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Developing efficient and durable oxygen evolution reaction (OER) catalysts holds great promise for green hydrogen production via seawater electrolysis, but remains a challenge. Herein, we report a Co-doped Ni3S2 nanosheet array on Ni foam (Co-Ni3S2/NF) as a high-efficiency OER electrocatalyst for seawater. In alkaline conditions, Co-Ni3S2/NF requires an overpotential of only 368 mV to drive 100 mA·cm−2, superior to Ni3S2/NF (385 mV). Besides, it exhibits at least 50-h continuous electrolysis. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy of adsorbents from locally sourced olive waste—encompassing olive skins, leaves, and pits, recovered from the initial centrifugation of olives (OWP)—and a composite with sodium alginate (OWPSA) for the removal of Cu2+ ions from synthetic wastewater. Experimental analyses conducted at room temperature, with an initial Cu2+ concentration of 50 mg/L and a solid/liquid ratio of 1 g/L, showed that the removal efficiencies were approximately 79.54% and 94.54% for OWP and OWPSA, respectively, highlighting the positive impact of alginate on adsorption capacity. Utilizing statistical physics isotherm models, particularly the single-layer model coupled to real gas (SLMRG), allowed us to robustly fit the experimental data, providing insights into the adsorption mechanisms. Thermodynamic parameters affirmed the spontaneity and endothermic nature of the processes. Adsorption kinetics were interpreted effectively using the pseudo-second-order (PSO) model. Molecular modeling investigations, including the conductor-like screening model for real solvents (COSMO-RS), density functional theory (DFT), and atom-in-molecule (AIM) analysis, unveiled intricate molecular interactions among the adsorbent components—cellulose, hemicellulose, lignin, and alginate—and the pollutant Cu2+, confirming their physically interactive nature. These findings emphasize the synergistic application of experimental and theoretical approaches, providing a comprehensive understanding of copper adsorption dynamics at the molecular level. This methodology holds promise for unraveling intricate processes across various adsorbent materials in wastewater treatment applications. [ABSTRACT FROM AUTHOR]

In this study, a new eco-friendly kaolinite–cellulose (Kaol/Cel) composite was prepared from waste red bean peels (Phaseolus vulgaris) as a source of cellulose to serve as a promising and effective adsorbent for the removal of crystal violet (CV) dye from aqueous solutions. Its characteristics were investigated through the use of X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and zero-point of charge (pHpzc). The Box–Behnken design was used to improve CV adsorption on the composite by testing its primary affecting factors: loading Cel into the composite matrix of Kaol (A: 0–50%), adsorbent dosage (B: 0.02–0.05 g), pH (C: 4–10), temperature (D: 30–60 °C), and duration (E: 5–60 min). The significant interactions with the greatest CV elimination efficiency (99.86%) are as follows: BC (adsorbent dose vs. pH) and BD (adsorbent dose vs. temperature) at optimum parameters (A: 25%, B: 0.05 g, C: 10, D: 45 °C, and E: 17.5 min) for which the CV's best adsorption capacity (294.12 mg/g) was recorded. The Freundlich and pseudo-second-order kinetic models were the best isotherm and kinetic models fitting our results. Furthermore, the study investigated the mechanisms responsible for eliminating CV by utilizing Kaol/Cel–25. It detected multiple types of associations, including electrostatic, n-π, dipole–dipole, hydrogen bonding interactions, and Yoshida hydrogen bonding. These findings suggest that Kaol/Cel could be a promising starting material for developing a highly efficient adsorbent that can remove cationic dyes from aqueous environments. [ABSTRACT FROM AUTHOR]

In this paper, we investigate a new class of nonlinear fractional integrodifferential systems that includes the Ψ -Riemann–Liouville fractional integral term. Using the technique of upper and lower solutions, the solvability of the system is examined. We add two examples to demonstrate and validate the main result. The main results highlight crucial contributions to the general theory of fractional differential equations. [ABSTRACT FROM AUTHOR]

