Mechanochemical Synthesis of Cross-Linked Chitosan and Its Application as Adsorbent for Removal of Per- and Polyfluoroalkyl Substances from Simulated Electroplating Wastewater.

Chitosan is a promising adsorbent for removing a wide range of pollutants from wastewater. However, its practical application is hindered by instability in acidic environments, which significantly impairs its adsorption capacity and limits its utilization in water purification. While cross-linking can enhance the acid stability of chitosan, current solvent-based methods are often costly and environmentally unfriendly.

Adsorption of Cu(II) and Ni(II) from Aqueous Solutions Using Synthesized Alkali-Activated Foamed Zeolite Adsorbent: Isotherm, Kinetic, and Regeneration Study.

Water pollution, particularly from heavy metals, poses a significant threat to global health, necessitating efficient and environmentally friendly removal methods. This study introduces novel zeolite-based adsorbents, specifically alkali-activated foamed zeolite (AAFZ), for the effective adsorption of Cu(II) and Ni(II) ions from aqueous solutions. The adsorbents' capabilities were comprehensively characterized through kinetic and isotherm analyses.

Regeneration of exhausted adsorbents after PFAS adsorption: A critical review.

The adsorption process efficiently removes per- and polyfluoroalkyl substances (PFAS) from water, but managing exhausted adsorbents presents notable environmental and economic challenges. Conventional disposal methods, such as incineration, may reintroduce PFAS into the environment. Therefore, advanced regeneration techniques are imperative to prevent leaching during disposal and enhance sustainability and cost-effectiveness.

Impact of polystyrene microplastics on the growth and photosynthetic efficiency of diatom Chaetoceros neogracile.

The increasing prevalence of microplastic pollution in aquatic environments has raised concerns about its impact on marine life. Among the different types of microplastics, polystyrene microplastics (PSMPs) are one of the most commonly detected in aquatic systems. Chaetoceros neogracile (diatom) is an essential part of the marine food web and plays a critical role in nutrient cycling.

Corrosion by Polythionic Acid in the Oil and Gas Sector: A Brief Overview.

Polythionic acid (PTA) corrosion is a significant challenge in the refinery industry, leading to equipment degradation, safety risks, and costly maintenance. This paper comprehensively investigates the origin, progression, mechanism, and impact of PTA corrosion on various components within refinery operations. Special attention is afforded to the susceptibility of austenitic stainless steels and nickel-based alloys to PTA corrosion and the key factors influencing its occurrence.

Toxicity Effects of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) on Two Green Microalgae Species.

Amongst per- and polyfluoroalkyl substances (PFAS) compounds, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have a high persistence in physicochemical and biological degradation; therefore, the accumulation of PFOS and PFOA can negatively affect aquatic organisms and human health. In this study, two microalgae species ( and ) were exposed to different concentrations of a PFOS and PFOA mixture (0 to 10 mg L). With increases in the contact time (days) and the PFAS concentration (mg L) from 1 to 7, and 0.

Intercalating negatively charged pillars into graphene oxide sheets to enhance sulfonamide pharmaceutical removal from water.

Herein, novel composite materials were prepared by intercalating functional pillars, i.e., pentafluorobenzene (PFB) and sodium 2,3,4,5,6-pentafluorobenzoate (PFBS), into graphene oxide (GO) sheets.

Improved fractal kinetic model to predict mechanochemical destruction rate of organic pollutants.

Mechanochemical destruction of organic pollutants by high energy milling with inorganic reagents is considered a promising non-thermal technology to detoxify hazardous waste. However, due to complex nature of the physicochemical phenomena involved, pollutant destruction kinetics heavily depends on the used reagents and operating parameters, thus varying case by case. In the present work, a fractal model was validated as flexible tool to interpolate pollutant mechanochemical destruction data satisfactorily.

Modelling of hydrogen sulfide fate and emissions in extended aeration sewage treatment plant using TOXCHEM simulations.

Odors due to the emission of hydrogen sulfide (HS) have been a concern in the sewage treatment plants over the last decades. HS fate and emissions from extended aeration activated sludge (EAAS) system in Muharram Aisha-sewage treatment plant (MA-STP) were studied using TOXCHEM model. Sensitivity analysis at different aeration flowrate, HS loading rate, wastewater pH, wastewater temperature and wind speed were studied.

Removal performance and optimisation of pharmaceutical micropollutants from synthetic domestic wastewater by hybrid treatment.

Occurrence of pharmaceutical micropollutants in aquatic environments has been one amongst serious environmental problems. During this study, two reactors, including a sequencing batch reactor (SBR) + powdered composite adsorbent (CA) (first reactor, SBR + CA) and a sequencing batch reactor (second reactor, SBR), were designed to treat synthetic wastewater. Powdered CA was added with a dosage of 4.

Computational investigation of NO adsorption and dissociation on the silicon-embedded graphene catalyst: A density functional theory perspective.

