Search Results (228)

With global plastic production creating immense environmental pressure and conventional recycling methods facing limitations, advanced chemical recycling techniques are crucial. This paper presents details of the design, construction, and operation of two fluidized reactors: a laboratory-scale (LS) reactor and a large-scale laboratory reactor (LSLR) for the catalytic pyrolysis of mixed plastic waste. A waste stream simulating municipal collection, consisting of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polystyrene (PS), was processed using a custom Ni/γ-Al₂O₃ catalyst and an industrial G-0110 catalyst in a two-stage system. The large-scale reactor demonstrated high efficiency, achieving a 90% yield of valuable pyrolysis oil and waxes, a 2% yield of syngas, and an 8% yield of solid residue containing mainly carbon at operating temperatures between 400 and 453 °C. The resulting liquid and wax fractions contained a rich mixture of aliphatic and aromatic hydrocarbons (such as styrene, indene, benzoic acid, toluene, and cumene), confirming their potential as a feedstock for the chemical industry. These results establish that two-stage catalytic pyrolysis in a fluidized bed reactor is a highly effective and promising technology for upcycling mixed plastic waste into valuable resources. Full article

This study evaluates the efficiency of several urban wastewater treatment configurations in reducing suspended solids (TSSs) and organic pollutants (BOD₅ and COD) under Montenegrin conditions. The systems tested include combinations of primary treatment and vertical-flow constructed wetlands (VFCWs) in three different configurations (VFCW1–VFCW3), with and without the addition of low doses of effective microorganisms (EMs). The results show that the inclusion of EMs significantly improves pollutant removal efficiency and system stability. Suspended solid removal reached over 90%, while organic matter removal was also high. Among the evaluated systems, those integrating microorganisms and optimized substrates required the smallest land area to achieve high treatment performance, with some configurations reducing land demand by over 70% compared to traditional systems. Under Montenegrin climatic conditions, the smallest required wetland area to achieve 95% BOD₅ removal was only 1.07 m²/PE in the PT-EM-VFCW3 system (primary treatment + effective microorganisms + vertical-flow constructed wetland configuration 3), which is comparable to or even more favorable than the best values reported in the literature. These findings suggest that enhanced wetland systems offer a sustainable and space-efficient solution for municipal wastewater treatment in areas with land constraints, such as Montenegro. Beyond treatment performance, the results highlight land-use reduction as the dominant economic benefit of the proposed configurations, while the integration of effective microorganisms provides additional operational flexibility under seasonal and variable loading conditions. Full article

Powder Injection Molding (PIM) is a versatile manufacturing technology widely used for fabricating components with complex geometries from metals and ceramics, yet its application to high-performance thermoplastics remains underutilized. This study explores the feasibility of manufacturing products from Polyphenylene Sulfide (PPS)—a promising linear aromatic polymer synthesized in powder form—using PIM technology and investigates the development of PE-based feedstocks with PPS and solid fillers. Regarding the matrix formulation, it was found that using pure paraffin as a binder limited the maximum PPS content to 20%. Consequently, a modified binder system consisting of Low-Density Polyethylene (LDPE) and paraffin in a 70:30 wt.% ratio was utilized, which successfully increased the PPS loading in the feedstock to 50% and enabled stable molding. Following matrix optimization, the study examined composites incorporating various fillers, including chalk, talc, and carbon fibers. Systematic rheological analysis confirmed that these composite suspensions possess characteristics necessary for molding products with complex geometries. Key results indicate that optimal sintering conditions were established to achieve the required mechanical properties. Among the tested fillers, carbon fibers were the most effective reinforcement, increasing the elastic modulus by 33% and flexural strength by 20%. Representative examples of samples successfully manufactured via this approach are presented. Full article

This study examined the impact of various treatments on the storage quality of sugar-cored ‘Fuji’ apples, with the objective of establishing a theoretical foundation for extending the retention period of these apples and augmenting their commercial worth. This experiment utilized three distinct treatments for sugar-cored ‘Fuji’ apples, with the combination of 1-methylcyclopropene and polyethylene self-sealing bag treatment (1-M+PE) demonstrating the most effective prolongation of the storage duration for the sugar-cored apples. The 1-M+PE treatment significantly mitigated the reduction of sugar-cored in ‘Fuji’ apples and extended the onset of cellular rupture, postponing the loss of firmness and preserving the concentrations of sorbitol and sucrose throughout the storage duration. The 1-M+PE treatment effectively prolonged the storage duration of sugar-cored apples in cold storage. ‘Fuji’ apples subjected to 1-M+PE treatment were stored in cold storage for 120 days. The sugar-cored apple rate was 38.9%. The firmness was 14.8% greater than that of the control group. The soluble solid concentration in the sugar-cored part was 3.83% higher than that of the control group. The reducing sugar content in the sugar-cored part was 16.2% higher than that of the control group, and the titratable acid content in the sugar-cored part was 1.86 times greater than that of the control group. The correlation study of the indicators during the storage period revealed a robust association between the rate of sugar-cored apple and the content of sorbitol, potassium, phosphorus, and calcium. Experimental findings demonstrate that the concurrent application of 1-M+PE significantly inhibits the disappearance of sugar-cored. Full article

