A continuous adsorption study in a fixed-bed column was carried out using granulated slag (GS) as an adsorbent for the removal of methylene blue (MB) from aqueous solution. The effects of various parameters, such as initial dye concentration, flow rate, bed depth, and pH were investigated.Obtained results confirmed that the breakthrough time and exhaustion time were dependent on these factors. The adsorption capacity of GS was calculated at the 50% breakthrough point for different conditions. The highest breakthrough capacity (q ,exp ¼ 0.296 mg.g -1 ) was obtained with a 15 cm bed height and a 2 mL.min -1 rate by using a 10 mg.L -1 initial MB concentration at pH 7.5. Bohart-Adams, Bed Depth Service Time (BDST), and Thomas models were applied to experimental data to determine the characteristic parameters of the column. The Thomas model was found suitable for the description of the whole breakthrough curve, while the Bohart-Adams model was only used to predict the initial part of the dynamic process. The data were in good agreement with the BDST model. Thus, the granulated slag can be used as an adsorbent in the treatment of wastewater. Desorption was carried out with a deionized water as the desorbing agent, and reuse study was investigated.

A B S T R A C TThe objective of this study was the use of raw and modified coke material for the adsorption of cyanide ions (CN − ) in water. The surface functions of this material (carboxyl, lactones, phenol, and carbonyl) were modified by oxidation with sulfuric acid, nitric acid, and KMnO 4 solution at varying concentrations. This chemical surface treatment improved the adsorption capacity. The experimental results of adsorbent/adsorbate equilibrium show that the adsorption isotherms follow the Freundlich model and the kinetic adsorption follows the pseudo-second-order model. Overall, coke material oxidized by KMnO 4 has shown the best adsorption of CN − ions with an adsorption capacity q e = 1.28 mg g −1 at T = 20˚C and pH 11.

Cette contribution explore les différents linéaments de l’architecture des grands ensembles urbains modernes constitués pendant la période coloniale française (1830-1962). Cette période a charrié avec elle des nouveaux modèles urbanistiques et d’interventions qui ont marqué le paysage et les vécus urbains. De même, les politiques publiques et les grands projets, après l’indépendance, ont fait la part belle aux programmes d’habitat collectif dans les périphéries des villes, notamment dans l’agglomération oranaise, terrain de notre recherche. Aujourd’hui, les pouvoirs publics, conscients de la validité des critiques émises à l’encontre des réalisations précédentes, tentent de chercher des solutions dont les référentiels, cependant, ne sont pas éloignés de ceux des concepteurs des grands ensembles modernes de la période coloniale.

a b s t r a c tThe purpose of this work was to remove methylene blue (MB) from water using natural eggshell membrane (ESM) in fixed-bed column. The ESM was treated and characterized by Fourier transform infrared spectra (FTIR), scanning electron microscope (SEM) and X-ray diffraction (XRD). A series of experiments were carried out to investigate the effects of bed height on breakthrough curve, flow rate, MB concentration, solution pH (2-10), the ionic strength and temperature on the adsorption behavior. The experimental results show that the adsorption capacity increases with the increase in the bed depth and MB concentration. However, it decreases with increasing the flow rate and temperature. The ESM adsorption capacity of MB is more pronounced in basic medium. The addition of NaCl salt ions decreases the fixation of MB on ESM. Five kinetic models, Bohart-Adams, Wolborska, Thomas, Yoon-Nelson and bed depth service time (BDST) models were applied to experimental data in order to predict the breakthrough curves using non-linear regression and to determine the characteristic parameters of the column useful for process design. The results showed that Thomas and Yoon-Nelson models were found suitable for the normal description of breakthrough curve at the experimental condition, while Adams-Bohart and Wolborska models were only for an initial part of dynamic behavior of the ESM column. Desorption of MB from ESM bed was performed with distilled water as the desorbing agent, and reuse study was investigated.

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