Effective phosphorus removal using transformed water hyacinth: Performance evaluation in fixed-bed columns and practical applications.

This study introduces calcined water hyacinth (CWH), processed at 650°C, as a novel and environmentally friendly adsorbent for phosphorus (P) removal from wastewater. Building on previous findings that identified CWH as a rich source of metal oxides and hydroxides (e.g.

Molecular insights and thermodynamic feasibility of phosphate adsorption on Ca-biocomposites using a simplified carbon structure.

The removal of phosphorous from water sources is a critical challenge in mitigating water eutrophication. Adsorption using Ca-biocomposite-derived materials has proven to be highly effective for phosphorus removal. These biocomposites contain Ca, CaO, and Ca-(hydr)oxide species, which form Ca-P apatite phases, a potential fertilizer, holding promise for phosphorus recycling and promoting a circular economy.

Encapsulation of charged halogens by the 5 water cage.

This study focuses on the encapsulation of the entire series of halides by the 5 cage of twenty water molecules and on the characterization of water to water and water to anion interactions. State-of-the-art computations are used to determine equilibrium geometries, energy related quantities, and thermal stability towards dissociation and to dissect the nature and strength of intermolecular interactions holding the clusters as stable units. Two types of structures are revealed: heavily deformed cages for F indicating a preference for microsolvation, and slightly deformed cages for the remaining anions indicating a preference for encapsulation.

Performance of novel Ca-biocomposites produced from banana peel and eggshell for highly efficient removal and recovery of phosphate from domestic wastewater.

Using biowaste-based adsorbents to remove phosphorus (P) from wastewater offers significant benefits concerning eutrophication mitigation and addressing waste management challenges. In this work, Ca-biocomposites were prepared by pyrolysis (700 °C) of a mixture of banana peel (BP) and eggshell (ES). The mass ratio of BP to ES was varied in 2:1, 1:1, and 1:2 ratios.

Sargassum macroalgae from Quintana Roo as raw material for the preparation of high-performance phosphate adsorbent from aqueous solutions.

Currently, the large volumes of Sargassum biomass (Sgs) arriving on Caribbean coasts are a problem that must be solved quickly. One alternative is to obtain value-added products from Sgs. In this work, Sgs is demonstrated to be a high-performance Ca - bioadsorbent for phosphate removal by a heat pretreatment at 800 °C that produces biochar.

Encapsulation of Astatide by a water cage.

A 5 cage of (HO) consisting of 30 hydrogen bonds encapsulates Astatide with little geometrical distortion. The cage is marginally destabilized but the non-covalent interactions are actually strengthened. Host⋯cage interactions in the [At@(HO)] cluster are anti-electrostatic, placing both negatively charged atoms in direct contact as in At⋯O-H.

Biochar from palm fiber wastes as an activator of different oxidants for the elimination of pharmaceuticals from diverse classes in aqueous samples.

Biochar (BP) obtained from palm fiber wastes was combined with HO, peroxymonosulfate (PMS), or persulfate (PDS) to treat valsartan, acetaminophen, and cephalexin in water. BP activated PMS and PDS but no HO. Computational calculations indicated that interactions of PMS and PDS with BP are more favored than those with HP.

Application of Orange Peel Waste as Adsorbent for Methylene Blue and Cd Simultaneous Remediation.

Pollution by dyes and heavy metals is one of the main concerns at the environmental level due to their toxicity and inefficient elimination by traditional water treatment. Orange peel (OP) without any treatment was applied to effectively eliminate methylene blue (MB) and cadmium ions (Cd) in mono- and multicomponent systems. Although the single adsorption processes for MB and Cd have been investigated, the effects and mechanisms of interactions among multicomponent systems are still unclear.

Microsolvation versus Encapsulation in Mono, Di, and Trivalent Cations.

The effects of the formal charge in the stability and bonding of water cavities when solvating a cation are studied here using [X(H O) ] clusters starting with the well known 5 isomer of (water) , placing a single mono, di, or trivalent X cation at the interior, and then optimizing and characterizing the resulting clusters. Highly correlated interaction and deformation energies are calculated using the CCSD(T)-DLPNO formalism. Bonding interactions are characterized using the tools provided by the quantum theory of atoms in molecules, natural bond orbitals, and non-covalent surfaces.

Effect of nanostructuring on the interaction of CO with molybdenum carbide nanoparticles.

