ABSTRACT. Waste management is now beyond just evacuating waste from cities to dumpsites, rather, it now incorporates the transformation of waste to reusable products. This not only supports sustainable resource use; it equally reduces the trend of environmental degradation associated with waste dumping. More broadly, the idea described above is a strategic component of the circular economy theory that incorporates the principle of reduce-reuse-recycle (3R’s). While cities such as Stockholm exhibit features of this principle, those on the African continent such as Lagos, in Nigeria is grappling with sustainable waste management. The question that arises is: what is Stockholm doing that Lagos is not? Answering this question requires a detailed study of waste management practices in the two cities. It is given this background that this study examined prevailing waste management practices in Stockholm and Lagos, with a view to establishing possible points of strategy transfer from Stockholm to Lagos. This study relied on secondary data sourced from the websites of waste management agencies in Stockholm and Lagos (Table 1). Table 1. Secondary data sources from Stockholm and Lagos Cities Data sources Stockholm (Sweden) Stockholm Municipality (https://start.stockholm/en/) Swedish Environmental Protection Agency (https://www.naturvardsverket.se/en/publications/waste/) Statistics Sweden (https://www.scb.se/en/)

Lagos (Nigeria) Lagos State Waste Management Authority (LAWMA) (https://lawma.gov.ng/) Lagos State Environmental Protection Agency (https://lasepa.gov.ng/) National Bureau of Statistics, Nigeria (https://www.nigerianstat.gov.ng/) Our study found that in Stockholm, waste management is characterised with municipal management using the circular economy principle. Also, adequate supporting regulations were sufficiently put in place to regulate waste management in the city. Whereas in Lagos, the responsibility for managing waste lies with the Lagos State Government. This arrangement supported by weak regulatory framework has continued to curtail the extent to which the principles of sustainable waste management could be pursued in the state. Recommendations of this study include the need for Lagos to emulate Stockholm in her waste management practices. This could start from delineating the function of waste management to local governments in the state, providing adequate funding for the use of technology in waste management, create enabling environment for private sector participation in waste management and enacting regulations that strengthens sustainable waste management in the state. Lastly, there is the need for proper sensitisation of the citizens, companied and related waste-generating outfits of the need to imbibe the 3Rs principle of reduce, reuse and recycle in their operations towards the adoption of circular economy theory in the management of waste in the state.

ABSTRACT. The citrus industry generates significant amounts of orange processing waste (OPW) in the form of peels, seeds, and pulp. If not managed properly, such waste has the potential to negatively affect the environment. With the transition to a circular economy, the valorization of OPW through sustainable biotechnological processes has become increasingly crucial. Solid-state fermentation (SSF) offers a process both for the biotreatment and for transformation of OPW into high value-added products. FERONIA addresses these environmental concerns by employing SSF processes with specialized indigenous microbiota. Physicochemical analysis revealed notable changes in the inoculated OPW samples compared to non-inoculated control. Organic matter and organic carbon content decreased substantially in inoculated samples, attributable to efficient microbial degradation of the substrate, and ash content increased proportionally, as expected. TKN content increased during SSF, due to organic matter loss. The activities of exoglucanase, endoglucanase, β-glucosidase and polygalacturonase were strongly prevalent, facilitating efficient degradation of the cellulose, hemicellulose, and pectin fractions of OPW. Total soluble carbohydrate and protein content were also elevated, indicating enhanced breakdown of complex biomolecules, due to high microbial activity. Antioxidant activity was also higher in the inoculated samples compared to the non-inoculated control. The high antioxidant capacity of the SSF product highlights the valorization potential of OPW. Integrated physicochemical and biological data obtained within the FERONIA project confirm that SSF can be effectively used for the sustainable management of OPW, facilitating the transition toward the bioeconomy. Funding Information: The research project entitled “Multipurpose solid state fermentation as an integrated biorefinery approach to valorize orange processing waste for food and animal feed”, acronym “FERONIA” is implemented in the framework of H.F.R.I call “Basic research Financing (Horizontal support of all Sciences)” under the National Recovery and Resilience Plan “Greece 2.0” funded by the European Union –NextGenerationEU (H.F.R.I. Project Number: 014995).