The significance of using date palm surface fiber as a biosorbent to remove pollutants from wastewater is evaluated. This material, which has advantages over other natural adsorbing materials, for being inexpensive, renewable, eco‐friendly, and available in large scale worldwide, has been widely used for the removal of several types of pollutants such as acid and basic dyes, heavy metals, pesticides, oils, and organic compounds. In addition to its use as an effective biosorbent to remove pollutants from wastewater, date palm surface fiber exhibits wide future perspectives in several other applications. [ABSTRACT FROM AUTHOR]

In this study, 1 wt% platinum (Pt) nanoparticles were incorporated into five types of zeolites (HY, Beta, mordenite, ZSM-5, and ferrierite) with an impregnation technique. The synthesis strategy included the use of water as a solvent for the applied Pt source. Moreover, the incorporation process was performed at ambient conditions followed by calcination at 450 °C. The five prepared materials were characterized by different physical and chemical characterization techniques and the obtained results confirmed the formation of Pt nanoparticles with an average size of 5–10 nm. The catalytic performance of the prepared materials was evaluated in the hydrogenation of cyclohexene under a solvent-free system at room temperature. Pt nanoparticles supported on ZSM-5 zeolite exhibited the best catalytic performance. Moreover, the optimization of operational conditions such as temperature, pressure, and catalyst amount was investigated and the obtained results showed the possibility to convert 100% of cyclohexene within 35 min over Pt-ZSM-5. Finally, the reusability of the Pt-ZSM-5 catalyst was investigated in four consecutive runs without treatment and the obtained results showed a negligible activity loss. [ABSTRACT FROM AUTHOR]

The removal of trivalent chromium [Cr(III)] from tannery wastewater is necessary for health regulation compliance. In this work, two precipitating agents, namely, sodium hydroxide (NaOH) and calcium hydroxide [Ca(OH)2] were used to remove Cr(III) from Amatong Tannery wastewater by chemical precipitation. Wastewater characterization along with the most affecting parameters such as the effect of pH on Cr(III)) removal and sludge volume, average sludge volume and the settling time were investigated. The results show that optimum pH for Cr(III) removal by NaOH and Ca(OH)2 were found as 8.5 and 8.5-9.0, respectively, with supernatant Cr(III) concentration as 1.23 and 4.1 mg/L, respectively; the removal efficiency of NaOH was 99.94% and 99.8% for Ca(OH)2. At optimum pH, NaOH exhibited much sludge volume, whereas Ca(OH)2 displayed higher supernatant volume. NaOH: Ca(OH)2 volume ratio for sludge volume at optimum pH and average sludge volume were 1:1.24 and 1:1.8, respectively. [ABSTRACT FROM AUTHOR]

In this study, a novel and simple synthetic sol-gel procedure was established to directly prepare spherical lead titanate powders without prior synthesis/usage of spherical templates such as TiO2 particles. Isotropic submicron particles with a mean diameter of 1–4 μm were prepared in this way. This synthetic process takes advantage of acetone as a stabilizing ligand and autogenous pressure generated in the autoclave during the reaction. The influence of various experimental factors (nature of the ligand, thermal treatment mode, and post-calcining temperature) as well as the formation mechanism were studied. Scanning electron microscopy and transmission electron microscopy were used to explore the particle morphology. The crystalline phases were explored and identified by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Rhodium (Rh) nanoparticles were embedded in the mesopores of TUD-1 siliceous material and denoted as Rh-TUD-1. Five samples of Rh-TUD-1 were prepared with different loadings of Rh that ranged from 0.1 to 2 wt% using the sol-gel technique. The prepared samples were characterized by means of several chemical and physical techniques. The obtained characterization results show the formation of highly distributed Rh0 nanoparticles with an average size ranging from 3 to 5 nm throughout the three-dimensional silica matrix of TUD-1. The catalytic activity of the prepared catalysts was evaluated in the solvent-free hydrogenation of cyclohexene to cyclohexane at room temperature using 1atm of hydrogen gas. The obtained catalytic results confirm the high activity of Rh-TUD-1, in which a turn over frequency (TOF) ranging from 4.94 to 0.54 s−1 was obtained. Moreover, the change in reaction temperature during the reaction was monitored, and it showed an obvious increase in the reaction temperature as an indication of the spontaneous and exothermic nature of the reactions. Other optimization parameters, such as the substrate/catalyst ratio, and performing the reaction under non-ambient conditions (temperature = 60 °C and hydrogen pressure = 5 atm) were also investigated. Rh-TUD-1 exhibited a high stability in a consecutive reaction of five runs under either ambient or non-ambient conditions. [ABSTRACT FROM AUTHOR]