Transition metal carbides are increasingly used as catalysts for the transformation of CO into useful chemicals. Recently, the effect of nanostructuring of such carbides has started to gain relevance in tailoring their catalytic capabilities. Catalytic materials based on molybdenum carbide nanoparticles (MoC) have shown a remarkable ability to bind CO at room temperature and to hydrogenate it into oxygenates or light alkanes.

To Be or Not To Be? that is the Entropic, Enthalpic, and Molecular Interaction Dilemma in the Formation of (Water) Clusters and Methane Clathrate.

A detailed analysis under a comprehensive set of theoretical and computational tools of the thermodynamical factors and of the intermolecular interactions behind the stabilization of a well known set of (water) cavities and of the methane clathrate is offered in this work. Beyond the available reports of experimental characterization at extreme conditions of most of the systems studied here, all clusters should be amenable to experimental detection at 1 atm and moderate temperatures since 280 K marks the boundary at which, ignoring reaction paths, formation of all clusters is no longer spontaneous from the 20H O→(H O) and CH +20H O→CH @5 processes. As a function of temperature, a complex interplay leading to the free energy of formation occurs between the destabilizing entropic contributions, mostly due to cluster vibrations, and the stabilizing enthalpic contributions, due to intermolecular interactions and the PV term, is best illustrated by the highly symmetric 5 cage consistently showing signs of stronger intermolecular bonding despite having smaller binding energy than the other clusters.

Valorization of potato peels and eggshells wastes: Ca-biocomposite to remove and recover phosphorus from domestic wastewater.

Potato peel (PP) waste are generated in huge quantities, causing environmental pollution and health problems. Therefore, obtaining value-added products from PP is a current research challenge. In this work, novel Ca-biocomposites for phosphorus (P) removal were prepared by pyrolysis (500-800 °C) using eggshell (ES) and PP (ES/PP = 1:2 ratio by weight).

Unraveling the Ca-P species produced over the time during phosphorus removal from aqueous solution using biocomposite of eggshell-palm mesocarp fiber.

Phosphorus (P) adsorption from aqueous solutions is usually evaluated by monitoring the P concentration and employed kinetic models. In this work, three adsorbents obtained from eggshell (ES) and eggshell mixed with palm mesocarp fiber (ESF-1:1 and ESF-1:10) at different Ca(OH)/CaCO compositions were evaluated, and the Ca-P species formed monitored as a function of time deconvoluting Fourier Transform Infrared (FTIR) spectra. At 0.

Spot the difference: hydrogen adsorption and dissociation on unsupported platinum and platinum-coated transition metal carbides.

Hydrogenation reactions are involved in several processes in heterogeneous catalysis. Platinum is the best-known catalyst; however, there are limitations to its practical use. Therefore, it is necessary to explore alternative materials and transition metal carbides (TMCs) have emerged as potential candidates.

Experimental and Theoretical Insights on Methylene Blue Removal from Wastewater Using an Adsorbent Obtained from the Residues of the Orange Industry.

Chemical and thermochemical transformations were performed on orange peel to obtain materials that were characterized and further tested to explore their potential as adsorbents for the removal of methylene blue (MB) from aqueous solutions. The results show the high potential of some of these materials for MB adsorption not only due to the surface area of the resulting substrate but also to the chemistry of the corresponding surface functional groups. Fitting of the kinetic as well as the equilibrium experimental data to different models suggests that a variety of interactions are involved in MB adsorption.

Kinetics, isotherms, effect of structure, and computational analysis during the removal of three representative pharmaceuticals from water by adsorption using a biochar obtained from oil palm fiber.

Acetaminophen (ACE), cephalexin (CPX), and valsartan (VAL) are recognized water pollutants, which can be removed by adsorption. Herein, the removal of these pharmaceuticals using a biochar (BP), prepared from oil palm fiber, was tested. It was studied the structural effects of the pharmaceuticals and biochar on the adsorption process supported by experimental and computational results, plus characterizations of the material.

Understanding mechanisms in the adsorption of lead and copper ions on chili seed waste in single and multicomponent systems: a combined experimental and computational study.

In the current work, a deep study to understand the adsorption phenomena occurring in single and multicomponent systems was conducted by using spectroscopic characterization, and computational tools. The experimental results showed that the adsorption capacity of chili seed is higher for Pb (48 mg/g) than Cu (4.1 mg/g) ions in single systems.

