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Preparation of Y(PO3)3 polyphosphate was investigated by sol–gel process and solid state synthesis. Crystallization temperature range and purity of samples arising from both synthesis methods were compared. XRD patterns recorded from powders annealed at different temperature evidenced that the stability domain of Y(PO3)3 is much wider for sol–gel derived samples. Furthermore 31P NMR analysis demonstrated the presence of YPO4 impurity along with Y(PO3)3 resulting from solid state route for any sintering temperature. Regarding the sol–gel procedure, effects of the elimination of KCl by-product on the presence of carbon residues in the final materials was studied by IR and Raman spectroscopies as well as EPR measurements. It was shown that when KCl is removed at the end of the synthesis, the crystallization of Y(PO3)3 phase takes place over a very short domain and leads to grey black powder unsuitable for further optical investigations. [ABSTRACT FROM AUTHOR]

Abstract: The yttrium polyphosphate Y(PO3)3 has been synthesized by an all-alkoxide sol–gel route and characterized by X-ray diffraction and IR spectroscopy. The spectroscopic properties of 5% Eu3+ doped samples prepared by the sol–gel process were investigated under site-selective laser excitation in the 5D0 and 5D2 levels of trivalent europium ions, and compared with those of similar compounds synthesized through the conventional solid state reaction. Results showed that one distorted crystallographic site is occupied by Eu3+ ions when spectra are recorded at room temperature. A second site appeared for low temperature measurements in agreement with a phase transition evidenced by a differential scanning calorimetry analysis. These optical results are in disagreement with the already known monoclinic structure of Y(PO3)3 where four sites have been identified at room temperature for lanthanide ions. [Copyright &y& Elsevier]

Abstract: Sol–gel TiO2 thin films have been loaded with platinum nano-particles via their immersion within a Pt4+ precursor liquid solution exposed to UV light. Mechanisms involved in the photo-induced formation of platinum particles have been studied by UV/visible spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray analysis, scanning electron microscopy, and transmission electron microscopy. According to studied mechanisms, it is shown that the amount, size, and structural state of photo-generated platinum particles dispersed at a solid surface can flexibly be monitored. [Copyright &y& Elsevier]

The present study aims to investigate the efficiency of a combined cheese wastewater treatment approach involving coagulation with ferric chloride coupled with a photo-Fenton-like oxidation process for potential reuse in irrigation. Laboratory-scale tests were conducted, examining the effect of various operational parameters on the treatment process. Specifically, the effects of initial wastewater pH, coagulant dosage, decantation time for the coagulation process, and initial pH, chemical oxygen demand (COD) concentration, and Fe 3+ and H 2 O 2 dosages for photo-Fenton-like oxidation were studied. Coagulation was found effective at natural pH of 6 and showed a highest removal efficiency in terms of COD (50.6%), biological oxygen demand BOD 5 (42.1%), turbidity (99.3%), and least sludge volume generation (11.8% v/v) for an optimum coagulant dose of 400 mg Fe 3+ L -1 and 8 h of decantation time. Thereafter, photo-Fenton-like oxidation (Fe 3+ /H 2 O 2 /UVA-300W) of the pretreated cheese effluent enhanced the removal of COD, BOD 5 and TOC to 91.2%, 91.4%, and 97.5%, respectively, using the optimized conditions (pH = 3; [Fe 3+ ] = 5.0 × 10 -4  mol L -1 ; [H 2 O 2 ] = 0.2 mol L -1 and t irr  = 24 h). This study also shows that the proposed combined process allowed a significant phytotoxicity reduction toward lentil seed germination. The obtained outcome was encouraging and supports the possible use of the treated cheese wastewater as an additional water source for agricultural irrigation., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Many approaches have been investigated to eliminate pharmaceuticals in wastewater treatment plants during the last decades. However, a lack of sustainable and efficient solutions exists for the removal of hormones by advanced oxidation processes. The aim of this study was to synthesize and test new photoactive bio composites for the elimination of these molecules in wastewater effluents. The new materials were obtained from the activated carbon (AC) of Arganian spinosa tree nutshells and titanium tetrachloride by the sol gel method. SEM analysis allowed one to confirm the formation of TiO 2 particles homogeneously dispersed at the surface of AC with a controlled titanium dioxide mass ratio, a specific TiO 2 anatase structure, and a highly specific surface area, evidenced by ATG, XRD, and BET analysis, respectively. The obtained composites were revealed to quantitatively absorb carbamazepine (CBZ), which is used as a referred pharmaceutical, and leading to its total elimination after 40 min under irradiation with the most effective material. TiO 2 high content disfavors CBZ adsorption but improves its degradation. In the presence of the composite, three hormones (17α-ethinylestradiol, estrone, and β-estradiol) are partially adsorbed onto the composite and totally degraded after 60 min under UV light exposure. This study constitutes a promising solution for the efficient treatment of wastewater contaminated by hormones.

