Publications Scientifiques
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Item Etude du potentiel d’utilisation des déchets agroalimentaires, les grignons d’olives et les noyaux de date pour récupération et adsorption des métaux lourds(Université M'Hamed Bougara Boumerdes, 2015) Babakhouya, N.; Boughrara, S.; Abed, F.; Abai, N.; Midoune, S.La présente étude porte sur l’application d’un adsorbant naturel préparé à base de grignon d’olives et de noyaux de dattes à différents pourcentages dans le domaine de traitement des effluents liquides industriels. Dans notre travail nous nous sommes intéressés à son application pour le cadmium (métal lourd). L’effet de plusieurs paramètres tel que le temps de contact, la concentration initiale en ions de cadmium, et le pH de la solution a été étudié en système en batch. Une modélisation des isothermes d’adsorption a été effectuée à l’aide des models d’isothermes de Langmuir, Freundlich et Temkin et leur coefficient de corrélation obtenus, indiquent que le model de Langmuir est favorable pour la plupart des proportions d’adsorbantsItem Copper, Zinc And Nickel’s Removal By Bentonite Clay: Case Study In Mono And Multicomponent Systems(Université M'Hamed Bougara Boumerdes, 2019) Hamdache, F.; Chergui, A.; Halet, Farid; Yeddou, A.R.The main purpose of this work is the Copper, Zinc and Nickel’s removal from mono and multi-metal ions aqueous solution using an Algerian bentonite without treatment. The bentonite is characterized using SEM, XRD and X-ray fluorescence. The effect of initial pH and contact time are studied. Under mono and multicomponent systems, the kinetic studies performed at pH 5, indicate that the adsorption follows a pseudo second order model. For both systems, the isotherm data are well correlated with Langmuir model. Whereas the maximum adsorption capacities follow the sequence’s order Cu > Zn > Ni. In the case of multicomponent system, the Cu(II), Zn(II) and Ni(II) adsorptions capacities (58.82, 19.53 and 6.56 mg/g) are lower than the obtained ones for the monocomponent system (58.48, 49.02 and 31.74 mg/g). In addition to that, a mutual competitive effect is observed. Zn(II) and Ni(II) ions adsorption is also inhibited by Cu(II) ions with no change in the maximum Cu(II) adsorption capacity.Item 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 Study of the adsorption of methylene blue by natural materials (olive stone, date pit and their mixture) in fixed bed column(ALJEST, 2019) Abed, Fatma; Aksa, H.; Abai, N.; Babakhouya, N.The present study focuses on the recovery of two agro-food waste available in our country with significant quantities olive pomace and date pits for the removal of a synthetic dye which is methylene blue. Both materials were used in their native forms separated and mixed to improve their adsorptive capacity. A range of physico-chemical analysis was performed to characterize adsorbents used, among them: the FTIR spectroscopy and the scanning electron microscopy. The ability of adsorbents prepared to adsorbe methylene blue (MB) from the aqueous solution was investigated in a fixed bed column. The effects of several important parameters were studied, such as initial concentration of MB, flow rate and bed height. The corresponding breakthrough curves were calculated.Item Oxygen diffusion and migration in clean and defective uranium nitride UN (0 0 1) surfaces(Elsevier, 2018) Zergoug, T.; Abaidia, Seddik-El-Hak; Nedjar, A.This study focuses on the diffusion of atomic and molecular oxygen through the uranium mono-nitride UN (0 0 1) surface. The adsorption of oxygen at the most favorable sites has been checked on different surface states namely: clean surface and surfaces containing defects such as inclusion atoms. Inclusions atoms are positioned at a uranium U atom vacancy or at a nitrogen N atom vacancy location of the UN (0 0 1) surface. Neptunium, plutonium, protactinium, silver and neodymium which are the most probable nuclear reactions (n, U) products have been selected as U atom substitute. Some light elements such as carbon, chromium and silicon were used to replace an N atom. The first principle calculation, based on Density Functional Theory (DFT) was used, taking into account the Generalized Gradient Approximation (GGA) and the Projector-Augmented Wave (PAW) to describe the exchange-correlation functional. The purpose of this work is to verify the oxygen adsorption energy variations performed across all the studied surfaces. The most favorable sites of UN (0 0 1) clean and defective surfaces to oxygen O atom diffusion were preliminary identified. In the second step, atomic dynamical Potential Energy Surface (PES) was used to study the interaction between O atom and UN (0 0 1) surfaces at these sites. Finally, Nudged Elastic Band (NEB) method was used in order to investigate the migration of O atom through the UN (0 0 1) surfaces. The results show that at the bridge site, the adsorption and incorporation energies of oxygen atom on and in the UN (0 0 1) surfaces respectively, do not substantially vary with the type and position of the studied impurities. But, at the N vacancy site, the adsorption energy of the O atom decreases practically when UN (0 0 1) surfaces contain inclusion atoms compared to the clean surface case. Furthermore, the NEB calculations show discrepancies for the Minimum Energy Path (MEP) during the migration of the O atom at the bridge site through the studied UN (0 0 1) surfaces and depending on the type and position of the added impurities. Among the studied MEPs, protactinium is found to be the most suitable barrier to the diffusion of oxygen through the UN surface as an inclusion on UN (0 0 1)Item Etude potentielle de mélange des adsorbants naturels (grignons d’olive et noyaux de dattes) pour l’adsorption du chrome(Aljest, 