ABSTRACT. Over the last decades numerous different techniques to purify water have been developed for water purification, such as membrane filtration, centrifugation, precipitation, flocculation and reverse osmosis, among many others. However, adsorption is considered the most accessible purification method due its effectiveness, low-cost and the wide range of pollutants it can treat. Initially, activated carbon was used as an adsorbent, but over time it was replaced by other more economical materials. In this sense, Metal-Organic Frameworks (MOFS) are proposed as attractive candidates for the wastewater treatment due to their unique properties which distinguish them from other porous materials. This is thanks to their high porosity and specific surface area, highly tunable structure, simple synthesis and their ease of functionalizing both the surface and pores. However, the main drawback of MOFs is their stability, specifically their limited stability in aqueous media, primarily due to hydrolysis and ligand displacement by water. Interestingly, MOFs can combine with other adsorbent materials as biochars and clays. This could improve their properties such as stability and adsorption capacity. These materials are known as MOF composites (MOFCs) and show a high potential not only for water treatment but also for other applications. A series of MOF and their composites have been synthesized for this purpose. Among them MIL-100 (Fe), MIL-101 (Fe) and MIL-88A. Moreover, corresponding composites of these MOF with Biochar (BC) and clay and alginate have been synthesized.

ABSTRACT. Efficient urban waste management should be based on general principles that ensure collective well-being. In this contribution, we adopt three guiding principles — effectiveness, efficiency and equity — from which three economic sustainability objectives are derived. We analyse the Italian case in the period 2014–2023, with particular attention to the regulatory reform introduced in 2019, representing a discontinuity point. The methodological approach combines β and σ convergence analysis and regression analysis to assess the evolution of performance in terms of separate collection, cost dispersion and the effect of regulation. The results highlight heterogeneous dynamics at the territorial level, suggesting that uniform policies risk being ineffective if not accompanied by targeted interventions.

ABSTRACT. This research will investigate the impact of Industry 4.0 skills and maturity on managers' willingness to implement corporate environmental sustainability practices (CESP) in food supply chains (FSCs). With seizing and monitoring capabilities as moderators, this research will use a mixed method approach. First, qualitative interviews will be conducted followed by application of the Analytical Hierarchy Process (AHP) and Decision-Making Trial and Evaluation Laboratory (DEMATEL). Finally, regression analysis will be used to determine relationships and influence strength in FSC CESP, thus advancing the Industry 4.0-driven sustainable FSC discourse.

ABSTRACT. This paper investigates the application of Circular Economy (CE) strategies in the consumer electronics sector, with a particular focus on the challenges posed by e-commerce and product returns. Given the environmental and logistical burden of returned goods, especially in the health electronics domain, the study aims to reduce electronic waste and improve reverse logistics through CE principles. CE promotes resource efficiency by narrowing, slowing, and closing resource loops, which, in consumer electronics, includes product design for durability, ease of repair, and recyclability. The research addresses three core questions: the current CE strategies in the sector, barriers and trends in their implementation, and how insights from literature can inform data-driven methods to reduce returns. A systematic literature review identifies existing practices and gaps, followed by the use of machine learning and prescriptive analytics to forecast return rates and product life cycles. These approaches are applied in a case study of a large Dutch health electronics company. The study contributes scientifically by proposing a framework for CE adoption supported by data-driven models, and practically by offering insights to improve reverse logistics and sustainability in e-commerce operations.

