Search Results (2,479)

Numerous construction enterprises have insufficient efficiency in resource utilization for construction and demolition waste (CDW), restricting global circular economic development. How to improve resource utilization has become an urgent problem. While existing studies have extensively explored operational decisions in CDW resource supply chains, insufficient attention has been given to construction enterprises’ information misreporting and its interaction with on-site conversion efficiency. This paper aims to elucidate the mechanism of action of misreporting and systematically analyzes its effects on the pricing decisions of the CDW supply chain. Drawing on information misreporting theory, this study constructs a Stackelberg game model involving construction firms and recycled building materials manufacturers, and compares supply chain decision-making behaviors under two scenarios: information misreporting and honest disclosure. The main conclusions are as follows: (1) misreporting alters recycled building material pricing and profit distribution by affecting manufacturers’ supply capacity expectations; (2) higher on-site conversion efficiency enhances CDW treatment ability and affects stakeholders’ profits; and (3) misreporting is related to on-site conversion efficiency and onsite conversion costs—enterprises prefer misreporting for short-term gains under low on-site conversion efficiency or high costs, while higher on-site conversion efficiency makes truthful disclosure conducive to long-term stable returns. This paper reveals the CDW supply chain decision-making mechanism from enterprises’ perspective, providing a new theoretical basis and practical value for CDW utilization and supply chain optimization. Full article

Despite increasing policy and industry focus on repairability, consumer repair behavior remains limited. This study examines this contradiction by analyzing user perceptions of repairable products through a survey-based approach (N = 68), focusing on behavioral, economic, and functional drivers of repair decisions. The results reveal a pronounced repairability paradox: while over two-thirds of respondents are willing to pay more for repairable products and strongly support extended product lifecycles, actual repair decisions are constrained by cost, time, and perceived difficulty. Durability concerns significantly reduce acceptance of recycled materials, highlighting the importance of performance trust in sustainable consumption. Additionally, while informational awareness strengthens long-term repair intentions, it does not significantly influence immediate purchasing behavior. This challenges the current focus on Design for Repair as a standalone strategy and underscores the need to integrate repairability with durability, cost-efficiency, and ease of use. By linking empirical data with behavioral and economic theory, this study provides actionable insights for designers, manufacturers, and policymakers seeking to promote more effective and realistic circular economy solutions. Full article

This study investigates asymmetric consumer responses to recycled thermoplastics, with a focus on the roles of eco-consciousness, sustainability knowledge, perceived concerns, trust, and value congruence. Using survey data from Hungarian consumers, the study applies linear and binary logistic regression analyses to examine how these factors influence brand perception, willingness to pay, and communication preferences. The results show that economic concerns act as a dominant barrier, significantly reducing both brand evaluations and willingness to pay, while functional concerns play a more limited role. Trust in sustainability communication and positive brand perception emerge as strong predictors of willingness to pay, with brand perception showing a stronger effect. Eco-consciousness consistently influences consumer responses, whereas sustainability knowledge demonstrates more selective and context-dependent effects. In addition, consumers show a clear preference for credible, evidence-based communication, while informal and promotional signals are less effective. Overall, the findings highlight the importance of reducing perceived risk, strengthening brand perception, and aligning sustainability communication with consumer expectations to support the adoption of recycled thermoplastics in the automotive industry. Full article

Large-scale drinking water treatment plants contribute to environmental burdens through energy consumption, chemical use, and sludge generation. However, Life Cycle Assessment applications to full-scale drinking water treatment plants remain limited in Morocco and other Global South contexts, where site-specific operational data are often scarce. This study assesses the environmental performance of an existing conventional drinking water treatment plant in Al-Hoceima, northern Morocco, using full-scale operational data and a Life Cycle Assessment (LCA) approach based on the ISO 14040/14044 framework. The assessment was performed using OpenLCA v1.11 and the ReCiPe 2016 Midpoint (H) method, with a functional unit of 1 m³ of treated drinking water. The results show that the operational phase dominates the environmental impacts, mainly due to sludge generation and electricity consumption. Two improvement scenarios were therefore evaluated: sludge recycling and the integration of a hydroelectric turbine as an on-site renewable energy option. Both scenarios showed potential to reduce environmental impacts while improving resource efficiency and long-term economic performance. By integrating environmental and techno-economic analyses, this study provides a practical decision-support framework for the sustainable transformation of conventional drinking water treatment plants in Morocco and comparable developing regions. Full article