Nanocomposites based on hydrozincite-TiO 2 and copper-doped HZ-xCu-TiO 2 (x = 0.1; 0.25; 0.35) were synthesized in a single step using the urea method. The samples were characterized by XRD, FTIR, SEM/TEM, and DRS. The study of adsorption capacity and photocatalytic efficiency of these nanocomposites have been tested on a pharmaceutical pollutant, mefenamic acid (MFA). Kinetic study of removal of MFA indicates that this pollutant was adsorbed on the surface of the synthesized phases, according to Langmuir's model. Such adsorption proved to be well adapted in a kinetic pseudo-second-order model with capacity of 13.08 mg/g for HZ-0.25Cu-TiO 2 . Subsequently, the kinetics of photocatalytic degradation under UV-visible irradiation was studied according to several parameters, which allowed us to optimize our experimental conditions. The nanocomposite HZ-0.25Cu-TiO 2 showed significant removal efficiency of MFA. Elimination rate reached 100% after 20 min under UV-vis irradiation, and 77% after 7 h under visible light irradiation. Repeatability tests have shown that this nanocomposite is extremely stable after six photocatalytic cycles. By-products of MFA were detected by LC/MS. These photoproducts was produced by three types of reactions of hydroxylation: cyclization and cleavage of the aromatic ring. MFA underwent complete mineralization after 22 h of irradiation in the presence of the HZ-0.25Cu-TiO 2 ., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Diglycidyl amino benzene (DGAB) epoxy prepolymer was investigated using Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Then, we highlighted the usefulness of DGAB epoxy prepolymer to improve the resistance of carbon steel (CS) in hydrochloric acid (1.0 M HCl) using weight loss (WL), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), scanning electron microscope (SEM), atomic force microscopy (AFM), density functional theory (DFT) and complexation calculations, molecular dynamics (MD) and meansquaredisplacement (MSD) simulations. Highest inhibitory efficiencies for the WL, EIS and PDP methods at 10 -3 M of DGAB are 90.8, 96.3 and 95.9%, respectively. SEM and AFM micrographs demonstrated that the epoxy prepolymer could effectively block the acid attack by chemisorption on the surface of the carbon steel, the high correlation coefficient and low Standard Deviation (SD) and low Sum of Squares (SS) value gave the best fit for Langmuir isotherm. PDP data suggested that the epoxy prepolymer could provide excellent corrosion performance and showed a mixed-type inhibitor with predominant cathodic effectiveness. Investigate of the inhibitory layer and the potential mechanism was conceptually evaluated using DFT, MD simulations, radial distribution function (RDF) and mean square displacement (MSD)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

This work was dedicated to the elaboration of new composite materials based on activated carbon and titanium oxide as an ecological solution for the cleaning of water contaminated with pharmaceutical pollutants. Such new composite materials allowed the combining of adsorption and photocatalytic process, which allows a cleaning process that is low cost making them promising materials. The functionalization of the surface of activated carbon (AC) by TiO 2 nanoparticles forms the core of the nanocomposite material. This was accomplished using sol-gel process with molar ratios R n (n Ti /n AC ) in the range of 1/10 to 7/10 followed by a calcination step (400 °C, N 2 , 2 h). Using various characterization techniques, AC surface functionalization was confirmed and the formation of a TiO 2 coating on the AC was noticed with TiO 2 under its unique anatase crystallographic form. The study of adsorption and photocatalytic degradation of the sulfamethazine antibiotic demonstrated that the most photoactive nanocomposite corresponds to the one with R n  = 0.5. Freundlich model was proved to be a perfect fit with the experimental results stating that the adsorption is of multilayer nature on the surface of the adsorbent and with interactions between the pollutants adsorbed on its surface. The photocatalytic degradation of the remaining pharmaceutical pollutant in the solution was evidenced and essentially occurred through the involvement of hydroxyl radicals formed by the excitation of the photocatalyst. The formation of the photoproducts analyzed by the LC/MS technique implies the splitting of the sulfonamide bridge, and by the hydroxylation of the aromatic ring and the pyrimidine group.