ABSTRACT. The transition to a sustainable energy system relies heavily on critical raw materials (CRMs) (Pommeret, Ricci, and Schubert 2022), particularly those essential for electric vehicle (EV) applications (Koese et al. 2025; Lehtimäki et al. 2024). However, CRMs supply chains are highly vulnerable to disruptions driven by various factors—such as geopolitical tensions—which lead to significant price volatility. These fluctuations not only undermine the stability of EV supply chains but also generate economic uncertainty for manufacturers and policymakers (Jones, Nguyen-Tien, and Elliott 2023; Riva Sanseverino and Luu 2022). The circular economy (CE) is increasingly regarded as a promising strategy for addressing these CRMs supply challenges (Salim et al. 2022). While existing studies have broadly explored CRMs-related risks, there remains a lack of systematic, data-driven research that analyzes these disruptions using empirical evidence. This study aims to fill that gap by investigating abnormal price movements in the CRMs market, thereby contributing to a deeper understanding of CRMs supply dynamics and the potential integration of CE strategies (Cimprich et al. 2023). Building on this foundation, the research will further examine the financial mechanisms that can support the adoption of CE solutions in the EV sector.

ABSTRACT. The transition toward a Circular Economy (CE) presents opportunities for enhanced resource efficiency, waste valorization, and regional resilience. The Horizon Europe project IS2H4C (Industrial Symbiosis-to-Hubs for Circularity) advances this goal by supporting the development of Hubs for Circularity (H4C), regional ecosystems rooted in Industrial Symbiosis (IS) that promote collaborative resource sharing among firms. Despite their potential, Circular Business Models (CBMs) often face financing barriers due to perceived risks, uncertain returns, and limited data transparency. In response, this study introduces a valuation framework using publicly available financial data from firms involved in IS2H4C. Adopting a stepwise case-study approach, we assess firm-level valuations under two scenarios—"Without Circularity" and "With Circularity"—using Discounted Cash Flow (DCF) modeling combined with machine learning-based forecasting. ESG-related benefits in the circular scenario (e.g., energy savings, emissions reduction) are monetized through incentives and taxes. This incremental valuation—from individual firms to multi-firm IS networks—quantifies added economic value from collaboration and circular practices. Our framework offers actionable insights to investors and banks, addressing information asymmetries and supporting more informed financing decisions for circular ventures, aligned with the objectives of the European Green Deal.

ABSTRACT. Industrial symbiosis fosters collaboration among organizations to optimize resource usage and reduce waste, requiring an efficient and accessible information-sharing system. Cloud computing offers a scalable and cost-effective solution to support this, but selecting a suitable service remains challenging due to the complexity and diversity of cloud offerings. Decision-makers often face difficulties navigating technical details, aligning services with organizational priorities, and making quantitative comparisons.

To address these challenges, this study presents a decision support framework and tool designed to simplify cloud service selection. Using the Analytical Hierarchy Process (AHP), the framework evaluates services based on six key criteria: availability, performance, scalability, reliability, security, and cost-effectiveness. Metrics for these criteria were carefully chosen through a feasibility study, ensuring they are practical and accessible to users.

The framework was developed following the Design Science Research Methodology (DSRM) and implemented as a Microsoft Excel template. The tool allows users to customize criteria weights according to their preferences and includes predefined scenarios, such as performance-focused or cost-sensitive options. Users can input data for multiple cloud services, and the tool calculates scores to provide objective rankings.

To validate the tool, a Technology Acceptance Model (TAM) evaluation involved five experts, who rated its usefulness, ease of use, and likelihood of future adoption. Average scores of 5.7, 5.7, and 5.55 out of 7 confirmed its effectiveness and practicality.

This research offers a structured and automated solution for organizations to select cloud services objectively. By simplifying complex decisions, the framework empowers decision-makers to save time and align choices with organizational goals, while paving the way for similar applications in other multi-criteria evaluation contexts.

