45°C) by applying the desirability function (df). A confirmation experiment was carried out to evaluate the accuracy of the optimization model and maximum removal efficiency (R = 89.999%) was obtained under the optimized conditions. Several error analysis equations were used to measure goodness of fit. Pareto analysis suggests the importance of the relative order of factors: pH > Temperature > AC dose in optimized situations. The equilibrium adsorption data of Amox on Activated Carbone were analyzed by Freundlich, Elovich, Temkin and Langmuir models. The latter gave the best correlation with qmax capacities of 142.85 mg/g (R2 = 0.999) at 25°C is removed from solution. The adsorption process is dominated by chemisorption and the kinetic model obeys a pseudo-second order model (R2 = 0.999).Item Direct Drive Permanent Magnet Synchronous Generator: Design, Modeling, and Control for Wind Energy Applications(2024) Larabi, Zina; Ghedamsi, Kaci; Aouzellag, DjamalThe prominent trend in wind turbine technology centers on the adoption of direct-drive permanent magnet synchronous generators (DD-PMSG), a choice driven by their capacity to deliver superior efficiency through the elimination of gearboxes.This paper presents a comprehensive exploration of the design, modeling, and control aspects of a DD-PMSG intended for harnessing wind energy conversion. Initially, the geometrical design of the generator is meticulously carried out, adhering to predefined technical specifications and constraints. Subsequently, an in-depth internal modeling, focusing on the electromagnetic behavior of the designed generator, is executed using finite element analysis (FEA) through the Ansys Maxwell RMXpert software. Finally, the external modeling and control system integration of the designed generator, connected to the grid through power electronic converters, are simulated using the Matlab/Simulink software suite. The resulting findings underscore the efficacy and viability of the proposed generator for wind turbine applications, affirming its potential to enhance wind energy conversion systemsItem An Analytical Approach for Evaluating Turn-On Switching Losses in SiC MOSFET With Kelvin Pin: Concept and Implementation(Institute of Electrical and Electronics Engineers Inc, 2024) Mohammed Cherif, okba; Nadji, Bouchra; Tadjer, Sid Ahmed; Bencherif, HichemWith the progressive adoption of silicon carbide (SiC) power devices in modern power converters, exploiting their superior efficiency, faster switching speed, and higher power density, an understanding of the factors influencing these properties becomes vital. One such critical factor is switching losses, which can drastically affect overall system performance. This study develops and presents a new analytical model for predicting the turn-on switching losses in SiC MOSFETs with Kelvin pin. The proposed model, derived from a carefully constructed set of nonlinear differential equations, accounts for the nonlinearity of the transconductance by incorporating a novel transfer characteristic model. The model also incorporates the nonlinear junction capacitances effects. The developed analytical model allows for the prediction and optimization of turn-on switching losses in SiC MOSFETs, thus enabling improved energy efficiency and reliability. The accuracy of the proposed model is verified through comparison with experimental results obtained using the double pulse test board that was designed and constructed, demonstrating its applicability for the investigation of SiC MOSFET power lossesItem Technical-economic study of PVC-based formulations intended to industrial 3-wire electric cables, using a full factorial design methodology(2023) Cherfi, Abdelhamid; Dehak-Oughlissi, Karima; Ben Meddour, TouhamiIn the present study, full factorial designs were used to model and optimize the mechanical properties of PVC-based formulations constituting three-core power cables: sheathing, insulation and stuffing, while respecting the standards in force, and aiming for a minimum cost. The effects of 4 parameters: plasticizer content (X1), filler content (X2), stabilizing agent content (X3) and the kind of plasticizer were investigated on the following properties: Density (D), Hardness (H), Elongation at break (EB) and Fracture resistance (FR), as well as the price (DA/kg of formulation). The desirability-based optimization gave the following values: EB = 214.72%, FR = 19.94 MPa and Price = 116.71 DA/kg for the sheathing; EB = 198.11%, FR = 4.38 MPa and Price = 61.73 DA/kg for the stuffing; EB = 207.84%, FR = 19.35 MPa and Price = 102.73 DA/kg for the