Extended producer responsibility (EPR) is intended to link producer design decisions to end-of-life costs, but collective EPR schemes typically weaken this link by routing funding through producer responsibility organisations. We develop a multi-level framework of consumer-integrated environmental protection (CIEP) and argue that individual producer responsibility (IPR), where producers bear product-specific end-of-life liability, can function as a governance mechanism that reconnects design, consumer behaviour and waste governance. This paper is a qualitative multiple-case research study—not a systematic review—which draws on three funded research projects: (i) small and medium-sized enterprise (SME) tools for design-for-recyclability, (ii) an artificial intelligence (AI) application for household waste sorting, and (iii) closed-loop recycling of fishing gear in Vietnam. Within the first project (ToCoReRaM), a PRISMA-based systematic review of web-accessible circular economy tools finds that only 2 of 23 tools are SME-accessible through standard web searches. The AI-based waste-sorting application achieves approximately 75% classification accuracy under real-world conditions. The fishing gear study demonstrates technical and economic viability of closed-loop recycling, and a survey of more than 1500 Vietnamese fishers finds 95.8% willingness to return used gear given appropriate incentives. Together, the cases show that effective circular governance requires four complementary elements: IPR-based producer accountability, SME-accessible design tools, digital consumer guidance at the point of disposal, and context-sensitive governance capacity. These findings inform policy pathways for Sustainable Development Goal (SDG) 12 and SDG 14. Full article

Anaerobic co-digestion (AcoD) is increasingly applied in sewage-sludge management and organic-waste treatment because it can improve methane recovery, stabilize mixed substrates, and reduce life-cycle greenhouse-gas emissions under appropriate feedstock and operating conditions. However, existing reviews still focus mainly on feedstock types or isolated enhancement measures and less often connect synergistic mechanisms with engineering implementation and carbon outcomes. The specific novelty of this review is to connect functional feedstock classification, mechanism boundaries, engineering controls, and carbon-performance evaluation within one sludge-centered AcoD framework. This review synthesizes recent progress in AcoD of sewage sludge, food waste, livestock manure, crop residues, and industrial organic streams through a chain from feedstock traits to substrate interactions, microbial responses, engineering performance, and carbon benefits. Feedstocks are reorganized by function rather than by waste name, highlighting how carbon-to-nitrogen contrast, buffering capacity, hydrolysis recalcitrance, and inhibitor profiles jointly define synergy potential. Key mechanisms, including C/N balancing, hydrolysis complementarity, inhibitor mitigation, and direct interspecies electron transfer (DIET), are discussed together with their applicability limits. Representative evidence shows methane-yield or methane-production increases of about 41–55% for selected food-waste–manure blends, approximately 45% for rice–straw–pig manure systems after cellulolytic pretreatment, and approximately 16–55% for selected additive strategies; these values are illustrative rather than directly comparable because the underlying studies differ in substrates, baselines, reactor configurations, pretreatment conditions, and operating parameters. The review then translates mechanism into practice through pretreatment, reactor-selection templates, operating windows, additive reinforcement, and artificial-intelligence-assisted monitoring. Representative cases and life-cycle evidence indicate that AcoD can improve methane productivity while lowering greenhouse-gas emissions relative to landfill or mono-digestion pathways when energy substitution and nutrient recycling are credibly counted. Remaining bottlenecks include incomplete kinetic integration, limited DIET quantification, insufficient reporting of quantitative operating ranges and additive dosages, and weak coupling of carbon, economics, and regional feedstock dynamics. The revised review therefore treats AcoD as a sludge-centered mechanism-to-engineering framework and highlights two transferability gaps that require stronger standardization: biodegradation/toxicity testing and local co-substrate logistics. Full article

The rapid expansion of solar photovoltaic (PV) deployment has led to increasing concerns regarding end-of-life module management and the sustainability of material supply chains, where waste volumes are projected to reach 3.3–5.6 million tons by 2045. This study evaluates the environmental and economic impact of advanced photovoltaic recycling in Germany, focusing on high-value material recovery from crystalline silicon modules. A Full Recovery of End-of-Life Photovoltaics (FRELP) pathway is developed, integrating light-pulse delamination and molten salt etching, and a comparative life cycle assessment and economic assessment framework is applied. The results indicate that advanced recycling achieves high recovery rates for silicon, silver, aluminum, copper and low-iron glass, yielding around €1174.88 per ton of panels recycled. Economic analysis shows that manufacturing PV modules from recycled materials reduces costs by approximately 60–77% compared to virgin material production, mainly due to avoided energy-intensive upstream processes. From an environmental perspective, the recycling-based pathway yields net benefits across impact categories, as avoided impacts from primary material extraction outweigh additional burdens associated with recycling. Overall, PV recycling in Europe is shown to be environmentally and economically favorable; however, technological maturity and policy constraints remain key barriers to large-scale implementation and a holistic overall recycling process, indicating the need for targeted policy support. Full article

