Chemosphere最新文献

Numerous studies reveal pollutants like clindamycin (CLD) in the environment, posing environmental and health risks. Conventional water treatment methods are ineffective at removing these contaminants, typically found in low concentrations. An innovative treatment approach is introduced through pre-concentration via adsorption, which is highly efficient, energy-saving, and reusable. The innovation uses solvents like methanol or ethanol to desorb pollutants, creating concentrated CLD solutions for more effective electrochemical degradation than conventional methods. Thus, this study explores, for the first time, the behavior of CLD electro-oxidation in different media-water, methanol, and ethanol-using a Dimensionally Stable Anode (DSA®-Cl₂). The study reveals distinct degradation mechanisms and offers new insights into solvent-assisted electrochemical treatments. After 30 min of electrolysis, all the current densities evaluated promoted significant degradation, ranging from 90 to 92%. The energy consumption was 2.9 Wh m⁻³ per percentage point at current densities of 2 and 3.5 mA cm⁻². This demonstrates that using higher current densities over shorter electrolysis times is feasible, achieving removal rates of approximately 90%.The performance of chloride-based electrolytes was superior to that of sulfate-based electrolytes due to the ability of DSA®-Cl₂ electrodes to generate reactive chlorine species more efficiently. A higher concentration of supporting electrolytes initially improved CLD removal, but no significant changes were observed after 1 h. Neutral pH conditions optimized CLD degradation, achieving up to 91% removal. Higher pollutant concentrations were associated with lower kinetic constants and decreased removal percentages. Methanol and ethanol enhanced removal rates to 98.3% and 92.3%, respectively, by generating oxidizing species such as methoxy, hydroxymethyl, and ethoxy radicals. The degradation by-products differed across the three media, with each solvent exhibiting distinct oxidation mechanisms. These findings highlight the potential of using methanol or ethanol as an electrolytic medium with efficiency comparable to water.

Developing cost-effective, readily available materials for efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water splitting is a crucial step toward enhancing the profitability and sustainability of energy conversion systems. This research introduces a novel synthesis method for NiFeP/NPC OHs from banana peel bio-waste, a method that could revolutionize the field of materials science and electrochemistry. The use of metallic phosphides, known for their excellent electrical conductivity and catalytic activity, as bifunctional catalysts, combined with the efficient synthesis of nanoporous carbons (NPC) from banana peel bio-waste (BPW), could pave the way for a new era of sustainable and cost-effective energy conversion. By chemically activating different porogens, such as nickel, iron, and phosphorus (NiFeP), to form (oxy) hydroxides (OHs), functional carbonaceous structures with a high density of pores and large specific surface areas can be achieved. The resulting materials, designated as NiFeP/NPC OHs, are characterized by their remarkable porosity, high conductivity, large surface area, and chemical stability. These properties make NiFeP/NPC OHs particularly suitable for electrocatalysis, where they exhibit outstanding activity in both HER and OER. The optimized NiFeP/NPC OHs material shows a very low overpotential of 93 mV for HER and 243 mV for OER at 10 mA cm⁻² and high durability over 100 h. Moreover, the bifunctional NiFeP/NPC OHs electrode demonstrates exceptional catalytic activity and stability in alkaline solutions. This study not only highlights the innovative synthesis of NPC from BPW and the cost-effective fabrication of NiFeP/NPC OHs but also sparks curiosity about the potential of this novel synthesis method.

The issues related to the spread of antibiotics and antibiotic resistance genes (ARGs) have garnered significant attention from researchers and governments. The production of antibiotics can lead to the emission of high-concentration pharmaceutical wastewater, which contains antibiotic residues and various other pollutants. This review compiles the classification and characteristics of antibiotic pharmaceutical wastewater (APWW), offers an overview of the development, advantages, and disadvantages of diverse harmless treatment processes, and presents a strategy for selecting appropriate treatment approaches. Biological treatment remains the predominant approach for treating APWW. In addition, several alternative methods can be employed to address the challenges associated with APWW treatment. On the other hand, the present safety assessment of the effluent resulting from APWW treatment is inadequate, necessitating more comprehensive research in this domain. It is recommended that researches in this area consider the issue of toxicity and antibiotic resistance as well. The PNEC^R model (similar to ecotoxicological PNECs but used to specifically refer to endpoints related to antimicrobial resistance) (Murray et al., 2024) is an emerging tool used for evaluating the antimicrobial resistance (AMR) issue. This model is, characterized by its simplicity and effectiveness, is a promising tool for assessing the safety of treated APWW.