insulation. The study revealed also that the order of significance of the effects on the mechanical properties was: X1>X2>X3 and that the use of cheapest plasticizer did not affect greatly the mechanical propertiesItem Adsorption of malachite green onto walnut shells : kinetics, thermodynamic, and regeneration of the adsorbent by chemical process(Korean Fiber Society, 2023) Merrad, Samiya; Abbas, Moussa; Trari, MohamedThe textile industry produces huge amounts of wastewaters containing synthetic and toxic dyes. The aim of this study was to evaluate the adsorption of Malachite green (MG) onto Activated Carbon from Walnut Shells (ACWS) realized in a batch system. The effects of contact time, initial pH, stirring speed, particle size, temperature, adsorbent dose, and initial MG concentration on the adsorption capacity were investigated graphically for determining optimum conditions. The experimental isotherm data were analyzed by the Langmuir, Freundlich, Temkin, and Elovich models. The adsorption follows well the Langmuir equation, providing a better fit of the equilibrium adsorption data. Under optimized conditions, up to 154.56 mg/g at 25 °C and 370.37 mg/g at 45 °C were removed from the solution. The adsorption mechanism of MG onto ACWS was studied using the first-pseudo-order, second-pseudo-order, Elovich and Webber–Morris diffusion models. The adsorptions’ kinetic was found to follow rather a pseudo-second-order kinetic with a determination coefficient (R2) of 0.999. The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters, i.e., the free energy ΔGo (0.802 to − 2.123 kJ/mol), positive enthalpy change ΔHo(18.547 kJ/mol), entropy (ΔSo = 0.064 kJ/molK), and activation energy (Ea = 14.813 kJ/mol). The negative ΔGo and positive ΔHo values indicate that the overall MG adsorption is spontaneous and endothermicItem Potential of titanium dioxide to remove bromothymol blue (BTB) in aqueous solution by batch mode Adsorption–Kinetic, isotherm and thermodynamic studies(Springer, 2023) Abbas, MoussaThe adsorption is widely used to remove certain classes of pollutants from water, especially those that are hardly biodegradable and dyes represent one of these problematic groups. The removal of bromothymol blue (BTB) from wastewater using TiO2 was studied in batch system. The adsorbent TiO2 has a specific surface area of 400 m2/g, a mean crystallites sizes (5–10 nm), and pHpzc equal to 6.5. TiO2 is stable over the whole pH range and constitutes a good compromise between efficiency and stability (in both acidic and basic media), therefore, the use of other additives is not necessary. Its non-toxicity and low energy required for its activation (E ~ 3 eV) as well as its low cost for most of the applications envisaged make it advantageous. The influence of effective variables such as solution pH (1–10), contact time (0–60 min), initial BTB concentration (5–40 mg/l), adsorbent dose of TiO2 (0.2–2 g/l), and temperature (20–60 °C) on the adsorption efficiency was examined, while the BTB content was determined by UV–Vis spectrophotometry. The optimal pH, adsorbent dose, and contact time for the efficient removal were found to be 10, 0.2 g/l, and 30 min, respectively, and the adsorbent was characterized by the BET analysis and point of zero charge (pHpzc). Among the different kinetic models, the experimental data of the BTB removal are well fitted with the pseudo-first-order kinetic model with a high determination coefficient. The evaluation of the fitness of equilibrium data by various conventional isotherm models, based on the R2 value as criterion, show the successful applicability of the Langmuir model for the interpretation of experimental data with a maximum adsorption capacity (qmax) of 27.02 mg/g at 20 °C and R2 of 0.997. The adsorption isotherms at different temperatures have been used for the determination of the free energy (ΔGo = 2.1808 to—1.0981 kJ/mol), enthalpy (ΔHo = 20.74 kJ/mol), and entropy (ΔSo = 65.58 J/mol/K) indicate that the overall adsorption is spontaneous and endothermic in natureItem Thermodynamic and kinetics studies on adsorption of Indigo Carmine from aqueous solution by activated carbon(Elsevier, 2019) Harrache, Zahia; Abbas, Moussa; Aksil, Tounsia; Trarib, MohamedThe kinetic and equilibrium parameters of the quantitative adsorption for Indigo Carmine (IC) removed by commercial activated carbon (AC) were studied by UV–visible absorption spectroscopy. AC with a high specific surface area (1250.320 m2/g) was characterized by the Brunauer–Emmett–Teller (BET) method and point of zero charge (pzc). The effect of the initial dye concentration (10–60 