ABSTRACT. The European Union’s (EU) ambitious energy transition policies, including the phase-out of internal combustion engines by 2035 under the “Fit-for-55” package, are driving a rapid increase in electric vehicle (EV) adoption. This surge will generate a significant volume of end-of-life (EOL) lithium-ion batteries (LIBs), for which the EU-27 mandates strict recycling targets. However, relying solely on recycling may overlook the potential of alternative circular strategies such as repurposing and remanufacturing. Among these, second-life applications in stationary energy storage offer a promising opportunity to alleviate battery demand pressures while supporting renewable energy integration. This study develops a system dynamics model to assess the flow of LIBs in the EU-27 from 2020 to 2050, accounting for EV adoption, battery degradation, second-life repurposing, and final recycling. The model evaluates different scenarios varying in policy targets, technological development, and demand trends. Preliminary results focus on Germany, France, Italy, and Spain, comparing projected EOL battery volumes with current and planned recycling capacities under two repurposing scenarios (30% and 70%). Findings highlight significant geographical disparities: while Germany and France show alignment between recycling capacity and EOL battery volumes, Spain and Italy face capacity mismatches—potentially mitigated by increasing repurposing rates. The study underscores the need for integrated planning that combines recycling infrastructure development with circular economy strategies, especially in markets at risk of overstocking. The model serves as a decision-support tool for policy and infrastructure planning, identifying timing mismatches and capacity gaps. Future work will extend the model to include endogenous recycling capacity assessment, remanufacturing routes, and the impact of circular practices on raw material supply and environmental outcomes.

ABSTRACT. The advent of Industry 4.0 (I4.0) technologies presents transformative opportunities for manufacturing sectors, particularly in emerging economies striving for sustainability. This study examines the integration of I4.0 technologies to enhance sustainable practices in manufacturing supply chains. Utilizing a mixed-method approach, the research identifies key drivers and barriers influencing I4.0 adoption and assesses their impact on achieving carbon neutrality and supply chain resilience. Findings indicate that environmental factors are the primary drivers. The study underscores the necessity for strategic alignment and robust policy frameworks to facilitate the successful implementation of I4.0 technologies for sustainable manufacturing.​

ABSTRACT. Smart circular economy expands upon circular economy by considering extensively the use of digital technologies to leverage the R-strategies. However, this may create the impression that from a technological perspective only digital technologies need to be considered as enablers of the R-strategies. This perspective fails to consider that R-strategies are also supported by business information systems. The research focuses on the domains of smart remanufacturing and Enterprise Resource Planning (ERP) systems due to their critical role in their respective fields. The main objective of this research is to identify the overlooked connection of both domains and, based on insights from the literature, propose conceptual actions to realize synergies. To this end, a structured literature review was conducted. The analysis reveals that although extant literature recognizes the cross-link between smart remanufacturing and ERP systems on a high level, it does not provide a holistic view on a middle or detailed level. The proposed actions suggest that even if achieving synergies may be complex, it is worth the effort since only the combination of both domains leads to an implementation of smart remanufacturing and circular economy in practical applications.

ABSTRACT. The recent paradigm shift away from automobile-centric urban transportation toward micro-mobility solutions, such as electric scooters and e-bikes, presents substantial potential for enhancing the sustainability of urban mobility systems[1]. Micro-mobility modes exhibit considerable advantages in terms of seamless integration with existing public transportation networks, thereby significantly improving accessibility and convenience for short- to medium-distance trips within densely populated metropolitan areas[2]. This integration can effectively bridge critical gaps within current urban transit systems, contributing positively toward broader sustainability goals[3]. Despite these promising benefits, challenges arise from integrating micro-mobility with traditional urban road and pedestrian infrastructures. The coexistence of different mobility modes, each operating at distinct speeds and patterns, introduces potential collision risks and pedestrian safety concerns[4]. Such issues underscore the strategic necessity of dedicated micro-mobility infrastructure within sustainable urban transportation frameworks. This study explores the policy implications and projected impacts associated with implementing dedicated micro-mobility lane in major urban centers. By specifically examining internal, destination-based, and through traffic flow patterns, the research underscores micro-mobility’s potential role in enhancing short-distance travel efficiency, fostering improved integration with public transportation systems, and redistributing through-traffic to alleviate urban congestion. Consequently, from a sustainable urban transportation planning perspective, the study systematically establishes the practical and policy-driven rationale supporting the expanded adoption of dedicated micro-mobility infrastructure.