This study investigates the effects of food waste biochar (FWB) on the biological properties of soil, including the microbial community structure, enzyme activities, lettuce growth, and earthworm ecotoxicity. This holistic assessment of various soil organisms was used to assess the potential of FWB as a soil amendment strategy. Pot experiments were carried out over a 28-d period using various FWB concentrations in soil (0-3% w/w). The presence of FWB enhanced the activity of alkaline phosphatase and beta-glucosidase in proportion to the FWB concentration. Similarly, the dehydrogenase activity after 28 d was positively correlated with the FWB concentration. Notably, the application of FWB improved the bacterial diversity in the soil, particularly among hydrocarbonoclastic bacteria, while also prompting a shift in the fungal community structure at the class level. Measures of lettuce growth, including total fresh weight, shoot length, and leaf number, also generally improved with the addition of FWB, particularly at higher concentrations. Importantly, FWB did not adversely affect the survival or weight of earthworms. Collectively, these findings suggest that FWB can enhance soil microbial enzyme activity and support plant growth-promoting rhizobacteria, potentially leading to increased crop yields. This highlights the potential of FWB as an eco-friendly soil amendment strategy.

Per- and polyfluoroalkyl substances (PFAS) are industrial chemicals encompassing thousands of compounds. Due to their persistent, bioaccumulative and toxic character, PFAS have become environmental contaminants, and exposure to these chemicals may lead to adverse health effects. This study aimed to provide a sensitive analytical method for the quantification of 25 PFAS in food including food for the young population and beverages, and to gather the missing occurrence data for the dietary exposure evaluation for the Belgian population. More than a decade ago, such assessment was performed only for PFOS and PFOA and is currently outdated. For the determination of PFAS in foodstuffs, an extraction based on a "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) protocol and combined with a two-step purification using solid-phase extraction (SPE) was optimised. The quantitative analysis was performed by liquid chromatography high-resolution mass spectrometry (LC-HRMS). The method was validated, and the achieved limits of quantification (LOQs) ranged from 0.002 to 0.3 μg/kg, with the exception of HFPO-DA (1 μg/kg). The LC-HRMS analysis of 268 food products from the Belgian market demonstrated that 43% of samples contained at least one PFAS with a maximum of eleven PFAS measured in a stew of wild pork. PFOS was the most detected compound found in 19% of samples, followed by PFBA (18%) and PFOA (15%), while PFTeDA, PFPeS, PFHpS, PFDS, PFUnDS, PFDoDS, PFTrDS, Minor F53B and HFPO-DA were not detected. The concentrations of the different PFAS in commercial food varied from

Sulfur dioxide (SO₂), produced mainly from the combustion of coal, is the most important cause of acidic rain, skin diseases, and environmental issues. To overcome the environmental problems, SO₂ must be captured on an industrial scale before it is released into the air. In chemical industries, organic solvents are used for partial absorption of SO₂. However, those organic solvents have negative environmental effects. Thus, proposing environmentally friendly and green solvents for SO₂ absorption is vital for industries. Recently, increased attention has been paid to capturing SO₂ using Deep Eutectic Solvents (DESs) as the most recently introduced category of green solvents. This study performed a comprehensive screening study on the investigation of the performance of various simple and complicated models for SO₂ solubilities in a wide range of different nature DESs. For this purpose, the most updated and largest SO₂ solubility data bank in DESs involving 976 data points for 63 different nature DESs over wide temperature and pressure ranges has been gathered from open literature. For model screening, for the physical absorption models, the performances of SRK and CPA as the simple cubic and complicated sophisticated equations of state, NRTL and UNIQUAC as the well-known activity coefficient models, and for the chemical absorption models, RETM were investigated and compared. For physical absorption models, coupling an equation of state with the UNIQUAC activity coefficient model i.e. CPA-UNIQUAC, SRK-UNIQUAC, and also using simple SRK-SRK models led to the best performances. Compared to all investigated models, RETM as the chemical absorption model showed the best performance with the AARD% value of 12.95. This shows the importance of considering the chemical absorption mechanism for SO₂ absorption by DESs. Finally, general guidelines for using different modeling approaches were proposed to be considered by the researchers.