mg/L), contact time (0–90 min), pH (1−12), agitation speed (0–600 rpm), adsorbent dose (1–10 g/L) and temperature (298–323 K) were determined to find the optimal conditions for a maximum adsorption. The adsorption mechanism of Indigo Carmine onto AC was studied using the first pseudo order, second pseudo order and Elovich kinetics models. The adsorptions kinetic were found to follow a pseudo second order kinetic model with a determination coefficient (R2) of 0.999. To get an idea on the adsorption mechanism, we applied the Webber-Morris diffusion model. The equilibrium adsorption data for Indigo Carmine on AC were analyzed by the Langmuir, Freundlich, Elovich, Dubinin and Temkin models. The results indicate that the Langmuir model provides the best correlation at 25 °C (qmax = 79.49 mg/g) and Dubinin at 40 °C (qmax = 298.34 mg/g). The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters such as free energy (ΔG° = −0.071 to −1.050 kJ/mol), enthalpy (ΔH° = 28.11 kJ/mol), entropy (ΔS° = 0.093 kJ/mol·K) and activation energy (Ea) of 51.06 kJ/mol of adsorption. The negative ΔG° and positive ΔH° values indicate that the overall adsorption is spontaneous and endothermic.Item Robust smart schemes for modeling carbon dioxide uptake in metal - organic frameworks(Elsevier, 2021) Nait Amar, Menad; Ouaer, Hocine; Abdelfetah Ghriga, MohammedThe emission of greenhouse gases such as carbon dioxide (CO2) is considered the most acute issue of the 21st century around the globe. Due to this fact, significant efforts have been made to develop rigorous techniques for reducing the amount of CO2 in the atmosphere. Adsorption of CO2 in metal–organic frameworks (MOFs) is one of the efficient technologies for mitigating the high levels of emitted CO2. The main aim of this study is to examine the aptitudes of four advanced intelligent models, including multilayer perceptron (MLP) optimized with Levenberg-Marquardt (MLP-LMA) and Bayesian Regularization (MLP-BR), extreme learning machine (ELM), and genetic programming (GP) in predicting CO2 uptake in MOFs. A sufficiently widespread source of data was used from literature, including more than 500 measurements of CO2 uptake in13 MOFs with various pressures at two temperature values. The results showed that the implemented intelligent paradigms provide accurate estimations of CO2 uptake in MOFs. Besides, error analyses and comparison of the prediction performance revealed that the MLP-LMA model outperformed the other intelligent models and the prior paradigms in the literature. Moreover, the MLP-LMA model yielded an overall coefficient of determination (R2) of 0.9998 and average absolute relative deviation (AARD) of 0.9205%. Finally, the trend analysis confirmed the high integrity of the MLP-LMA model in prognosticating CO2 uptake in MOFs, and its predictions overlapped perfectly the measured values with changes in pressure and temperatureItem Adsorption of methyl green (MG) in aqueous solution by titanium dioxide (TiO2) : kinetics and thermodynamic study(Springer, 2021) Abbas, MoussaAdsorption techniques are widely used to remove certain classes of pollutants from waters, especially those that are not easily biodegradable. In this respect, the removal of Methyl green (MG) from waste water using TiO2 was studied in batch system. This research was carried out to evaluate the capability of TiO2 toward the water treatment relevant to organic MG at batch conditions. The effects of contact time (0–60 min), initial pH (3–11), agitation speed (100–500 rpm), temperature (25–45 °C), adsorbent dosage (0.02–6 g/L), and MG concentration (50–200 mg/L) on the MG adsorption by TiO2 have been studied. The adsorption kinetics in view of four kinetic models, i.e., the pseudo-first-order Lagergren, pseudo-second-order, intra-particle diffusion and Elovich models, was discussed. The adsorption of MG is well described by the pseudo-second-order equation with the best determination coefficient (R2 = 0.999). The experimental isotherm data were analyzed by different models; the adsorption follows the Langmuir and Temkin models, providing a better fit of the equilibrium data. The batch adsorption experiments were carried out to optimize the physical parameters on the MG removal efficiency, and it has been found that 384.615 mg/g at 25 °C is removed. The positive value of the activation energy (Ea = 14.1813 kJ/mol) indicates the endothermic nature and clearly that the randomness is increased at the solid–solution interface during the MG adsorption onto TiO2, indicating that some structural exchange occurs among the active sites of the adsorbent and the MG species