Four different metal nanoparticles (metal = Ag, Ru, Pt, or Rh) were impregnated on the acidic cesium salt of tungstophosphoric acid Cs2.5H0.5PW12O40 (CsPW) with a loading amount of 2 wt%. The prepared catalysts were characterized by using X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), N2 sorption measurements, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Results confirmed the formation of highly distributed metallic nanoparticle centres over the acidic CsPW. The catalytic activity of the prepared catalysts were evaluated in the liquid phase hydrogenation of methyl isobutyl ketone (MIBK) to 2-methylpentane (2-MP) at 453 K. Pd-CsPW showed the highest activity compared to other catalysts, where 10% conversion was obtained with 91% selectivity after 4 h's reaction time. [ABSTRACT FROM AUTHOR]

[Display omitted] • Well-defined Pt0 nanoparticles were incorporated into TUD-1 by one-step procedure. • The size of Pt0 nanoparticles was in the range of 5–10 nm. • Pt-TUD-1 catalyzed the solvent-free hydrogenation of four different cycloalkenes at room temperature. • Pt-TUD-1 exhibited higher activity than Pt incorporated mordenite, ferrite, or SBA-15. Well-defined Pt nanoparticles were integrated into the mesoporous material TUD-1 by applying one-pot sol–gel methodology and denoted as Pt-TUD-1. The characterization data of Pt-TUD-1 confirmed the presence of highly dispersed nanoparticles of zero-valent platinum (Pt0) of 5–10 nm average size incorporated into the three-dimensional silica framework. Pt-TUD-1 was used to catalyze the liquid-phase hydrogenation of four cycloalkenes; cyclopentene (CPE), cyclohexene (CXE), cyclooctene (COE), and cyclooctadiene (COD) without the use of any solvents in room temperature. The obtained results showed that cyclopentene is the fastest to be hydrogenated where 57.7% was converted within one hour's reaction. The activity of Pt-TUD-1 benchmarked not only the commercial Pt nanopowder but also the Pt supported SiO 2 and SBA-15. Moreover, Pt-TUD-1 showed high stability and it was recycled successfully for four consecutive runs without activity loss. [ABSTRACT FROM AUTHOR]

This research describes the fabrication of the porous trimethylamine (TMA)-grafted anion exchange membrane (AEM) over a phase inversion process. The synthesis of the generated AEM was verified using Fourier transform infrared (FTIR) spectroscopy. The fabricated porous AEM showed 240% water uptake (W R ), 1.45 mg/g ion exchange capacity (IEC), and a 9.0% linear expansion ratio (LER) at 25 °C. It exhibited a porous structure and higher thermal stability. It was utilized to remove eosin B (EB) from wastewater via the process of adsorption. The adsorption capacity of EB increased with time and the starting concentration of EB while decreasing with temperature and the AEM dosage. Adsorption isotherm investigation results showed that EB adsorption onto the porous AEM followed the Langmuir isotherm because the value of correlation coefficient ( R 2 = 0.992) was close to unity. Because the correlation coefficient was close to one, it was determined through adsorption kinetic experiments that the adsorption of EB on the produced porous AEM was suitable for a pseudo-second-order model. Thermodynamic study about process of EB adsorption on the porous AEM revealed that there was an exothermic (Δ H ° = -16.60 kJ/mol) and spontaneous process., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)