Selective chemical adsorption of Cd(ii) on silica covalently decorated with a β-ketoenol-thiophene-furan receptor

Nowadays, porous hybrid materials are considered as potential reservoirs of metallic species in environmental clean-up technologies. Herein, a new environment-friendly surface with thiophene-furan-β-ketoenol grafted on a colloidal silica surface has been synthesized with the purpose of using it as an effective and selective adsorbent for Cd(II) from aquatic environments. Elemental analysis, Fourier-transform infrared spectroscopy, scanning electronic microscopy, thermogravimetric analysis and Brunauer–Emmett–Teller analysis confirm the successful surface incorporation of the β-ketoenol bis-heterocycle receptor. The novel inorganic–organic hybrid material was applied for Cd(II), Cu(II), Zn(II) and Pb(II) adsorption. Cd(II) adsorption reaches 84.45 mg g−1 within only 30 min at pH 6, and the adsorption was more appropriate with the 2nd order kinetic model (R2 ≥ 0.997) and Langmuir model isotherm where the adsorption process is coherent with a monolayer adsorption reaction. The ΔH°, ΔS° and ΔG° parameters reflect spontaneous, and endothermic adsorption and that the process increases the randomness. The new material demonstrates its efficiency and selectivity towards Cd(II) and promises good reusability for at least five elimination cycles. The new material can be considered as a reliable cleaner of Cd(II) from aquatic environments

New Adsorbent Material Based on Nitrothiophene-Functionalized Silica Particles for Aqueous Heavy Metals Removal

International audience[No abstract

Crystal structure of (Z)-1-(1,5-dimethyl-1H-pyrazol-3-yl)-3-(4-ethoxyphenyl)-3-hydroxyprop-2-en-1-one, C16H18N2O3

International audienc

Crystal structure of (Z)-3-hydroxy-3-(4-methoxyphenyl)-1-(pyridin-2-yl)prop-2-en-1-one, C15H13NO3

International audienc

Crystal structure of (Z)-1-(1,5-dimethyl-1H-pyrazol-3-yl)-3-hydroxy-3-phenylprop-2-en-1-one, C14H14N2O2

International audienc

Crystal structure of (Z)-1-(1,5-dimethyl-1H-pyrazol-3-yl)-3-hydroxy-3-(4-methoxyphenyl)prop-2-en-1-one, C15H16N2O3

International audienc

Quantitative Removal of Zn(II) from Aqueous Solution and Natural Water Using New Silica-Immobilized ketoenol–pyridine Receptor

International audience[No abstract

Efficient and Environment-Friendly Adsorbent Based on β-Ketoenol-Pyrazole-Thiophene for Heavy Metal Ion Removal from Aquatic Medium: A Combined Experimental and Theoretical Study

A new sustainable and environmentally friendly adsorbent based on a β-ketoenol-pyrazole-thiophene receptor grafted onto a silica surface was developed and applied to the removal of heavy metal ions (Pb(II), Cu(II), Zn(II) and Cd(II)) from aquatic medium. The new material SiNPz-Th was well characterized and confirms the success of the covalent binding of the receptor on the silica surface. The effect of environmental parameters on adsorption including pH, contact time, temperature and the initial concentration were investigated. The maximum adsorption capacities of SiNPz-Th for Pb(II), Cu(II), Zn(II) and Cd(II) ions were 102.20, 76.42, 68.95 and 32.68 mg/g, respectively, at 30 min and pH = 6. The adsorption isotherms, kinetics and thermodynamic process were investigated and showed efficiency and selectivity towards Pb(II) and good regeneration performance. Density functional theory (DFT), non-covalent-interaction (NCI) and quantum theory of atoms in molecules (QTAIM) calculations were used to study and to gain a deeper understanding of both adsorption mechanism and selectivity of metal ions onto adsorbent. Accordingly, the metal ions such as Pb(II), Cu(II) and Zn(II) are bidentate coordinated with the adsorbent by nitrogen and oxygen atoms of Schiff base C=N and hydroxyl group –OH, respectively, to form stable complexes. While the Cd(II) is coordinated in a monodentate fashion with oxygen atom of hydroxyl group. Furthermore, the affinity of SiNPz-Th towards the metal ions was decreased in the order of Pb(II) ˃ Cu(II) ˃ Zn(II) ˃ Cd(II), in good agreement with experimental results. All these results highlight that the SiNPz-Th has a good potential to be an advanced adsorbent for the removal of lead ions from real water

Organically Modified Silica with Pyrazole-3-Carbaldehyde as a New Sorbent for Solid-Liquid Extraction of Heavy Metals

International audienceA new chelating matrix, SiNP, has been prepared by immobilizing 1.5-dimethyl-1H-pyrazole-3-carbaldehyde on silica gel modified with 3-aminopropyl-trimethoxysilane. This new chelating material was well characterized by elemental analysis, FT-IR spectroscopy, cross polarization magic angle spinning solid state 13C-NMR, nitrogen adsorption-desorption isotherm, BET surface area, BJH pore size, and scanning electron microscopy (SEM). The new product exhibits good chemical and thermal stability as determined by thermogravimetry curves (TGA). The new prepared material was used as an adsorbent for the solid-phase extraction (SPE) of Pb(II), Cd(II), Cu(II) and Zn(II) from aqueous solutions using a batch method, prior to their determination by flame atomic adsorption spectrometry. The adsorption capacity was investigated using kinetics and pH effects. Common coexisting ions did not interfere with separation and determination