Browsing by Author "Nadjemi, B."

Now showing 1 - 4 of 4

Comparative study of biosorption of Cu+2, Ni+2, Cd+2, Zn+2 and Co+2 ions on the Pleurotus mutilus biomass
(Université M'hamed Bougara de Boumerdès, 2018) Madani, A.; Selatnia, A.; Chergui, A.; Yeddou, A.R.; Nadjemi, B.
In this study the biomass Pleurotus mutilus was used for the biosorption of Cu2+, Ni2+, Cd2+, Zn+2 and Co+2 ions. The effect of different parameters such as contact time, adsorbate concentration, pH of the medium and temperature were investigated. The sorption capacities were in the order of Cd2+ > Zn+2 > Co+2 >Cu2+ > Ni2+ . This order can be explained by their different values of affinities respectively. In order to prediction of the rate controlling step(external or internal mass transfer) , Boyd model was used in all case. Results showed that the external mass transfer is the rate controlling step. Different thermodynamic parameters such as enthalpy and entropy and change in standard free energy have also been evaluated and it has been found that the reaction was spontaneous and exothermic in nature. The Freundlich, Langmuir, Temkin and Dubinin-Raduskuvich adsorption models were used for the mathematical description of the biosorption equilibrium.
Kinetic and thermodynamic studies of methylene blue adsorption on sorghum stems
(ALJEST, 2020) Sifoun, Naima; Yeddou, A-R.; Nouri, L-H.; Chergui, A.; Nadjemi, B.
The Raw Sorghum stems have been studied as to adsorb Methylene Blue from aqueous solution by batch technique. The effects of different parameters such as adsorbent dose, initial pH, ionic strength, contacttime and dye initial concentration have been studied. To describe the adsorption kinetics, five models were applied. Kinetic parameters for each adsorption kinetic equation were calculated and discussed. The experimental isotherm data were analyzed using three models. The recovery of methylene blue adsorption has been exceeded 80%.The pseudo-second order kinetic model adequately describes the kinetic data with high determination coefficient (R2=0.99). Langmuir isotherm model fits better than Freundlich and Temkin models for all temperatures studied, and the maximum methylene blue uptake was observed as 27.67 mg/g at 313 K. The estimated values for ΔG°were -2.56, -3.31and -3.78 kJ/mole at 295, 303 and 313 K respectively. The enthalpy changes ΔH°and entropy ΔS°of adsorption were 17.19 kJ/mole and 67.24 J/mole.K, respectively.
Removal in batch mode experiment of Methylene Blue onto trimming Wood of Orange Tree –Equilibrium and Kinetics Studies –
(ALJEST, 2018) Sifoun, Naima; Abbas, Moussa; Yeddou, A. R.; Nouri, L.; Nadjemi, B.
In the present study, adsorption of Methylene Blue (MB) from aqueous solution was investigated using an adsorbent derived from Trimming Wood of Orange Tree (WOT). The used adsorbent was analyzed using FT-IR and SEM techniques.The adsorption of MB was carried out using a batch system and the effects of adsorbent dose, initial pH, ionic strength, contact time, initial concentration and temperature on the adsorption capacity of adsorbent were investigated. Kinetic parameters, rate constants, equilibrium adsorption capacities and determination coefficients, for each kinetic equation were calculated and discussed. It was shown that the adsorption of MB onto WOT could be described by the pseudo-second order kinetic. The experimental isotherm data were analyzed using the Langmuir, Freundlich and Temkin models. Adsorption of MB onto WOT followed the Langmuir isotherm for all temperatures studied and the maximum MB uptake was observed as 48.78 mg/g at 293 K. The evaluation of thermodynamics parameters such as the negative Gibbsfree energy and negative enthalpy change indicated respectively the spontaneous and exothermic nature of thesorptionprocess
Removal of methylene blue in aqueous solution by oxidation with hydrogen peroxide in presence of copper-impregnated activated alumina
(Aljest, 2019) Bousalah, Djedjiga; Yeddou, A. R.; Hachemi, M.; Nadjemi, B.
In this work, methylene blue in aqueous solution is removed by oxidation with hydrogen peroxide in the presence of copper impregnated activated alumina. After preparation and characterization of the catalyst, the catalytic oxidation tests are performed. The effects of pH, H2O2 concentration, catalyst dose, and temperature have been investigated. The tests show that adding activated alumina increases significatively the degradation effeciency of methylene blue. The reuse of catalyst for four cycls shows a good catalytic stability. The elevation of the temperature affects positively the kinetics of degradation. The acidified medium increases the decolorization efficiency of dye.