Publications Scientifiques
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Item Adsorption of heavy metals (Cd, Zn and Pb) from water using keratin powder prepared from Algerien sheep hoofs(European Journals Inc, 2009) Souag, Rafika; Touaibia, D.; Benayada, B.; Boucenna, A.Item Chromium (VI) adsorption onto activated kraft lignin produced from alfa grass (Stipa tenacissima)(2009) Tazrouti, N.; Amrani, MoussaActivated lignin having a surface area of 1023 m 2 g -1 has been prepared from sulfate lignin that was treated by 30% H 2O 2 and carbonized at 300 oC in order to test the chromium (VI) adsorption from aqueous solution. The influence of contact time, pH, initial concentrations of adsorbent and adsorbate, and temperature on the adsorption capacity were investigated. The maximum removal of Cr(VI) was found to be 92.36 % at pH=2 and a contact time of 80 min. Optimal concentration of lignin and Cr(VI) were found to be 3.8 g L -1 and 180 mg L -1, respectively. The adsorption kinetics data fitted well with a pseudo-second-order equation, and the rate of removal of chromium was found to speed up with increasing temperature. Activation energy for the adsorption process was found to be 18.19 kJ mol -1. The Langmuir and Freundlich adsorption isotherm models were applied to describe the isotherm and isotherm constants for the adsorption of Cr (VI) on lignin. These constants and correlation coefficients of the isotherm models were calculated and compared. Results indicated that Cr (VI) uptake could be described by the Langmuir adsorption model. The maximum adsorption capacity (q m) of Cr (VI) on lignin was 75.75 mg g -1 at 40°C. The dimensionless equilibrium parameter (R L) signified a favorable adsorption of Cr (VI) on lignin and was found to be between 0.0601 and 0.818 (0Item Valorisation du marc de café dans le domaine du traitement des effluents liquides = Valorisation of coffee grounds : Processing of liquid effluents(2001) Benrachedi, k.; Mekarzia, A.; Messaoud-Boureghda, M. Z.Le but du présent travail consiste en une mise en oeuvre des propriétés dépolluantes en milieu aqueux d'un marc de café transformé en charbon actif. En vue d'étudier les implications pratiques de ce nouveau matériau activé, nous avons étudié l'adsorption du phénol à partir de solutions synthétiques en tant que modèles de pollution. Le marc de café est activé chimiquement et thermiquement pour modifier sa structure, la nature de ses sites et leurs répartitions à la surface de ce charbon, ce qui a permis d'améliorer sa capacité d'adsorption. La vitesse d'adsorption du phénol sur le marc de café activé a été étudiée en fonction de plusieurs paramètres physico-chimiques: la température, la concentration initiale en phénol et des conditions hydrodynamiques telles que la vitesse d'agitation. Les paramètres de l'équilibre de l'adsorption obtenus d'après l'équation de Langmuir: c'est à dire la capacité ultime d'adsorption G. et la constante K du pseudo-équilibre de l'adsorption, ont été déterminés. Les résultats expérimentaux obtenus montrent que le marc de café activé présente des caractéristiques similaires d'adsorption à celles aux produits existants sur le marché commercial et confirme parfaitement l'applicabilité du marc de café activé dans le traitement des eaux uséesItem Thermodynamic of chromium sorption on biomass fungi from aqueous solution(2006) Louhab, K.; Addad, J.; Barr, S.; Goma, B.The thermodynamics of chromium ions sorption from aqueous solution on biomass fungi have been investigated. The experimental data was analysed by Langmiur and Scatchard isotherms. The equilibrium sorption capacity of chromium ions was determined from Langmiur and Scatchard equation at different temperature. Bad correlation coefficients were obtained for the Langmiur adsorption equilibrium constant. Various thermodynamics parameters, Δ H°ads, Δ S°ads and equilibrium constant values were computed at different temperature. The results show that the sorption of the chromium ions on biomass fungi is spontaneous and exothermic nature process, the thermodynamics parameters are dependent of the temperature and the equilibrium sorption capacityItem Identification of parameters W0 , n , and D of the Dubinin�Radushkevich equation(2003) Nour, Abdelkader; Tazerouti, H.; Ouragh, Y.This paper considers a cooling system for a thermal engine using heat from exhaust gas. This system uses a physical adsorption process of solid�gas (active carbon and ammonia). An adsorber tubular element of real scale is submitted to heat flux by electrical air heating, simulating exhaust gas. Temperatures and adsorbed mass are measured. Desorption and adsorption phenomena are described by the Dubinin�Radushkevich model equation, m = W0 [rgr] ( T ) exp[- D ( T? ln ( Ps ( T )/ P )) n ], where W0 , n , and D are parameters characterising the adsorbent�adsorbate couple. These three parameters can be identified from a simple mite method (using data and models) characterising the adsorbent�adsorbate couple chosenItem Effect of calcium competition on chromium adsorption by fungi biomass(2006) Louhab, K.; Sahmoune, Mohamed Nasser; Addad, J.; Bar, S.The kinetics and thermodynamic of adsorption of a mono-solute of chromium ions and of a bi-solute of chromium and calcium ions by fungi biomass (Streptomycine rimosus) was investigated in a batch system. The experimental data were analyzed based by Langmuir isotherm and a Pseudo second order mechanism, in the both the mono-and bi-solute adsorption systems, in order to predict the rate constant of adsorption, the equilibrium capacity. The results indicate that the adsorption mechanism is described by Langmuir isotherm and a Pseudo-second-order. The equilibrium adsorption capacity and the equilibrium rate constant increased with an increase in the initial chromium concentration in both mono-and bi-solute adsorption systems. The adsorption capacity of chromium decreased with an increase in calcium concentrationItem Determination of the adsorption capacity of activated carbon made from coffee grounds by chemical activation with ZnCl2 and H3PO4(2005) Namane, A.; Mekarzia, A.; Benrachedi, K.; Belhaneche-Bensemra, Naima; Hellal, A.In order to evaluate the adsorptive capacities of granular activated carbon produced from coffee grounds by chemical activation, the adsorption of different phenols and acid and basic dyes, has been carried out. The comparison with a commercial activated carbon has been made. Adsorption isotherms of phenols and dyes (acid and basic) onto produced and commercial granular activated carbons were experimentally determined by batch tests. Both Freundlich [1] and Langmuir [2] models are well suited to fit the adsorption isotherm data. As a result, the coffee grounds based activated carbon may be promising for phenol and dye removal from aqueous streams