ABSTRACT. There are vital strategies that constitute the absolute leverage in the food industry: branded products and differentiation, both attributes of branding strategies. In recent years, the demand of branded cooperative products has boosted, as new needs have emerged in the Greek fresh food market. Specifically, there are few Greek marketing cooperatives that have successfully entered in fresh food market promoting their fresh agricultural products. The consumers consider that agricultural cooperatives play substantive social and economic role in Greek society. This statement is since agricultural cooperatives reinforce incomes of producers, ensuring fair prices for Greek consumers and create reliable marketing channels for independent Greek producers. The bargaining power of producers is able to boost cooperative identity and branding policy, helping Greek agricultural production for more homogenous fresh agricultural products. In addition to, Greek consumers consider that Greek agricultural cooperatives should focus mainly to availability and quality of their fresh products, organizing appropriate activities towards the consumer public. The purpose of this paper is to contribute a better meaning of consumers’ behavior and market experts’ opinions towards fresh agricultural products, in order to investigate how they are familiar to branding strategies. The findings of the study recorded that there are discrepancies between market experts’ opinions based on whether it’s a supermarket or a delicatessen grocery store. Evidence showed that fresh cooperative products are more likely to be found in a delicatessen grocery store due to their quality as well as their branded identity.

Results of two factors that arose by factor analysis, indicated that the Greek consumers want market experts to invest to concepts of “Loyalty” and “Solidarity” because they consider that these concepts are inextricably linked to the cooperative movement and values carried by fresh cooperative products.

ABSTRACT. Microorganisms play a crucial role in wastewater treatment, yet the ecological processes shaping microbial communities and their impact on wastewater treatment plant (WTP) performance remain unclear. Understanding these dynamics, keystone taxa, and their interactions could optimize operations, enhance system stability to disturbances, and reduce environmental impacts. In this work, we examined microbial community succession following effluent application in pilot-scale constructed wetlands (CWs). Our results reveal significant shifts in microbial α and β diversity, particularly during the initial phase. Applying the iCAMP framework to quantify the contribution of microbial community assembly processes reveal a dominance of selective processes early in the operation period, but stochastic processes, especially drift, become more influential over time. Hierarchical clustering of differentially abundant ASVs helped us to identify critical groups of taxa involved in wastewater performance, to delineate ecological niches and improve our understanding on microbial interactions, offering insights into their roles. These findings highlight the potential of microbial clusters as bioindicators for assessing treatment efficiency and system stability, ultimately improving the modeling and performance of WTPs.

ABSTRACT. Starting from the Environmental Footprint method, in this work we present the outcome of a preliminary investigation on the potential benefits arising from the increase in the number of uses when comparing a standard T-shirt and a T-shirt that is produced with more fabric mass as a means of making it more durable. The environmental impacts are quantified via life cycle assessment, in which the functional unit is a 200g cotton T-shirt which is used on average 50 times. The impact method used is the Environmental Footprint 3.1 assessment method including all 16 impact categories. Focusing on climate change, the results show that producing a T-shirt that is worn only once can have very negative impact. Yet, the more times the T-shirt is worn the less its impact per use becomes. In addition, the results show that this reduction in the per use impact is not linear, but it diminishes asymptotically, so the gains from using it 10 more times, because it is more durable, is different when that goes from 20 uses to 30 uses comparing to when that goes from 70 uses to 80 uses.

ABSTRACT. The concept of the circular economy (CE) has gained significant attention globally as a sustainable approach to mitigating environmental degradation, reducing waste, and promoting resource efficiency. However, the application of CE in Africa remains under-explored, with varying challenges and opportunities specific to the region. This scoping review investigates the current state of CE implementation across Africa, drawing on academic literature, policy documents, and case studies to provide an overview of the factors influencing the uptake of circular practices. Key areas explored include waste management systems, industrial symbiosis, resource recovery, and the role of informal sectors in CE adoption. The review also highlights the economic, social, and political challenges faced by African countries, including infrastructure gaps, limited regulatory frameworks, and financial constraints. Despite these challenges, the study identifies promising trends, such as local innovations in resource reuse, growing policy interest, and international collaborations aimed at fostering CE principles. The review calls for a deeper examination of how CE can be tailored to fit Africa’s unique socio-economic context, emphasizing the importance of inclusive growth, capacity building, and partnerships to drive sustainable development. By mapping the current landscape, this review lays the groundwork for future research and policy interventions aimed at advancing CE in Africa, offering valuable insights into the continent’s potential to transition to a more sustainable, circular economy. Key findings suggest that while CE practices are still in nascent stages across much of Africa, there is considerable potential for growth through improved governance, innovative financing, and integration of indigenous knowledge systems. The paper concludes with recommendations for further research and policy development that could enhance CE initiatives and contribute to sustainable development across the continent.