The algae-based landfill leachate (LL) treatment system has been proved promising for nutrient recycling and biomass production at lab- or small-scale photobioreactors (PBRs). However, many assessment tools such as techno-economic analyses (TEAs) usually utilize parameters from small-scale experiments as input data to predict the potential performance of commercial large-scale or full-scale bioreactors. Reliability of using data from lab-scale for commercial large-scale estimation is still uncertain. This study compared the performance of three photobioreactor systems that differed simultaneously in scale, geometry, light intensity, mixing mode, and aeration: 0.125 L small-scale flask, 1 L medium-scale tubular PBR, and 15 L wall-shaped PBR for real LL treatment. The 1 L medium-scale tubular photobioreactor outperformed the other two systems in biomass growth rate and the rates of nitrogen and phosphorus removal, even though all three systems removed nearly all NH₄-N and PO₄-P (≈100%) within two weeks. Possible reasons for this better performance include stronger illumination, a bubbling aeration mode, the reactor shape (which improves mixing), and higher surface area to volume ratio × light intensity. According to these results, using relatively small-scale flask experimental data for predictive analysis of industrial-scale algal systems could be inadequate. In this study, volumetric optical radiation (VOR) serves as a promising preliminary descriptive indicator to reflect the overall performance of an algal-based treatment system. Full article

Global food production systems are increasingly challenged by population growth, climate change, water scarcity, and environmental degradation, necessitating the adoption of sustainable, resource-efficient food production strategies. Aquaponic systems integrate recirculating aquaculture with hydroponic crop cultivation, enabling nutrient recycling and improved water-use efficiency. Simultaneously, CRISPR/Cas9 genome-editing technology has emerged as a powerful tool for precise genetic improvement of economically important aquaculture traits. This review critically evaluates current progress in CRISPR/Cas9 applications in aquaculture, with emphasis on Nile tilapia (Oreochromis niloticus). Evidence from peer-reviewed studies indicates that targeted modification of genes associated with growth regulation, disease resistance, nutrient metabolism, feed efficiency, and stress tolerance can significantly enhance fish productivity and physiological resilience. Genes involved in hypoxia adaptation and nitrogen metabolism may further improve environmental performance in intensive recirculating systems by reducing ammonia accumulation and enhancing nutrient utilization. However, most genome-editing studies have been conducted under laboratory or conventional aquaculture conditions, with limited information available regarding the long-term performance, ecological interactions, microbial dynamics, and biosafety of genome-edited fish in aquaponic environments. Technical limitations including off-target effects, mosaicism, delivery efficiency, regulatory uncertainty, and public acceptance continue to constrain large-scale implementation. In the short term, CRISPR/Cas9 applications are likely to focus on practical trait enhancement under controlled aquaculture systems, whereas longer-term research may explore fish lines specifically optimized for nutrient cycling, environmental resilience, and integrated aquaponic sustainability. Overall, CRISPR/Cas9-mediated genome editing represents a promising but still emerging strategy for improving sustainable aquaculture and aquaponic food production systems. Full article

