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Sorption study of alkylimidazolium salts on a bentonite aims at elaborating organophilic organoclay materials likely to be used in the separation of organic compounds of diverse polluted effluents. Therefore, the action of bromide and hexafluorophosphate salts of several alkyl-3-methylimidazolium, with long hydrocarbon chains (C10–C18), on a calcic bentonite was followed by several analysis methods. The analysis results reveal the insertion of alkylimidazolium cations between layers of clay, the adsorption extent of alkylimidazolium salts on surfaces of treated clays and presence of bonds relative to fixed organic salts. The contribution of activation by microwave irradiations on adsorption and insertion of bentonite was also studied (90 W for 5–30 min) and the obtained results were compared with those obtained under classical conditions (room temperature for 24 h). It was found that adsorption and intercalation capacities become quicker and more important under microwave activation. This insertion phenomenon becomes more and more significant with the irradiation time and the excess of imidazolium salts. The original point of the paper carries on the activation by microwave irradiations on bentonite insertion.

International audience; The present work addresses the students in chemistry, chemical engineering of the environment, as well as the specialists in chemistry of the phosphorus and the organophosphate compounds, in Hydrometallurgy both at the industrial level and at the level of the scientific research. This work aims to be a guide for the chemistry of the agent's complexants of types phosphonic & aminophosphonic acids, consisted widely used in the liquid-liquid extraction for the extraction of metals and rare earths, in the proceeding of ores and in the aqueous effluent treatments for the recovery and the valuation of rare earths, N-C-P in medicinal chemistry, pesticides/herbicides and water-decontamination systems, organometallic complexes: MOF, gas absorption, proton conductivity and Magnetic shielding tensors.  Broché : 108 pages  Editeur : Éditions universitaires européennes (15 janvier 2018)  Langue : Anglais 

After the synthesis of polyethylenimine supported on silica, it has been used as a new and efficient catalyst in Knoevenagel and Michael condensations. The presence of the polyethylenimine in the catalytic system together with silica displays an acido-basic character allows a better catalytic activity in the condensations. Carried out under microwave irradiation, without organic solvent and during short time, the syntheses are respectful towards green chemistry. The solid catalyst can be easily reused. This catalyst has the acido-basic character at the same time.

Batch experiments are carried out for the sorption of La(III) onto commercial macroporous resins containing iminodiacetic (Lewatit TP 207) and aminomethylphosphonic acid groups (Lewatit TP 260). The operating variables studied are initial La(III) concentration, pH, temperature and contact time. Since the extraction kinetics were fast, with a mixture of 0.1 g of resin and 5 mL of lanthanum ions 0.5 × 10−3 mol L−1 solution, extraction equilibrium was reached within 30 min of mixing. The optimum pH values level for quantitative sorption were between 1.5 and 4.6 with Lewatit 207 and about 5.2 with Lewatit TP 260. The sorption capacities of Lewatit TP 207 and Lewatit TP 260 resins are 114.7 and 106.7 mg g−1, respectively. Adsorption equilibrium data were calculated for Langmuir and Freundlich isotherms. It was found that the sorption of La(III) on Lewatit TP 207 was better suited to the Langmuir adsorption model while Freundlich adsorption model fitted better sorption on Lewatit TP 260. Thermodynamics data leads to endothermic and spontaneous process. ΔG° decreases with increasing temperature indicating that sorption process of La(III) on both Lewatit TP 207 and Lewatit TP 260 was more favored at high temperature.

Liquid-solid extraction of Thorium (IV) is made by sodium bentonite and Magnetic bentonite. Magnetic adsorbent can be quickly separated from a medium by a simple magnetic process, in view of these properties, some parameters were studied to assess the performance of maghemite nanocomposite clay for the removal of Thorium ions. The operating variables studied are initial Th (IV) concentration, pH, ionic strength, temperature and contact time. The time needed for magnetic bentonite to adsorb the maximum of Th (IV) is 45 minutes and 60 minutes for sodium bentonite. For magnetic bentonite, optimal extraction yield was achieved in a initial pH equal at 6.2 and for sodium bentonite, the variation of initial pH has no influence on the extraction yield. The sorption capacities of sodium bentonite and magnetic bentonite are 41.24 and 31.34 mg.g-1 respectively. Adsorption equilibrium data were calculated for Langmuir and Freundlich isotherms. It was found that the sorption of Th (IV) on sodium and magnetic bentonite was better suited to the Langmuir adsorption model. Thermodynamics data leads to endothermic and spontaneous process for magnetic bentonite and exothermal for sodium bentonite. The quantitative elution study of Thorium can be realized with acetic acid for sodium bentonite and sulfuric acid for magnetic bentonite., European Chemical Bulletin, Vol 4, No 10-12 (2015): European Chemical Bulletin