Penile cancer (PeCa) is a rare malignancy with few validated tissue biomarkers to guide prognosis and treatment, despite growing evidence for a key role of inflammation in its biology. This retrospective study evaluated whether the immuno-expression of selected pro-inflammatory cytokines is associated with disease progression and cancer-specific survival (CSS) in PeCa. Immunohistochemistry (IHC) analysis of eight cytokines (IL-1A, IL-1B, IL-2, IL-6, IL-12, TGF-β1, TNF-α and IFN-γ) was performed in paired tumour tissues and corresponding negative surgical margins from 94 patients with penile squamous cell carcinoma. Compared with surgical margins, tumour tissues showed a characteristic inflammatory shift, with markedly increased IL-1β and IL-6 and relatively reduced TNF-α, IFN-γ, IL-12 and IL-2. Receiver Operating Characteristic (ROC) analysis indicated that TNF-α, IL-6 and IL-12 had the strongest ability to discriminate tumour from normal tissue and provided data-driven cut-offs for subsequent analyses. Within tumour samples, high IL-1α, IL-12 and TGF-β1 immuno-expression was significantly associated with advanced UICC TNM prognostic stage and lymph node involvement. Importantly, in contrast to the classically anti-tumour role of IL-12 described in many other solid cancers, increased IL-12 immuno-expression in tumour tissues in our cohort was independently associated with poorer CSS in multivariable Cox regression (HR 2.42, 95% CI: 1.08–5.41, p = 0.031), alongside advanced TNM stage (HR 5.03, 95% CI: 2.12–11.95, p = 0.0002). These findings highlight IL-1α, IL-12 and TGF-β1 as promising tissue biomarkers of aggressive PeCa and support a central role for cytokine-driven immune dysregulation in penile cancer. The prognostic value of IL-12 should be considered exploratory and warrants validation in larger, multicentre cohorts. Full article

On the road to developing more sustainable and cost-efficient carbon fibres (CFs), replacing the conventional polyacrylonitrile (PAN) precursor with polyethylene (PE) is a promising alternative. Yet most PE-CF studies focus on fibre properties at laboratory or pilot scale and largely overlook scalability—especially in melt-spinning, where precursor filament counts have typically been limited to 32–100, far below industrial CF tows (1000–48,000). This study addresses that gap by (i) modifying a staple-fibre melt-spinning line (MSFP) to directly produce a 10,000-filament PE precursor and (ii) demonstrating inline filament merging on an industrial yarn (IDY) plant at Institut für Textiltechnik (ITA) as a pragmatic scale-up route. Direct 10 k spinning proved technically feasible but did not meet convertibility targets owing to inhomogeneous extrusion and quench: the MSFP precursor showed 18.1 ± 2.0 µm filament diameter, 21.9 ± 3.8 cN/tex tenacity and 130.8 ± 40.8% elongation (total solid draw ratio 2.02). In contrast, the IDY route delivered a fine and uniform precursor with a 9.43 ± 0.02 µm filament diameter, 38.42 ± 0.43 cN/tex tenacity, 15.91 ± 0.76% elongation, and 15.32 ± 1.16% shrinkage at 120 °C (total solid draw ratio 4.55). After discontinuous sulfonation, TGA indicated superior cross-linking of the IDY precursor (≈15% mass loss at 400–600 °C) versus MSFP (≈18%). Inline merging doubled filament count inline and small-scale plying enabled a 6 k tow. Transferring the IDY precursor into continuous sulfonation and carbonisation yielded PE-based CF with a filament diameter < 8.5 µm, tensile strength up to 2.0 GPa, tensile modulus up to 170 GPa, and elongation at break up to 1.75%, without surface defects. The results establish a clear scale-up roadmap: prioritise homogeneous fine-filament extrusion at low throughputs, co-develop segmented quench, and use a stepwise strategy (1–2 k filaments → inline merging → ≥6 k) to enable industrially relevant, cost-effective PE-based CF production. Full article