Quinoline derivatives constitute a privileged class of nitrogen-containing heterocycles with extensive applications in medicinal chemistry, agrochemicals, materials science, and functional organic materials. Owing to their broad biological and industrial relevance, the development of efficient, selective, and sustainable synthetic methodologies for quinoline construction remains an active area of research. This review provides a comprehensive overview of recent advances in quinoline synthesis, with particular emphasis on catalytic strategies aligned with the principles of green and sustainable chemistry. Classical transformations, including the Friedländer, Skraup, and Povarov reactions, are revisited in the context of modern catalytic developments that improve reaction efficiency, substrate scope, selectivity, and environmental compatibility. Special attention is devoted to homogeneous and heterogeneous catalytic systems based on both platinum-group and earth-abundant transition metals, highlighting the growing importance of borrowing-hydrogen and acceptorless dehydrogenative coupling methodologies. Recent progress in nanocatalysis, photocatalysis, multicomponent reactions, ionic-liquid-mediated transformations, and metal-free protocols is also critically discussed. Furthermore, solvent-free processes, microwave-assisted synthesis, and recyclable catalytic systems are examined as practical approaches toward minimizing waste generation and energy consumption. Mechanistic aspects, catalytic design principles, substrate limitations, and sustainability metrics are evaluated throughout the review to provide a critical perspective on current methodologies. Collectively, the advances summarized herein demonstrate the rapid evolution of quinoline synthesis toward more atom-economical, environmentally benign, and operationally efficient processes, while also identifying future opportunities for the development of next-generation catalytic platforms for quinoline-based heterocycle construction. Full article

In this study, three types of industrial solid waste—granulated blast furnace slag (GBFS), fly ash, and desulfurization gypsum (DG)—are utilized to collaboratively prepare low-carbon cementitious materials. The effects of steam curing temperature, constant temperature time, and fly ash content on the mechanical properties of multi-source solid waste cementitious materials are systematically investigated, and the optimal mix proportion ratio for low-carbon cementitious materials is determined. The results indicate that as steam curing temperature and constant temperature time increase, the compressive strength of the ternary cementitious material generally shows an upward trend, while the fly ash content exhibits a negative correlation. When the steam curing temperature is 70 °C, the constant temperature time is 10 h, the fly ash content is 20%, and the strength can reach 24 MPa, with both its engineering performance and economic benefits meeting the requirements of practical applications. Meanwhile, the steam curing temperature shows a tendency of first decreasing and then increasing shrinkage rate after 28 d, with the lowest shrinkage rate at 70 °C. Extending the constant temperature time can slightly reduce shrinkage, and the addition of 20–30% fly ash can optimize shrinkage performance. Moreover, the TG/DTG and SEM-EDS microscopic testing demonstrates that the ternary system achieves synergistic activation by accelerated mineral dissolution, ion release and enhanced alkalinity under steam curing, which jointly promotes the formation of AFt and C-A-S-H gel to refine microstructure and improve compactness. This study can not only reduce the consumption of cement, but also facilitate the recycling of industrial waste, providing theoretical support for the application of multi-source solid waste low-carbon materials in practical engineering. Full article

Plantar orthoses play an important role in podiatric care, as they help to redistribute plantar loads, improve foot function, and support the treatment of various conditions, including diabetic foot disease. In this context, additive manufacturing has substantially expanded the capacity to produce customized orthoses through digital geometry acquisition, computational design, and controlled fabrication. From a biomimetic and bionic perspective, 3D-printed plantar orthoses can be understood as engineered interfaces that reproduce, support, or modulate key biomechanical functions of the human foot, including load redistribution, shock attenuation, adaptive stiffness, and gait stabilization. Additive manufacturing enables these biological and biomechanical principles to be translated into patient-specific devices through controlled geometry, graded structures, and material selection. Moreover, from a sustainability perspective, recycled polylactic acid (rPLA) has emerged as a material of potential interest for this type of application, not only because of its compatibility with 3D-printing processes but also because it offers the possibility of reusing polymer waste and reducing the consumption of virgin raw materials in devices whose service life may be limited. This review examines the conditional viability of recycled PLA for 3D-printed plantar orthoses by integrating direct clinical evidence on orthotic function with indirect technical evidence from material-level and process-level studies. The reviewed literature indicates that recycled PLA may offer environmental and economic benefits; however, repeated thermomechanical reprocessing may alter viscosity, dimensional consistency, crystallinity, interlayer adhesion, and mechanical reliability. Recent orthosis-focused studies show that extrusion-based technologies can be applied to customized insoles, lattice or internally reinforced structures, multimaterial systems, and emerging smart concepts; however, most of these developments still rely on virgin or ad hoc-designed materials rather than recycled feedstocks. Overall, the available evidence suggests that recycled PLA should not yet be regarded as a direct substitute for virgin PLA in plantar orthoses. At present, the evidence supporting the use of recycled PLA in plantar orthoses is predominantly indirect and technical rather than directly clinical. Its use appears technically promising, but its viability remains conditional and depends on feedstock traceability, control of the manufacturing process, the suitability of material properties for device function, and validation of the orthosis under clinical conditions. Full article