One of the encouraging processes to protect the environment is the catalytic conversion of NO and other harmful greenhouse gases. Employing heteroatom dopants into the Graphene structure for this conversion is an attractive technique owing to its relatively low price and the very low destructive impacts. DFT was applied to explore fundamental and principal reactions of NO adsorption and dissociation over the Silicon-embedded Graphene catalyst to contribute to the search for green catalysts in the conversion of toxic gases into less harmful ones.

Pesticides in aquatic environments and their removal by adsorption methods.

Although pesticides are widely used in agriculture, industry and households, they pose a risk to human health and ecosystems. Based on target organisms, the main types of pesticides are herbicides, insecticides and fungicides, of which herbicides accounted for 46% of the total pesticide usage worldwide. The movement of pesticides into water bodies occurs through run-off, spray drift, leaching, and sub-surface drainage, all of which have negative impacts on aquatic environments and humans.

Technologies for the nitrogen oxides reduction from flue gas: A review.

The required energy of the global industry is mostly generated from fossil fuel sources, such as natural gas, gasoline, diesel, oil, and coal. Nitrogen oxides are one of the main air pollutants that are produced from the combustion of fossil fuels in stationary and mobile sources. Development of new technologies to decrease the NO emission from exhaust gases is essential due to the harmful effect of NO on the environment and human health.

Effect of high energy ball milling on organic pollutant adsorption properties of chitosan.

In the present work, chitosan physicochemical transformations that occur during high energy ball milling are investigated and correlated with adsorption capacity of organic pollutants (using azo-dye reactive red 2 as molecular probe). Experimental results reveal that chitosan ball milled for 1 h shows a 70% increase of adsorption capacity, compared to unmilled one, while longer milling time causes a sensible reduction of such capacity. This trend correlates with specific surface area evolution under milling, thus suggesting the primary role of particle comminution in augmenting chitosan adsorption properties.

Ultrasound-Assisted Preparation of Chitosan/Nano-Activated Carbon Composite Beads Aminated with (3-Aminopropyl)Triethoxysilane for Adsorption of Acetaminophen from Aqueous Solutions.

A composite chitosan/nano-activated carbon (CS-NAC) aminated by (3-aminopropyl)triethoxysilane (APTES) was prepared in the form of beads and applied for the removal of acetaminophen from aqueous solutions. NAC and APTES concentrations were optimized to obtain a suitable adsorbent structure for enhanced removal of the pharmaceutical. The aminated adsorbent (CS-NAC-APTES beads) prepared with 40% / NAC and 2% / APTES showed higher adsorption capacity (407.

Simulation and computer modeling of asphaltene in different solvents on oil-water interfaces using a molecular dynamic methodology.

Molecular dynamics (MD) simulations were used to study the thermodynamic properties of asphalt binder components, namely asphaltene, and other solvents, such as pentane or toluene, before and after adding pentane or toluene. The two systems were compared by MD simulation under lots of molecules, temperature and pressure to predict their internal energy, structure, and density as a function of time or distance between molecules. Then the simulation results of the two systems were analyzed and compared to determine the influence of different solvents on asphaltene aggregation behavior.

Cross-linked chitosan/zeolite as a fixed-bed column for organic micropollutants removal from aqueous solution, optimization with RSM and artificial neural network.

Organic micropollutants (MPs) in low concentrations can affect aquatic ecosystems and human health. Adsorption technique is one of the promising methods to remove MPs. Chitosan and zeolites are environmentally friendly and low-cost adsorbents.

Synthesis and Regeneration of A MXene-Based Pollutant Adsorbent by Mechanochemical Methods.

In the present study, an adsorbent material for removal of organic contaminants in wastewater is synthetized by a green and facile mechanochemical method. It is composed of TiCT MXene layers (obtained by mechanochemical etching of MAX phase with concentrated HF) pillared with terephthalate by rapid direct reaction. Such material shows high specific surface area (135.

New modeling method to simulate asphaltenes at oil sands process in water management.

The study of various structures, physicochemical structures and dynamic characteristics of oil-water interface asphaltenes is an important basis for the large-scale development and efficient clean utilization of oil sands. The molecular dynamics simulations method provides a possibility for revealing the physicochemical structure and dynamic characteristics of oil sands. The emphasis of this paper is to study the physic-chemical structure of tar sands asphaltenes and the changes of their kinetic properties by using molecular dynamics simulations.

Stable Covalent Organic Frameworks as Efficient Adsorbents for High and Selective Removal of an Aryl-Organophosphorus Flame Retardant from Water.

A critical challenge in environmental remediation is the design of adsorbents with proper pore size for the removal of organic pollutants. Three covalent organic frameworks (COFs) with different pore sizes were successfully prepared by a room-temperature solution-suspension method and used to remove a typical aryl-organophosphorus flame retardant [triphenyl phosphate (TPhP)] from aqueous solution. The prepared COFs showed strong acid resistance and thermal stability.