Synthesis of Polytetrahydrofuran Using Protonated Kaolin as A Solid Acid Catalyst

In this work, a non-toxic protonated kaolin clay exchanged with protons, was successfully applied as a solid acid catalyst for the polymerization of tetrahydrofuran (poly(THF)) at room temperature in the presence of acetic anhydride. Prior to using the kaolin as a catalyst, it was treated with HCl (0.1 M) and characterized using various analytical techniques. The amounts of catalyst and reaction time on the conversion of THF were investigated. Characterizations of nuclear magnetic Resonance of proton (1H-NMR), Fourier Transform Infrared spectroscopy (FT-IR), X-ray Diffraction (XRD), Optical Microscopy (OM), and Differential Scanning Calorimetry (DSC) techniques were used to examine the resulting polymer. X-ray characterization and DSC data indicated that the obtained poly(THF) is a highly crystalline substance. The results showed that protonated kaolin (kaolin–H+) has a high catalytic activity for the polymerization of THF with a conversion rate of 50.02% after 20 hours. Copyright © 2019 BCREC Group. All rights reserved

Removal of 4-(2-pyridylazo)-Resorcinol from Aqueous Solution Using Natural and Activated Algerian Kaolin

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Structural and optical proprieties of [M(8-HQ)2(H2O)2] {M = Ni(II), Co(II)} thin films deposed by chemical bath deposition method

The objective of this study was the deposition of thin films of 8-hydroxyquinolin (8-HQ) Cobalt(II) and Nickel(II) complexes onto glass substrates using the chemical bath deposition (CBD) method. The deposition experiments were carried out under the effect of some physicochemical factors such as solution temperature (25 °C–55 °C), medium pH (1–6), metal: ligand molar stoichiometric ratio (1:1–1:3), and immersion time (in the range 10–60 min). The obtained thin films were characterized using many analytical methods (UV-Vis spectrophotometry, infrared spectrophotometry, optical microscopy, scanning electron microscopy, and X-ray diffraction). The study of the optical properties of the obtained thin films showed that the complexes [Ni(8-HQ)2(H2O)2] and [Co(8-HQ)2(H2O)2] have strong absorbance in UV area corresponding to a π-π* or n-π* electronic transition between the HOMO and the LUMO with a gap’s energy in the range 4.1 and 4.4 eV. In the light of the optical measurements, [Ni(8-HQ)2(H2O)2] and [Co(8-HQ)2(H2O)2] complexes can be considered as semiconductors