2016) Aksas, Hammouche; Cherifi-Nacy, H.; Babaci, N.; Louhab, K.Cette étude a pour objectif d’étudier le potentiel d’utilisation de matériaux naturels (mélange homogène de noyaux de dattes et de grignons d’olives) issus de l’activité d’agriculture pour le traitement des eaux usées, chargées en polluant métallique: le chrome. Ces deux matériaux ont été activés chimiquement par l’acide phosphorique, en les mélangeant à différents pourcentages, afin d’obtenir une solution solide homogène et d’améliorer leur capacité adsorptive. L’adsorption des ions du chrome est étudiée en milieu dispersé (batch) à la fois sur les matériaux pur et à l’état du mélange à différentes proportions, composées d’une quantité fixe en noyaux de dattes (ND), et des quantités du grignon d’olive (GO) variées. Les résultats d’adsorption du chrome montrent : qu’elle est maximale à un pH =5.6, croit avec la température et avec la concentration initiale du chrome dans la solution. Le modèle de Langmuir stimule mieux les isothermes d’adsorption du chrome que d’autres modèles étudiés (avec un coefficient de corrélation de 0.9988 pour (88% NDI, 12% GOI). L’adsorption du chrome augmente avec l’augmentation du taux du grignon d’olive dans le mélange d’adsorbant (grignon d’olive et noyau de date).Item Feasibility study of adsorption of a textile dye on activated carbon prepared starting from the coffee grounds(Aljest, 2017) Mahdi, K.; Benrachedi, K.The activated carbon used in this study is prepared starting from the coffee ground whose abundance is important in our country and of which the use is often limited to food consummation. The physical characterization (porosity and surface) was determined by the adsorption of gas nitrogen to 77 K (BET), showed the presence of macropores (1.77 m2 /g), as well as the analysis by electronic scan microscopy MEB revealed the presence of a broad specific surface. The activated carbon obtained starting from the coffee ground was the object of an application to the aqueous medium for tests of elimination of a cation dye (methylene blue) used in the industry of textile, prepared synthetically. Several parameters were studied in order to optimize the ideal conditions for a good adsorption of the pollutant to study; in particular, the kinetics of adsorption, the effect of the initial concentration and the effect of the pH of the solution examined. The simulated isotherms of adsorption are very correctly described by the models of Langmuir and Freundlich. The percentage of discolouration reached is of: 99%. Therefore, one can conclude that this study showed that the coffee ground chemically activated can be used like new adsorbent for the water treatment contaminated by the textile dyesItem Etude de l’adsorption des composés phénoliques sur des membranes polymères à base de poly (vinyl alcool) /β-cyclodextrine(Aljest, 2018) Ghemati, D.; Aliouche, D.L’objectif principal de ce travail est l’étude de d’adsorption des polluants aromatiques: 2- chlorophénol, 2-nitrophenol sur des membranes à base des polymères polyvinylalcool modifiées par la cyclodextrine. Pour cela des membranes à base de polyvinylalcool réticule avec le glutaraldehyde (PVA/GA) ont été préparés, puis l’incorporation de la β-Cyclodextrine dans ces membranes ((PVA / GA / β-CD) à différentes compositions (2, 4, 6, 8% β-CD) a été réalisé. La synthèse a été confirmée par analyse spectroscopique infra rouge (FTIR). Et le comportement du gonflement des membranes a été étudié. Enfin, Les expériences d’adsorption des composés phénoliques ont été réalisées dans des solutions aqueuses. Les résultats d’adsorption à différent pH indiquent que le maximum de la capacité d’adsorption est obtenu à pHItem Study of the adsorption of methylene blue by natural materials (olive stone, date pit and their mixture) in fixed bed column(Aljest, 2019) Abed, F.; Louhab, K.; Abai, Nadjet; Babakhouya, N.The present study focuses on the recovery of two agro-food waste available in our country with significant quantities olive pomace and date pits for the removal of a synthetic dye which is methylene blue. Both materials were used in their native forms separated and mixed to improve their adsorptive capacity. A range of physico-chemical analysis was performed to characterize adsorbents used, among them: the FTIR spectroscopy and the scanning electron microscopy. The ability of adsorbents prepared to adsorbe methylene blue (MB) from the aqueous solution was investigated in a fixed bed column. The effects of several important parameters were studied, such as initial concentration of MB, flow rate and bed height. The corresponding breakthrough curves were calculatedItem Kinetic and equilibrium studies of salicylic acid adsorption from contaminated water by (alginate/chitosan/cobalt ferrite) nanocomposites(Aljest, 2019) Aroun, I.; Bensacia, N.; Seffah, K.; Benyahia, S.The main objective of this study is the synthesis of the (Alginate / Chitosan/ Cobalt ferrite) nanocomposites. The asdsorbent was characterized via Fourrier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (DRX) and zeta potential. The adsorption tests of salicylic acid on the (Alginate / chitosan / cobalt ferrite) adsorbent were carried out at a temperature of 25°C, pH equal to 4, a mass of 10 mg and a concentration of 10 mg /L. Under these conditions, the adsorption capacity was found to be of the order of 10 mg /g, which corresponds to an equilibrium time of 90 min. The kinetics of adsorption is correctly written by the kinetic model of the pseudo second order. The adsorption data were fitted using the Langmuir and Freundlich isotherms, and the obtained modeling equilibrium adsorption data suggested that the (Alginate / Chitosan/ Cobalt ferrite) nanocomposites sample contained homogeneous adsorption sites that fit the Langmuir adsorption model well