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Polypropylene nonwoven supports carrying ␣-, ␤-, and ␥-cyclodextrins (CDs) were synthezised. The synthesis consisted of grafting glycidyl methacrylate (GMA) onto the fibers and reacting CDs with epoxide groups in the second step. This article concerns the sorption capacity of these supports toward organic pollutant models of 2-naphtol, 4-nitrophenol, pentachlorophenol, and (2,4-dichlorophenoxy) acetic acid in static (batch) or dynamic (filtration) conditions. The results confirmed that the grafting of CDs onto the supports gave them their specific sorption properties. Besides, it was observed that the best performances were attained when the GMA add-on was in the range of 76 -113 % wt and the CD content was 87-118 mol/g. We also evidenced that the interactions between the organic substrates and the filter occurred through specific interactions with CDs (host-guest inclusion compounds) and that to a lesser extent, nonspecific sorption phenomena also occurred. The data showed that the affinity between the pollutants with three different grafted CDs was not in agreement with the complex formation constants measured in homogeneous systems. Furthermore, the slow kinetics of exchange between the liquid and solid phases was a limiting factor that should prevent the use of the filters at elevated flow rates. At last, the great advantage of these filters is that they could undergo several cycles of use, thanks to intermediate regeneration steps with water-organic solvent mixtures.

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A series of poly(ethylenimines) (PEI) coated onto silica gels has been tested for the ability to complex lead and mercury in aqueous solutions. The study of the kinetics of metal uptake revealed that all sorbents exhibit a fast rate of sorption. The saturation capacities of the different systems were evaluated according to the Langmuir equation. The influence of different parameters like pH, textural characteristics of silica, and amount of coated polymer were discussed. Finally, cycles of stripping and sorption for lead metal were investigated in column system to evaluate the long-term stability of the sorption properties. One striking result was that crosslinking PEI onto silica prevents the desorption of PEI and greatly improves the sorption capacity.

A novel adsorbent for heavy metals, functionalized with conjugated β-ketoenol Furan, was fabricated using a simple heterogeneous method. The adsorbent design (SiNFn) was well analyzed and characterized by the techniques of solid state 13 C NMR, Fourier transform-infrared spectroscopy (FT-IR), elementary analysis, nitrogen adsorption−desorption isotherm, BET surface area, BJH pore sizes, and scanning electron microscopy (SEM). The new surface has good thermal stability determined by thermogravimetry curves analysis (TGA), and a good chemical stability investigated in various acidic and buffer solutions. The effect of various parameters on Cd(II), Cu(II), Zn(II), and Pb(II) adsorption, such as pH, concentration, temperature, competitive extraction, thermodynamics and kinetics studies, and extraction of metals from real water samples were investigated. The results indicated that the adsorption efficiency increases with increasing pH and follows pseudo-second-order kinetics. Adsorption was rapid as evidenced by equilibrium achieved within 25 min. The adsorption isotherm was better described by a Langmuir compared to a Freundlich isotherm equation. The thermodynamic parameters (ΔH°, ΔS°, and ΔG°) revealed that the adsorption was spontaneous and endothermic. The competitive adsorption exhibited high selectivity toward Cd(II). The new material was applied to the extraction of metals from two real waters: Touissit-Boubeker River and Giss River (Morocco) and shows efficiency and selectivity results especially for Cd(II).