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In dry and hot regions like Morocco, the most expansive soils are clays or marl whose “normal” state is dry and dense.The problems created by these floors in the field of construction are mainly due to the swelling of the floors.We have chosen for this reason to focus our work on the swelling of clay soils which consists in evaluating the influence of the addition of dune sand and exploiting it in geotechnical studies, to stabilize and modify the physical-chemical characteristics and mechanical at different percentages of compressibility, swelling, and consolidation, through oedometric tests.Treated and untreated samples are compacted to the optimum water content (WOpt) and maximum dry density (γDmax). The results of the compressibility tests show that the reconsolidation stress as well as the consolidation of the treated samples is higher than that of the untreated sample, it was also found that the dune sand reduces the compressibility index (Cc), and swelling (Cg),It can be said that stabilization by dune sand significantly improves the mechanical characteristics of the clay studied. The exploitation of the materials studied and to present a clean and profitable alternative in the field of road construction.

Clays considered “problematic” swelling clay soils in the construction of road infrastructures. They generally associated with high compression, high plasticity, and evolutionary behavior. The objective of this article is to study the mechanical behavior of swelling clays and particularly a clay from the Kenitra region. To do this, samples taken from the main clay sites in the region. They then subjected to several series of tests in the laboratory, namely identification tests and mechanical tests (shear test and odometer compressibility test). The results obtained show that the clays studied exhibit very different behaviors. Indeed, the clays of Sidi Slimane, Sidi Kacem and Ouazzane have very interesting mechanical characteristics and can offered in their natural state as road materials, at least for pavements. Ouazzane clay, on the other hand, has very swelling mechanical characteristics (Cg = 0.06), and clay from Sidi Slimane (Cg = 0.04) and Sidi Kacem (Cg = 0.05) and cannot be used in its raw state. Natural without any treatment.

In this study, we applied the modified cationic resin Amberlite®IRC-50 as a biopolymer adsorbent in the technique of adsorption of cationic dyes such as methyl blue (BM) and Safranin (SF) contained in wastewater models. During this technique, we studied the effects of the adsorbent dose and the neutral pH = 6.5 on the adsorption performance, knowing that the mass transfer mechanism was studied using a mass of 0.1 g of the adsorbent Amberlite®IRC50 and a concentration of 20 mg/L for the two colorants MB and SF. The results obtained with regard to the adsorption of these dyes from the present resin have shown that the modification of the surface of the cationic resin Amberlite®IRC-50 has a significant effect on the absorption and its increase has also shown that this process is more compatible with the pseudo-kinetics of the linear second degree model.

In order to optimize and reduce the rate of inorganic micropollutants discharged by various metal facilities, according to wastewater treatment standards and environmental protection, we have proceeded by studying the adsorption of heavy metals such as nickel using sea shells-Mehdia-Morocco as a natural adsorbent. After the preparation of the support, we are interested in the analysis of the physico-chemical parameters influencing the removal of heavy metals such as the kinetics (6.5 to 50 mg.L-1), the initial concentration of the nickel solutions (10 mg.L-1) and the pH of the solution (5.5 to 9.5). All the results obtained show that the adsorption process is favourable to physisorption and monolayer. First, the adsorption amount was found to be 4.05 mg.g−1. Among others, the adsorption process is expressed by the second order kinetic law (R2 = 0.999, 1 / n = 0.37). Moreover, the thermodynamic parameters after using Van't Hoff's equation showed that the studied process has an endothermic, stable and spontaneous effect (ΔG ° = −0.37 Kj.mol−1, ΔH° = 47.31 Kj.mol−1 et ΔS° = 150.56 J.mol−1). Finally, the linear isothermal models of Langmuir (R2 = 0.925), Freundlich (R2 > 0.96) and Temkin (R2 = 0.891), show that the binding and elimination of nickel by this shell is rapid with the increase of the above-mentioned parameters.

The adsorption of methyl orange (MO) dye by artificial zeolites beads, used previously in the removal of heavy metal through the ionic exchange process, has been studied. The effect of several parameters such as temperature, MO concentration, and zeolite mass on MO adsorption was tested in order to determinate optimal conditions. All results have shown that the adsorption process was influenced by the studied parameters. The kinetic data concerning the study of temperature effect was modeled through pseudo-first-order and pseudo-second-order to determinate the adsorption mechanism. Thermodynamic parameters were calculated using the Van’t Hoff equation. Also, they have shown that the studied process has an endothermic, stable and spontaneous nature.

This paper focuses on developing an effective and commercially available adsorbent for cationic dye Safranin (SF). The cationic resin Amberlite ®IRC-50 was chose for this purpose. ®IRC-50 was characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDX) techniques. The adsorption was optimized under various parameters such amount of support, contact time, initial concentration, temperature, pH. Obtained results show the dye adsorption was rapid during the first few minutes and the rate of removal reached over 97% in first 60 min of adsorbent-adsorbate contact time, then leveled off at 120 min. All results have shown clearly, that ®IRC-50 surface is porous and irregular, which is favorable for an efficient adsorption of Safranin dye molecules. The adsorption modeling through kinetic models showed that the adsorption process follows a pseudo-second order model. The retention mechanism has been identified by different adsorption isotherms.

During this present study, we tested the adsorption performance of heavy metal ions; bivalent lead (Pb (II)) and the anionic dye (methyl orange (MO)) from model aqueous solutions with the ion exchange resin of the Amberliteand#174;IRC-50 type. This performance was evaluated using inductively coupled plasma (ICP) and atomic absorption spectroscopy (AAS). The pH of the solution was adjusted to 6.5 for the bath temperature, the initial mass concentration of Pb (II) and MO was adopted at 20 mg/L, the mass of the resin-type adsorbent Amberliteand#174;IRC-50 was taken at 0.1g and the adsorption capacity Qe was studied. The results obtained during this study show that the kinetic study of the adsorption was obtained at the contact time t = 30 min for the metal Pb (II) and at t = 60 min for the dye MO. These results also showed that the equilibrium of adsorption was reached at time t = 60 min with an adsorption performance of around 99% for Pb (II) and around 96% for MO. Note that the parameters of different mathematical models indicate that the adsorption process is spontaneous in the second degree.