The spatial configuration of Waste-to-Energy infrastructure plays a decisive role in determining the environmental and economic performance of municipal solid waste (MSW) management systems. This study applies a Life Cycle Assessment methodology to evaluate the environmental implications of centralized and decentralized siting strategies for Refuse-Derived Fuel utilization in Greece. Two alternative scenarios were modeled: (i) a centralized approach based on six large WtE plants as proposed by the Greek Ministry of Environment and Energy (gr. YPEN), and (ii) a decentralized approach involving smaller, regionally distributed units located closer to Recycling and Recovery Facilities. Using the SimaPro software and the ReCiPe method, environmental impacts were quantified across categories including global warming potential, acidification, eutrophication, and particulate matter formation. The results indicate that the decentralized scenario yields substantial environmental advantages, with reductions ranging from 33% to 45% across all impact categories and displaying a 35% decrease in CO₂-equivalent emissions compared to the centralized scenario. Economic analysis confirms these findings, showing a 31% reduction in total transport and emissions-related costs due primarily to minimized long-distance and maritime transport. The study concludes that decentralized RDF-to-energy systems offer a more balanced and sustainable pathway, enhancing operational flexibility, lowering environmental burdens, and improving social acceptance. These results underscore the importance of integrating spatial and logistical parameters in national WtE planning to align with EU waste hierarchy principles and circular economy objectives. Full article

Microplastics (MPs) are increasingly recognized as emerging contaminants in aquatic environments; however, their occurrence and fate in tropical wastewater treatment systems remain poorly understood. This study provides the first inland–island comparison of MP removal in wastewater treatment plants (WWTPs) across Thailand’s Eastern Economic Corridor. Influent and effluent samples were collected from six WWTPs, encompassing five treatment types: oxidation ditch, aerated lagoon, stabilization pond, aerated tank, and sand filtration combined with reverse osmosis. Polymeric composition and size distribution were examined in parallel with conventional water quality indicators. Across all sites, polyethylene (PE) and polypropylene dominated influent MPs, together accounting for 57–92% of total abundance. Inland plants received heterogeneous municipal wastewater, including domestic inputs and agricultural runoff. In contrast, island facilities consistently showed PE-enriched influents (45–60%) in site F, reflecting tourism-driven reliance on single-use plastics and personal care products. In addition, several minor polymers were identified, including poly (vinyl stearate) (up to 26%), polyamide, polytetrafluoroethylene and ethylene–butyl acrylate, highlighting overlooked pathways of MP entry into WWTPs. Fine MPs (100–300 μm) comprised over two-thirds of influent particles, with stabilization ponds reaching 16,000 MP m⁻³. Removal efficiency ranged from 86.0% to 98.5%. Spearman’s correlation and multiple linear regression analyses revealed strong positive relationships between MPs and both total suspended solids (TSS) and turbidity. Suspended solids parameters emerged as the most reliable predictor of MP abundance (adjusted R² = 0.91, p = 0.001). This finding highlights TSS coupled with turbidity as a practical, cost-effective indicator for monitoring MPs in tropical WWTPs. To achieve greater accuracy, a larger dataset should be built and further analyzed. Full article

Heterogeneous catalysts comprising immobilized nickel(II) complexes bearing a fluorine- or trifluoromethyl-substituted iminopyridine ligand (X_n-C₆H_5–n-N=C (CH₃)-C₅H₅N, X = F or CF₃) in fluorotetrasilicic mica interlayers were prepared by reacting Ni²⁺-exchange fluorotetrasilicic mica with the appropriate ligand. Upon activating the precatalyst with triethylaluminum or triisobutylaluminum, the generated active species showed catalytic activity for ethylene oligomerization, yielding low-molecular-weight polyethylene (PE), ethylene oligomers, and wax-like PE. The oligomer distribution almost agreed with what we expected according to the Schultz–Flory distribution. However, the amount of solid products was much higher than the theoretical value, indicating that at least two active species were formed, i.e., the oligomer and low-molecular-weight PE. The precatalyst with a 2,4-F₂C₆H₃ group on the imino nitrogen atom activated by triethylaluminum showed the highest catalytic activity for ethylene oligomerization (408 g-C₂ g-cat⁻¹ h⁻¹), with selectivities to the liquid and solid products of 51.0% and 11.5%, respectively, with the rest of the product corresponding to wax-like PE. Meanwhile, the highest selectivity to the liquid product (66.7% at 233 g-C₂ g-cat⁻¹ h⁻¹) was obtained using the precatalyst with a 2-FPh group on the imino nitrogen atom activated by triisobutylaluminum. Full article