In this study, the adsorption capacity of bio-hydroxyapatite (Bio-HAp) from devilfish for the removal of F^- and Cd(II) from aqueous solutions was investigated. This material was synthesized according to a 2FI factorial experimental design by varying the extraction conditions for Bio-HAp, including the type of pretreatment (alkaline and peroxide), the calcination temperature from 550 to 850 °C, and the sonication process. The maximum adsorption capacities were 8.48 and 83.56 mg g^-1 for F^- and Cd(II), respectively. Statistical analysis showed the importance of the type of pretreatment, temperature, and sonication for adsorption. The predicted optimal conditions were Bio-HAp extracted from bone with peroxide pretreatment, calcination at 550 °C and sonication. The surface of the Bio-HAp was found to be mesoporous and basic in character. TGA, FT-IR and SEM-EDS characterizations confirmed the presence of F^- and Cd(II) on the Bio-HAp surface and confirmed the adsorption mechanisms by electrostatic forces, ion exchange, and chemisorption. The Praunitz-Rake model of adsorption isotherm showed better agreement with the equilibrium adsorption data of F^- and Cd(II) at pH 7. Furthermore, photodegradation experiments showed 100% degradation methylene blue (MB) under natural sunlight. This study indicates an effective photodegradation process, suggesting high adsorption capacity of the samples. The use of devilfish as an adsorbent promises to be a viable and sustainable option for the removal of fluoride and cadmium from water, and for use in photodegradation experiments.

The management of reverse osmosis (RO) concentrate remains a challenging task for operators of Landfill Leachates Treatment Plants. In this article we suggest an integrated treatment scheme for RO concentrate that combines solar distillation, struvite precipitation to reduce ammonia content of the distillate and biological treatment of the supernatant either with mixed cultures of bacteria or with microalgae. Experiments in a pilot-scale solar still, equipped with underfloor heating system, showed that the production rate of the distillate ranged up to 3.17 L/d m². The distillate was characterized by elevated average concentrations of ammonium nitrogen; 2028 mg/L and 1358 mg/L in the two experiments conducted, respectively. A decreasing trend on concentrations of NH₄⁺-N was noticed during these experiments, while the opposite was observed for COD. Struvite recovery experiments showed that the optimum Mg:NH₄:PO₃ ratio was that of 2:1:5.8. Under these conditions, the NH₄⁺-N removal reached 88%. Further treatment of the process supernatant into a 4-L hybrid sequencing batch reactor with biocarriers and activated sludge achieved NH₄⁺-N removal higher than 98% in Phases C and D, where 450 and 600 mL of supernatant were added, respectively. Similar removal was also observed in a 2-L bioreactor with microalgae Chlorella sorokiniana when 150 mL of struvite supernatant were added (Phase B) while further increase of the amount of added supernatant to 200 mL resulted to a sharp stop of NH₄⁺-N consumption (Phase C). Calculations for a landfill serving 20,000 inhabitants and a daily RO concentrate production of 6 m³/d showed that the required area for the construction of the solar still was 1893 m² and the volumes of the hybrid and the microalgae reactor were 54 m³ and 60 m³, respectively. The recovered solid material of struvite process, after characterization for heavy metals and organic micropollutants, could be reused to the fertilizers industry.