Micro-structure and gel performance of octadecyl trimethyl ammonium chloride intercalated montmorillonite

Sulfadiazine removal with low-cost structured nano and micro-composite hydrogel beads on moroccan clays with alginate-CMC-biochar

The primary goal of the current work was to construct pH-sensitive nano and microcomposite hydrogel beads based on alginate (AL), carboxymethyl cellulose (CMC), biochar (BC), and two Moroccan clays: Ghassoul (swelling SW) and red (not swelling NSW) nano and microhybrid. The adsorbents, SW + AL, SW + AL + BC, SW + AL + CMC, NSW + AL, NSW + AL + BC, NSW + AL + CMC, AL, and AL + CMC were prepared for the adsorption of the antibiotic sulfadiazine (SDZ). The test samples were characterized using a variety of techniques, including X-Ray Diffraction (XRD), IR spectroscopy (FT-IR), and scanning electron microscopy (SEM), with the molecular structures of the studied additives geometrically optimized using the DFT/B3LYP method and the function 6-311G(d). Molecular electrostatic potential (MEP) and Mulliken charge analysis were utilized to estimate the adsorption sites of the additives under study, with conformational analysis using Monte Carlo (MC) simulations and Hirshfeld surface (HS) analysis to gain a better understanding of the SDZ's adsorption process on the clay and polymer surfaces through its sulfonyl, amino, and carboxylate groups. The study found that SW + AL + CMC beads had a maximum adsorption capability of 800 μmol/kg for SDZ. Furthermore, this composite demonstrated more than 100% adsorption and 0% subsequent desorption. The findings of this study point to the possibility of using SW + AL + CMC nanocomposite for SDZ removal, which would be useful for the environment and public health.

New Organophilic Montmorillonites with Lactic Acid Oligomers and Other Environmentally Friendly Compounds and Their Effect on Mechanical Properties of Polylactide (PLA)

New organophilic montmorillonites with oligomers of lactic acid and other compounds such as citric acid, stearic acid, maleic anhydride, pentaerythritol and ε-caprolactone were synthesized. They were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), elemental analysis and swelling capacity in water. In all tested composites, an increase in the montmorillonite interlayer distance resulting from intercalation of the modifying substance in the montmorillonite was found by means of XRD. Elemental analysis and FTIR showed that all of the tested samples contained an organic segment in the montmorillonite structure. TGA studies revealed that composites modified with lactic acid oligomers, stearic acid or ε-caprolactone had the highest thermal stability. They also exhibited the lowest swelling capacity which was 2-3 times lower than that for unmodified sodium montmorillonite. Some preliminary studies on the mechanical properties of PLA/modified montmorillonite are also presented and discussed.

The adsorption characteristics and mechanism of montmorillonite with different layer charge density for alkyl ammonium with different carbon chain length

The crystal chemical properties of montmorillonite and the length and amount of straight alkyl ammonium chain affect the adsorption characteristics of alkyl ammonium on montmorillonite.