Biodegradable Pickering emulsions are attracting increased appeal owing to their promising and diversifying therapeutic applications. In this study, for the first time, a novel therapeutic Pickering emulsion stabilized with ginger powder (GA4) was formulated, characterized, and tested for doxorubicin (DOX) delivery. GA4_Pes physicochemical characterization by DLS (Dynamic Light Scattering), POM (Polarized Optical Microscopy), Cryo-SEM (Cryo-Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), and rheology testing confirmed stability for at least one month, solid-like gel properties, and multiple morphology even at a low concentration of stabilizer. In addition, the morphological, dimensional, and rheological properties of some GA4_Pe loaded with DOX (GA4_Pe@DOX) were examined. These formulations were of the w/o/w type, stable for at least 28 days, and showed efficient doxorubicin internalization. A 24 h in vitro release assay displayed a sustained and pH-dependent release, with 30% and 50% chemotherapeutic released at pH 7.4 and 5.6, respectively. Furthermore, in vitro cell viability assessment performed using GA4_Pe showed no toxicity on immortalized 3T3 mouse embryonic fibroblasts but a small significant inhibitory effect on human breast cancer cell line MCF7. Interestingly, the GA4_Pe@DOX emulsion exerted a cytotoxic effect on MCF7 cells very similar to that of the free DOX solution with the same doses of DOX loaded in the same emulsion. Therefore, the total biocompatibility/biodegradability, good drug entrapment, and high stability, as well as the prolonged release and anti-tumor efficacy maintenance of the loaded drug, suggest a feasible application of ginger powder-based Pickering emulsions for topical delivery as a selective therapeutic platform in targeted formulations of antineoplastic drugs. Full article

The increase in municipal solid waste (MSW) generation and its inefficient management have caused significant environmental impacts, particularly in developing countries such as Mexico. In the central region, final disposal in uncontrolled sites (UCSs) remains a common practice despite its negative effects on the environment and public health. These impacts have been underestimated due to the scarcity of studies and the lack of technological alternatives aimed at mitigating them. In response to this problem, Life Cycle Assessment (LCA) emerges as a strategic tool to quantify these effects and to guide decision-making toward more sustainable management. The objective of this study was to evaluate the environmental impacts of a UCS using LCA, considering four scenarios: a baseline (E0) representing the current system conditions and three alternative scenarios (E1, E2, and E3) designed to explore potential improvements in environmental performance and to identify a feasible option under the socioeconomic conditions of a municipality in central Mexico. The functional unit was defined as the treatment of one tonne of MSW. The system boundaries included the separation of recyclable inorganic waste (RIW), the treatment of organic waste (OW) through composting and anaerobic digestion (AD), and the final disposal of mixed waste (MW) in UCSs and sanitary landfills. The assessment was performed using SimaPro Analyst v9.6 software and the ReCiPe methodology. The E0 scenario exhibited the highest environmental burdens, whereas E2 and E3 reduced the disposal of MW from 85.92% to 52.57% and emissions by 78.9%. E3 showed the lowest overall impact by integrating mechanical separation, AD, and controlled landfill disposal. E2, which employed composting instead of AD, proved to be a viable alternative for resource-constrained contexts. The results support the closure of uncontrolled sites and encourage the transition toward integrated systems that incorporate valorization technologies, which are urgently needed to achieve the Sustainable Development Goals. Full article

To enhance the overall performance of asphalt pavements and promote the efficient utilization of solid waste resources, this study innovatively incorporates recycled polyethylene (PE) particles and recycled ethylene-vinyl acetate copolymer (EVA) particles, each compounded with waste cooking oil (WCO), to modify base asphalt. Systematic tests were conducted to evaluate the physical and rheological properties of the composite modified asphalt. Additionally, Fourier transform infrared spectroscopy (FTIR) and thin-layer chromatography with flame ionization detection (TLC-FID) were used to analyze the microstructures and internal components of the modified asphalt. The results indicate that the optimal mixing ratio for the WPA is 5% WCO, 5% EVA, and 5% PE. With the incorporation of these modified materials, the asphalt’s high-temperature and low-temperature properties, as well as its rutting and fatigue resistance, are enhanced to some extent. Furthermore, the modification significantly improves the rheological properties of the asphalt across the full temperature range. Additionally, the modified materials lead to changes in the internal composition of the asphalt: the content of lighter components decreases, while the content of heavier components increases. These changes in the internal composition are the primary cause of the observed improvements in the rheological properties of the asphalt. Full article