Promoting effect of tungsten carbide on the catalytic activity of Cu for CO reduction.

The adsorption of H, CO2, HCOO, O and CO on copper monolayers and submonolayers supported on hexagonal WC(0001) surfaces has been investigated. Calculations have been performed using density functional theory with the Perdew-Burke-Ernzerhof exchange correlation functional and D2 van der Waals corrections. In addition, dipole corrections were also included.

Role of Transition Metals on TM/MoC Composites: Hydrogen Evolution Activity in Mildly Acidic and Alkaline Media.

Modification of electronic and chemical properties of a material by the introduction of another element into its lattice is one of the most common methods for designing new catalysts for different applications. In this work the effect of modifying molybdenum carbide with transition metals (Fe, Co, Ni, Cu), TM-MoC composites, upon the catalytic activity toward hydrogen evolution reaction (HER) in mild acidic and alkaline media has been studied. Catalysts were prepared by carbothermal reduction of molybdenum and TM oxides precursors and were characterized by different physicochemical techniques.

Experimental and computational data set on adsorption of Cr (VI) from water using an activated carbon.

Chromium (Cr) is a widely used metal in metallurgical and chemical industries, whose waste contaminates the surface and groundwater. Cr (VI) is toxic and produces carcinogenic effects owing to its high mobility in water and soil. In this work, computational and experimental studies from the adsorption of Cr(VI) from aqueous solutions on teak wood residues activated with ZnCl (AT) are presented.

A Comprehensive Picture of the Structures, Energies, and Bonding in [SO(HO)], = 1-6.

Two stochastic methods in conjunction with ab initio computations were used to explore the potential energy surfaces for the microsolvation of SO with up to six explicit water molecules. At least three water molecules are needed to stabilize the Coulomb repulsion that prevents the existence of isolated SO. The formal charge in SO is strong enough to induce water dissociation and subsequent microsolvation of the resulting HSO, OH ionic pair.

Binding and activation of ethylene on tungsten carbide and platinum surfaces.

Density functional calculations were used to evaluate the ability of cubic and hexagonal phases of tungsten carbide to bind ethylene, as a model compound of unsaturated hydrocarbons, since its adsorption is the first step in important catalytic processes. The calculations give the following trend in stability: α-WC(0001)-C > α-WC(0001)-W > Pt(111) > γ-WC(001), with the binding energy varying in the range of -0.72 to -2.

[Clinical impact of ertapenem de-escalation in critically-ill patients with Enterobacteriaceae infections].

Background: Ertapenem has proven to be effective for extended-spectrum beta-lactamases-producing Enterobacteriaceae but lacks activity against non-fermenters; de-escalation to this antibiotic may reduce the selection of resistance to Pseudomonas aeruginosa and improve clinical outcomes.

Aim: To evaluate the clinical impact of de-escalation from broad-spectrum anti-pseudomonal agents to ertapenem, a non-pseudomonal antibiotics for Enterobacteriaceae infections in critically-ill patients.

Methods: We conducted a prospective cohort study in adult patients admitted to intensive care units (ICUs) who had Enterobacteriaceae infections and were de-escalated from empiric anti-pseudomonal coverage to non-pseudomonal antibiotics.

Microsolvation of F.

A staggering structural diversity for the microsolvation of F- with up to six water molecules is uncovered in this work. Given the structural variety and the proximity in energy among several local minima, we show here that in order to match available experimental data, statistical averages over contributing structures are needed, rather than assigning experimental values to isolated structures. Our results suggest that the formal charge in F- is strong enough as to induce partial and total dissociation of water molecules and to alter the nature of the surrounding network of water to water hydrogen bonds.

Adsorption of Nitrate and Bicarbonate on Fe-(Hydr)oxide.

In this work, we used density functional theory calculations to study the resulting complexes of adsorption and of inner- and outer-sphere adsorption-like of bicarbonate and nitrate over Fe-(hydr)oxide surfaces using acidic, neutral, and basic simulated pH conditions. High-spin states that follow the 5N + 1 (N is the number of Fe atoms, each having five unpaired electrons) rule are preferred. Monodentate mononuclear (MM) surface complexes are shown to lead to the most favorable thermodynamic adsorption for both bicarbonate and nitrate with -63.