Achieving sustainable development requires decoupling economic growth from fossil fuel dependence—a challenge that places carbon pricing at the intersection of environmental policy, economic efficiency, and social equity. Carbon taxation is widely regarded among economists as the most cost-effective instrument for reducing greenhouse gas emissions, yet the United States has not adopted a federal carbon price. This study examines the macroeconomic and sectoral consequences of a hypothetical federal carbon tax using the Standard GTAPv7 computable general equilibrium model calibrated to GTAP Database version 12 (2023). A tax rate of 27.7% is derived from the Regional Greenhouse Gas Initiative (RGGI) average auction price of USD 12.81/t CO₂ for 2023—the lowest among active U.S. state carbon programs—and applied as a production tax shock to the fossil fuel sector. Simulations at the California (USD 32.93/t CO₂) and Washington state (USD 53.10/t CO₂) prices provide sensitivity bounds. Under the baseline scenario, U.S. real GDP falls by 0.09%, unskilled employment declines by 0.17%, and fossil fuel production and exports contract sharply. Outside the fossil fuel complex, most sectors record output and export gains, and total U.S. net exports improve by 0.33 percentage points. Bilateral GDP spillovers across eighteen trading partners range from −0.17% (South Korea) to −0.01% (Australia), principally through fossil fuel trade exposure. The results demonstrate that a federal carbon tax at the RGGI price can achieve meaningful emissions reduction at a contained macroeconomic cost, supporting the environmental pillar of sustainability. The concentration of adjustment burdens on unskilled workers highlights the social sustainability challenge of ensuring a just transition. The production reallocation from fossil-intensive to non-fossil sectors is consistent with the circular economy framework and contributes to long-run economic sustainability by reducing dependence on finite, non-renewable resources. Revenue recycling, just-transition provisions, and carbon border adjustment are identified as complementary policy instruments essential for aligning carbon taxation with the integrated environmental, economic, and social dimensions of sustainable development. Full article

Residual volatile organic compounds (VOCs) and non-intentionally added substances (NIASs) limit the reuse of post-consumer recycled high-density polyethylene (rHDPE) in high-value applications because they generate persistent odors and may compromise product quality and regulatory acceptance. This work comparatively assesses five deodorization and purification routes for rHDPE: agitation washing, ultrasound-assisted washing, reflux heating, Soxhlet extraction, and dissolution/precipitation, by combining VOC removal performance, material characterization, and techno-economic evaluation. Ultrasound-assisted washing with SDS achieved ~96% total VOC removal, while reflux heating resulted in near-complete removal (~98%), approaching the analytical detection limit. Soxhlet extraction with ethanol reached 94% after 1 h, and the dissolution/precipitation method provided near-complete purification and removed additional impurities, but at the expense of substantially higher process complexity and cost. Mechanical and physicochemical characterization indicated that the evaluated treatments did not appreciably compromise the measured properties of the recycled polymer. In addition, equilibrium screening with representative analytes in ethanol provided qualitative support for the solvent–polymer interaction discussion. A plant-scale techno-economic assessment identified ultrasound-assisted SDS washing as the most attractive option, offering the best balance between deodorization efficiency, process simplicity, and cost. Overall, the results provide a practical basis for selecting scalable decontamination strategies to upgrade rHDPE quality and expand its use in circular plastic applications. Full article

Wind turbine blade (WTB) end-of-life waste is projected to increase significantly, yet no sustainable recycling solution with a clear energy, economic, and environmental (3E) assessment exists. This paper presents a validated 3E model of a WTB thermal recycling pilot (1 t/day) to benchmark recycled glass fibre (rGF) against virgin glass fibre (vGF) and identifies the throughput at which rGF becomes competitive. This subsequently leads to a projection of 3E performance at 5000 t/y plant capacity, at which rGF achieves approximately 46% lower specific primary thermal energy, 92% of the CO₂ emissions of vGF, and a selling price of 80% of vGF for a financial break-even. Building on this baseline, a novel combined material, heat, and power system is proposed and simulated, integrating the WTB recycling pilot with a 20 kWₑₗ/130 kWₜₕ organic Rankine cycle to serve residential buildings. Results show that coupling the pilot with 3000 m² of apartments yields a near net-zero CO₂ and energy-cost residential complex, with overall CO₂ emissions falling below those of standalone residential buildings combined with vGF production when more than 25 apartments are integrated. Full article