Publications Internationales

Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13

Browse

Search Results

Now showing 1 - 7 of 7
  • Item
    Experimental and modelling study of adsorption and diffusion of hexavalent chromium in zeolitic imidazolate framework-11
    (Taylor and Francis, 2025) Lamari, Rachid; Benotmane, Bénamar; Megherbi, Hamza; Brahmi, Aghilas; Djaoui, Souad; Trari, Mohamed
    In this study, Zeolitic Imidazolate Framework-11 (ZIF-11) was successfully synthesised at room temperature and characterised by XRD, SEM/EDAX, TGA/DSC, FTIR, and CO₂ adsorption techniques. The material exhibited high crystallinity, well-defined morphology, a thermal stability up to 350 °C, low synthesis cost, and the possibility of scaling up production. Motivated by these favourable properties, ZIF-11 was investigated as an adsorbent for the removal of (Formula presented.) from aqueous solutions. Optimal adsorption conditions were found to be a pH 2, a stirring speed of 400 rpm, a contact time of 70 min and a 20 mg dose of ZIF-11 for 50 mL of (Formula presented.) solution. Thermodynamic studies indicated that the adsorption process is spontaneous and endothermic. Kinetic analysis showed that the adsorption follows the pseudo-second-order model, suggesting chemisorption as the dominant mechanism. Isotherm modelling using Langmuir and Freundlich equations confirmed a uniform distribution of (Formula presented.) species on the ZIF-11 surface. The maximum adsorption capacity of ZIF-11 was found to be 10.61 mg/g, surpassing many reported adsorbents. These findings demonstrate that ZIF-11 is a highly promising material for the (Formula presented.) removal from water. Its excellent adsorption capacity, thermal stability, and ease of synthesis highlight its potential for practical applications in water treatment and environmental remediation.
  • Item
    Engineering of Natural Clay-Based Materials to Eliminate Toxic Pb(II): Kinetic, Thermodynamic, and Adsorption Mechanism
    (PHYSICOCHEMICAL PROCESSES AT THE INTERFACES Published, 2025) Abbas, Moussa; Trari, Mohamed
    Climate change poses a threat to the water security by altering the precipitation patterns and other weather variables, which affect stream flow and freshwater availability. In this study, a soil and water assessment tool was used for the scarcity of blue and green water for future periods for sustainable management of freshwater resources away from lead pollution. Indeed, the presence of Pb2+ is an environmental problem and we have explored the use of natural phosphates (NP) as adsorbents for its elimination. The adsorbent NP was characterized by FTIR spectroscopy, scanning electron microscopy (SEM) and BET analysis. Batch adsorption experiments were performed to examine the effects of physical parameters namely the contact time, pH, stirring speed, temperature, adsorbent dose and initial Pb2+ concentration on the uptake capacity. Different models were used to fit the experimental data and to evaluate the kinetics, isotherms and thermodynamics of the Pb2+ adsorption. A high adsorption capacity of 66.66 mg/g was reached at 25°C and pH 6 and follows the Langmuir isotherm with a pseudo-second order kinetic. The adsorption is spontaneous and endothermic, indicating a structural exchange between NP and Pb2+ ions. Such results suggest that NP is a promising adsorbent for Pb2+ removal from wastewater
  • Item
    Adsorption Behavior of Methylene Blue Onto Activated Coconut Shells: Kinetic, Thermodynamic, Mechanism and Regeneration of the Adsorbent
    (SAGE, 2024) Abbas, Moussa; Trari, Mohamed
    Adsorption 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
    Elaboration of a new Activated Carbon derived from the Crown of Oak (ACOW) to removal the toxic Iodine: Kinetic, Isotherms modelling and Thermodynamics Study
    (Taylor & Francis, 2024) Aksil, Tounsia; Abbas, Moussa; Trari, Mohamed
    The current study aims to develop a new adsorbent material using oak crown and explore its effectiveness in removing I2 ions through a series of batch experiments. ACOW was characterised by zero charge (pHpzc) and FTIR spectroscopy. The impact of the initial I2 concentration (20-100 mg/L), temperature (25-55 °C), pH (2-14), adsorbent dosage (2-10 g/L), Stirring speed (100-900 rpm), particle size (100-2000μm) and contact time (0-30 min) on I2 adsorption was examined. The adsorption kinetic obeys the pseudo-second order model with a determination coefficient (R2) equal to 0.999. Adsorption follows the Langmuir equation well, with the best fit to the experimental data at equilibrium. A qmax value (= 103.606 mg/g) at 25°C and 120.773 mg/g at 55°C were eliminated under the optimised conditions, indicating homogeneous adsorption on the surface of the adsorbent. The thermodynamic parameters gave a negative free energy ΔGo (-3.445 to -5.629 kJ/mol), a positive enthalpy ΔHo (18.406 kJ/mol) and an activation energy Ea (= 22.599 kJ/mol), thus confirming the spontaneous and endothermic nature of adsorption of iodine on ACOW. The positive entropy ΔSo (0.0733 kJ/mol K) show increased randomness of the solid-liquid interface during the adsorption.
  • Item
    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, Mohamed
    The 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 endothermic
  • Item
    Removal of toxic methyl green (Mg) in aqueous solutions by apricot stone activated carbon – equilibrium and isotherms modeling
    (Taylor & Francis, 2018) Abbas, Moussa; Aksil, Tounsia; Trari, Mohamed
    Apricot stone activated carbon (ASAC), was powdered, activated and to be used as effective adsor-bent to remove the dyes from aqueous solutions through batch experiments under operational factors namely, pH, contact time, adsorbent dose, initial dyes concentration and temperature. The physico-chemical, morphological and structural properties of the adsorbents were characterized by scan-ning electron microscope (SEM) and X-ray diffraction (XRD) instruments. Different kinetic modelsindicated that the adsorption is well described by the pseudo-second order model. The isotherms of methyl green (MG) adsorption on ASAC were obtained and correlated with various models. The smaller RMSE values for the Langmuir and Dubinin-Radushkevic models indicated the best fitting; the mono layer adsorption capacity of MG was found to be 148.478 mg g–1 at 21°C and 88.11 mg g–1 at 46°C at pH 10. The thermodynamic functions showed spontaneous and endothermic MG adsorption. In conclusion, the adsorbent prepared from apricot stone (ASAC) was found to very effective and suitable adsorbent for reactive dyes removal from aquatic environment, due to its simple and cheap preparation, easy availability and good adsorption capacity.