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This study was undertaken to design a stable easy-recoverable nanoadsorbent (Fe3O4@CM-β-CDP@Tet-Cu(II)) hybrid with rich catalytic sites via wet-chemical method for the catalytic reduction of toxic dyes in wastewater. β-cyclodextrin (β-CD) with a hydrophilic character outside and hydrophobic inside cavity play an important role in catalytic reduction process by interacting with organic molecules and also prepared more sites for further surface modifications. Several characterization techniques including FT-IR, TGA analysis, FE-SEM/EDX, TEM, X-Ray diffraction patterns (XRD) measurements were employed to investigate the structural properties of the synthesized material. The catalytic ability of the obtained material was examined in the presence of different dyes including p-nitrophenol, Eosin Y, Rhodamine B, Congo red, and Methyl orange by UV–Vis spectroscopy as a simple and available method. Moreover, the parameters which effect on reduction process, such as dye and reducing agent (NaBH4) concentrations, mass of adsorbent and time were optimized at room temperature. The obtained data demonstrate the considerable catalytic ability of Fe3O4@CM-β-CDP@Tet-Cu (II) besides a remarkable reduction rate and high yield over a short reaction time, in particular for Methyl orange dye. Recycling experiments revealed that Fe3O4@CM-β-CDP@Tet-Cu (II) has an excellent stability wherein the catalyst was recycled five times with a slight decrease in the reduction ability without any remarkable change in morphological properties which confirm by FE-SEM analysis. The high catalytic activity, the magnetic recoverability, along with the excellent stability of Fe3O4@CM-β-CDP@Tet-Cu (II) make it a potential candidate for the reduction of multiple dyes in real wastewater samples.

The synthesis of new materials of hybrid character (organic-inorganic) doped with dyes results highly attractive like active medium in solid state laser in which the excellent thermal properties of the inorganic glasses with the excellent optic properties of the polymeric materials could be combined. Through a simultaneous synthesis process of sol-gel policondensation of the inorganic TEOS during the free radical polymerization of the organic part (vinylic or acrylic monomers with OH groups), since the presence of this -OH side groups in the organic monomer can participate in the policondensation process of silanols, hybrids monoliths were able to be obtained as solid-state dye laser matrices. The synthesis and characterization of new hybrid matrices were carried out incorporating pirromethene 567 (PM567) into polymers of 2-hydroxyethyl methacrylate (HEMA) and copolymers of HEMA and methyl methacrylate (MMA) with different weight proportions of the inorganic component, tetraethoxysilane (TEOS). The first results obtained with this new materials are indicave that the addition of low proportions of TEOS into the polymer P(HEMA/MMA 1/1) increases its thermal stability reducing the thermal degradation of the dye and, consequently, improving significantly its laser action. In fact, some of the results achieved with these new materials represent the best photostability reached to date for PM567 incorporated into inorganic and hybrid materials and, taking into account the experimental pumping conditions, improve or at least, compare well, with the lasing properties of the dye embedded in other host polymeric matrices.La síntesis de nuevos materiales de carácter híbrido (orgánico-inorgánico) dopados con colorantes resultan altamente atractivos como medio activo en láseres de estado sólido ya que permiten combinar las excelentes propiedades térmicas que presentan los vidrios inorgánicos con las excelentes propiedades ópticas que presentan los materiales polímeros. Mediante un proceso simultaneo de policondensación sol-gel y de polimerización de la parte orgánica (monómero vinílico ó acrílico con grupos OH), de forma que los grupos –OH del monómero orgánico participen también en el proceso de policondensación, hemos conseguido obtener monolitos válidos para su aplicación como láseres de colorante en estado sólido. Se ha llevado a cabo la síntesis y caracterización de nuevas matrices híbridas incorporando pirrometeno 567 como colorante láser (PM567); combinando polímeros de metacrilato de 2-hidroxietilo (HEMA) y copolímeros de HEMA y metacrilato de metilo (MMA) con diferentes proporciones en peso respecto al componente inorgánico (TEOS). Los primeros resultados obtenidos con estos nuevos materiales demuestran que la presencia de pequeñas proporciones de TEOS en copolímeros de p(HEMA/MMA 1/1) aumentan la estabilidad térmica del colorante mejorando significativamente su acción láser. De hecho, algunos de los resultados alcanzados con estos nuevos materiales mejoran, significativamente, las fotoestabilidades alcanzadas para el PM567 incorporado en otras matrices inorgánicas e híbridas, así como en muchas de las matrices orgánicas seleccionadas como hospedadores para este colorante.

The aim of this study was investigate of arsenite adsorption on a hybrid polymer based on a polystyrene/divinylbenzene macroporous anion exchanger containing cupric oxide deposited within its porous structure. The study included batch kinetic and equilibrium experiments, and investigation of influence of the pH, regeneration of spent adsorbent and the column process on arsenic(III) adsorption. The experimental data were evaluated using kinetic, isotherm and fixed-bed column models. The adsorption capacity calculated from the Langmuir model was 6.61 mg As(III) g -1 . The adsorption rate was controlled by both chemisorption of arsenic on the adsorbent surface and external diffusion, and at a higher initial As(III) concentration also by intraparticle diffusion. The spent adsorbent was easily regenerated with 1.0 M NaOH solution. Based on batch adsorption studies and X-ray photoelectron spectroscopic analyses a mechanism of As(III) adsorption was proposed. Arsenite removal proceeded in two stages: oxidation to arsenate on the CuO surface, followed by an ion exchange reaction. The studied hybrid polymer also showed very good adsorption characteristics under the dynamic regime. The S-shape of breakthrough curves and insignificant influence of bed height, initial concentration and flow rate on the adsorption capacity confirmed its applicability in water treatment., (Copyright © 2018 Elsevier B.V. All rights reserved.)