ABSTRACT. The concept of a circular bioeconomy has gained significant attention in the context of sustainability, emphasizing the transformation of renewable biological resources and waste into bio-based, value-added products (Ozbayram, 2021). Aquatic macrophytes, also known as hydrophytes, are essential components of aquatic and wetland ecosystems. They are considered key components of aquatic ecosystems and they also provide multiple benefits for humans. The most important supporting services provided by these plants are related to nutrient cycling and provisioning of habitat, but macrophytes also participate in water cycling and gases production (Lamberts et al, 1998; Cai and Bongers 2007;). The presence of macrophytes and their activity enhance water purification and disease control which are important regulating services. Even they have lots of positive advantages, biological invasions of macrophytes are a worldwide phenomenon. Invasive macrophytes increased habitat complexity, hypoxia, allelopathic chemicals, facilitation of other exotic species, and inferior food quality leading to a decrease in abundance of native fish and macroinvertebrate species. While the rapid spread of both native and non-native freshwater macrophytes can pose ecological challenges, they can be used in wide variety of applications such as biomarkers, phytoremediators, and sources of valuable metabolites such as antimicrobials, herbicides, insecticides, and pharmaceuticals (Su et al., 2018). Additionally, their ability to generate substantial biomass makes them highly useful across various industries. With a protein content ranging from 11% to 32% and lipid content between 3% and 17%, freshwater macrophytes serve as a valuable feed ingredient in aquaculture, offering a well-balanced amino acid profile. Given the increasing global demand for protein, utilizing macrophytes as an alternative to fishmeal holds significant potential for transforming aquaculture. Furthermore, freshwater macrophytes can be integrated into agriculture in multiple ways, offering various benefits. The role of macrophytes in freshwater phytoremediation has been extensively documented by various researchers. This includes both their natural establishment in aquatic environments and the processing of their biomass into absorbent materials, a method known as phytoextraction (Yongabi et al., 2018; Bashir et al., 2020). Numerous freshwater macrophyte species have demonstrated the ability to remove contaminants such as heavy metals, hydrocarbons, and pesticides from water (Xue & Yan, 2011; Li et al., 2019; Guedes-Alonso et al., 2020; Demers et al., 2020). Additionally, the application of fresh tissues from species like Hydrilla verticillata (waterthyme) and Phragmites australis (common reed) has been shown to enhance crop productivity, particularly in maize, by enriching the soil with essential nutrients such as nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), and calcium (Ca) (Mamolos et al., 2011; Jain & Kalamdhad, 2018; Jha, 2021). As the global population continues to grow, it is essential to explore sustainable agricultural alternatives that support food production while minimizing environmental impact. One promising approach involves utilizing freshwater macrophytes as an agricultural resource. These plants contribute to soil fertility, enhance microbial communities, improve soil structure, eliminate pollutants, and accumulate antimicrobial metabolites. These processes promote plant growth, increase crop yields, reduce dependence on chemical fertilizers, and help control plant diseases. While repurposing invasive macrophyte biomass in agriculture presents significant environmental, economic, and agricultural benefits, their availability is limited. Since these plants are not evenly distributed worldwide, their sustainable management is crucial to maximizing their potential as a renewable resource. Furthermore, they can be utilized in biogas plants for energy production. Overall, incorporating freshwater macrophytes into a circular economy framework offers a sustainable solution for resource utilization, transforming their biomass into valuable products for agriculture, water treatment, renewable energy production and valuable-materials.