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This study aims to investigate the Lewatit TP 214, which is a chelating ion-exchange polymer containing the thiourea group, for the sorption of Pb(II) and Cd(II) ions from aqueous solutions. The thiourea function is chemically bonded to the matrix of the styrene-divinylbenzene polymer. The effects of parameters such as the concentration, pH level, contact time, ionic strength and temperature were investigated. The results showed more affinity of resin towards cadmium than lead cations. The maximum uptake values of Pb(II) and Cd(II) were 55.59 mg.g-1 and 81.75 mg.g-1, respectively. The resin used in this study exhibited a good sorption potential at initial pH values, i.e. pH = 4.1 and pH = 6.1, for Pb(II) and Cd(II), respectively, at room temperature. The extraction kinetics, for both cations Pb(II) and Cd(II), was best described by the pseudo second order model. This study showed that the diffusion of moving boundary particles fits well the experimental data (r > 0.99) for the sorption of both Pb(II) and Cd(II) ions. The Langmuir isotherm fits better the obtained equilibrium data compared to the Freundlich isotherm. The thermodynamic data for the sorption of Pb(II) and Cd(II), on the Lewatit 214 resin, indicate that the process is endothermic for Pb(II) (∆H = + 8.94 kj.mol-1), while it is exothermic for Cd(II) (∆H = - 51.65 kj.mol-1). In addition, the thermodynamic study showed also negative ∆G values, indicating that the sorption process of both Pb(II) and Cd(II) ions is spontaneous., European Chemical Bulletin, Vol 4, No 7-9 (2015): European Chemical Bulletin

The sorption of mercury (II) from aqueous medium on a chelating resin Chelex 100 has been studied in batch mode. Since the extraction kinetic was obtained, with a mixture of 0.1 g of resin and 5 mL of mercury (II) at 200. 59 mg/L of initial concentration, extraction equilibrium was reached within 180 min of mixing. The influence of some parameters such as initial mercury (II) ion concentration, initial pH of aqueous solution, ion strength and the amounts of resin have been studied at fixed temperature (20±1 °C). The optimum pH value level for quantitative sorption was 5.7. The best performance obtained was 98.0% of extraction yield equivalent to 14.19 mg /g of resin. The pseudo-first- order equation, pseudo-second-order equation, the intra-particle diffusion model and Boyd’s diffusivity model were used to describe the kinetics data and rate constants were evaluated. The Freundlich and Langmuir adsorption models were applied to describe the equilibrium isotherms., European Chemical Bulletin, Vol 3, No 9 (2014): European Chemical Bulletin

New complexone derivatives of 8-hydroxyquinoline (quinolinol) were synthesized by the Mannich reaction from secondary and primary amines. Our syntheses were carried out either at room temperature, at reflux or under microwave irradiation, in good yields. The use of the 7-(dioctylamino)methyl)quinolin-8-ol (3f) as new extractant for the uptake and removal of UO22+ was investigated. Conditions for an effective sorption were optimized. The total sorption capacity was 102 (mg.g-1) under optimum experimental conditions., European Chemical Bulletin, Vol 3, No 8 (2014): European Chemical Bulletin

New complexone derivative of 8-hydroxyquinoline (quinolinol) was synthesized by the Mannich reaction from secondary and primary amines. Our synthesis was carried out either at room temperature or at reflux in good yields. Various analytical techniques (1H & 13C NMR, FTIR, Mass spectroscopy) were used to characterize our product. The use of this new extractant for the uptake and removal of UO22+ in aqueous solution was investigated. Conditions for an effective sorption were optimized with respect to different experimental parameters in batch process. The total sorption capacity was 102 (mg.g-1) under optimum experimental conditions. Thermodynamic parameters showed the adsorption of an endothermic process and a spontaneous nature, respectively., Moroccan Journal of Chemistry, Vol 2, No 5 (2014): Proceedings of the fourth edition of the International Congress Water, Waste & Environment