The use of ammonia-fueled solid oxide fuel cells (NH3-SOFC) in shipping has emerged as a key area of research for advancing zero-carbon transportation. This study integrates and analyzes a novel ship design powered by NH3-SOFCs to quantify its environmental impact across its entire life-cycle, from production to disposal. A 200 TEU ammonia-fueled container ship operating on the Yangtze River is used as the reference vessel. Comprehensive technical analysis and modeling of the ship’s construction, operation, and Decommissioning stages are conducted. By utilizing life-cycle assessment and the ReCiPe 2016 method for calculations, 19 environmental impact indicators were obtained, weighted, and normalized. Life-cycle characterization results reveal that ecosystem and human health impacts are predominantly influenced by the operation stage. Thus, focusing on environmental protection measures and technological innovations during operation is crucial to mitigate these impacts. Conversely, resource depletion is mainly driven by the construction stage, underscoring the need for optimized design, production processes, and the use of eco-friendly materials to reduce resource consumption. A comparative analysis between diesel-powered and ammonia-powered ships shows that while ammonia SOFC ships have a slightly higher environmental load in terms of metal consumption, diesel-powered ships exhibit higher overall environmental loads in other impact indicators. This demonstrates the superior environmental and social benefits of ammonia SOFC ships compared to traditional diesel power systems. Full article

Microplastics (MPs) represent a persistent class of emerging contaminants, of which significant amounts can be found in sewage sludge. In this study, the effect of hydrothermal carbonization (HTC) temperature on MPs and the properties of digested sewage sludge (DSS) was evaluated. The HTC process was carried out at temperatures of 200, 210, and 220 °C for 2 h in a batch reactor, and the solid products were subjected to (i) mass balance and fuel properties and (ii) microplastic occurrence analysis using Confocal Raman Microspectroscopy and Scanning Electron Microscopy. In digested sludge, 2700 ± 475 MP particles/100 g d.m. were detected, mostly fragments with ~350 ± 100 fibers. Hydrocharcontained only black and brown fragments in the following amounts: 4175 ± 575 (200 °C), 4450 ± 700 (210 °C), and 1450 ± 590 (220 °C), respectively, after 2 h. The microplastic removal rate was 54% for the highest temperature. Polystyrene (PS) was identified in untreated sludge, while only PE was detected after HTC at 200–210 °C, and no MPs were identifiable at 220 °C. The surfaces of post-MPs exhibited progressive degradation with increasing HTC temperature. The results confirm that HTC lowers the content and alters the physicochemical properties of microplastics, reducing their thermal stability and degrading their structure, while simultaneously improving the fuel properties of hydrochars by increasing the calorific value and carbon content. Full article

Micro(nano)plastics are important emerging contaminants and a current research hotspot in the environmental field. Micro(nano)plastics widely exist in various organic wastes such as waste sludge, food waste (FW) and livestock manure and often enter into digesters along with anaerobic digestion (AD) treatment of these wastes, thereby exerting extensive and profound influences on anaerobic process performance. This study reviews sources of micro(nano)plastics and their pathways entering the anaerobic system and summarizes the quantities, sizes, shapes and micromorphology of various micro(nano)plastics in waste sludge, FW, livestock manure, yard waste and municipal solid waste. The current advances on the effects of multiple micro(nano)plastics mainly polyvinyl chloride (PVC), polystyrene (PS) and polyethylene (PE) with different sizes and quantities (or concentrations) on AD of organic wastes in terms of methane production, organic acid degradation and process stability are comprehensively overviewed and mechanisms of micro(nano)plastics affecting AD involved in microbial cells, key enzymes, microbial communities and antibiotic resistance genes are analyzed. Meanwhile, coupling effects of micro(nano)plastics with some typical pollutants such as antibiotics and heavy metals on AD are also reviewed. Due to the extreme complexity of the anaerobic system, current research still lacks full understanding concerning composite influences of different types, sizes and concentrations of micro(nano)plastics on AD under various operating modes. Future research should focus on elucidating mechanisms of micro(nano)plastics affecting organic metabolic pathways and the expression of specific functional genes of microorganisms, exploring the fate and transformation of micro(nano)plastics along waste streams including but not limited to AD, investigating the interaction between micro(nano)plastics and other emerging contaminants (such as perfluorooctanoic acid and perfluorooctane sulphonate) and their coupling effects on anaerobic systems, and developing accurate detection and quantification methods for micro(nano)plastics and technologies for eliminating the negative impacts of micro(nano)plastics on AD. Full article