Recycling Of Products Research Articles

Mass flow and ecological risk of heavy metals in anaerobic digestion of food waste

Conversion of food waste (FW) to bioenergy via anaerobic digestion (AD) has become a topic of worldwide research interest. However, the content, distribution, and speciation of heavy metals (HMs) in feedstock and digestate samples throughout the AD process are currently unknown. Especially, the potential ecological risk (PER) of solid digestate with potential of land application was vague. Mass flow of HMs (Cr, Cu, Mn, Ni, Zn, As, Cd, Hg, and Pb) were estimated in a two-stage wet AD of FW plant in Shenzhen, China. Furthermore, the PER of the HMs in solid digestate (SD) was studied. The findings revealed that the variation in the HM contents of the intermediates, as well as the comparatively high HM contents of the SD, were mostly influenced by the total solid contents of the samples, since HMs tend to adhere to the solid matrix. As per mass balance, the Cr and Ni contents of the digestate samples were 4.7 and 5.5 times higher than in the feedstock samples, respectively. The remaining metals were within the range of 82.2126.1%. Furthermore, the enrichment of HMs in SD must be resolved before reclamation. Moreover, the PER of the HMs in SD was 279.6, considered as a considerable risk level, of which Hg and Cd contributed 46.3% and 33.6%, respectively. This research presents a case study for quantitatively assessing the distribution of typical pollutants throughout the AD process, and it offers preliminary data for potential environmental issues caused by digestion product recycling.

A Business Management Model in the Circular Economy: Technological Solutions for Plastic Recycling

Objectives: this article develops a model for managing business processes in a circular economy using technologies for plastic recycling. Theoretical Framework: The theoretical idea and basis of the article consists in the development of project management methodology, process approach in the closed-loop economy, development of methods and economic tools aimed at effective resource management taking into account waste reduction and increased reuse of plastic fractions in Municipal Solid Waste (MSW). The application of digital technologies and solutions in the context of business process management in the field of plastics recycling will be substantiated, which will allow to identify new opportunities and reserves for optimising business processes in this field, increasing the efficiency of resource use, improving the environment and reducing costs. Method: the work uses a project approach, a process approach, digital modeling methods, and the “polluter pays” method. To implement the process approach, it is proposed to use the concept of Business Process Management (BPM). Competent business process management allows the company to react quickly to changing market conditions and customer orientation. Digital modelling in this paper means the representation of actions in the form of business processes in the organisation of solid waste management, the 'polluter pays' method means the economic assessment and accounting of environmental damage in waste management in the costs of business processes. Results and Discussion: The results of the study can be used to introduce the process approach to plastics recycling in individual regions and countries for the development of a green economy. According to the estimates of the authors, the optimisation and cost reduction of business processes, taking into account the environmental factor and the increase of the revenue part of the project from the reuse and inclusion in the economic turnover of plastic waste recycling products on the scale of the considered city (population of 1800 thousand people, area of 2856 ha, 18.14 tonnes of plastic waste accumulated per day) will reduce the costs of business process management by more than 200 thousand euros. Research Implications: the results of the study can be used to justify projects for the processing and recycling of solid municipal waste, including plastic waste, to introduce environmentally friendly production, to reduce the negative impact on the environment, to develop a process approach to the organisation of all activities for the collection of plastic waste in the city, district. In addition, the application of the proposed approach allows to obtain economic benefits for companies through the sale of secondary resources for the processing of plastic waste, as well as to reduce the negative impact on the environment. Originality/ Value: The originality of the research and its value lies in a new scientific formulation of the problem of reducing environmental pollution from plastic waste through the use of business processes in the field of plastic recycling and digital solutions, as well as the possibility of practical application of the results obtained in the field of green economy.

Sustainability synergies and trade-offs considering circularity and land availability for bioplastics production in Brazil

Alongside the concerns of waste management, plastic production represents a future problem for managing greenhouse gas emissions. Advanced recycling and bio-based production are paramount to face this challenge. The sustainability of bio-based polyethylene (bioPE) depends on the feedstock, avoiding stress on natural resources. This work discusses Brazil’s potential to meet future global bioPE demand by 2050, using sugarcane as feedstock and considering environmental sustainability for production expansion. From the assessed 35.6 Mha, 3.55 Mha would be exempt from trade-offs related to land use change (dLUC), biodiversity, and water availability. The scenario with the highest circularity efficiency would require 22.2 Mha to meet the global demand, which can be accommodated in areas with positive impacts in carbon stocks, neutral impacts in water availability, and medium impacts on biodiversity. Here, we show that dropping demand is essential to avoid trade-offs and help consolidate bioPE as a sustainable alternative for future net-zero strategies.

Modern Methods of Asbestos Waste Management as Innovative Solutions for Recycling and Sustainable Cement Production

Managing asbestos waste presents a significant challenge due to the widespread industrial use of this material, and the serious health and environmental risks it poses. Despite its unique properties, such as resistance to high temperatures and substantial mechanical strength, asbestos is a material with well-documented toxicity and carcinogenicity. Ensuring the safe removal and disposal of asbestos-containing materials (ACM) is crucial for protecting public health, the environment, and for reducing CO2 emissions resulting from inefficient waste disposal methods. Traditional landfill disposal methods have proven inadequate, while modern approaches—including thermal, chemical, biotechnological, and mechanochemical methods—offer potential benefits but also come with limitations. In particular, thermal techniques that allow for asbestos degradation can significantly reduce environmental impact, while also providing the opportunity to repurpose disposal products into materials useful for cement production. Cement, a key component of concrete, can serve as a sustainable alternative, minimizing CO2 emissions and reducing the need for primary raw materials. This work provides insights into research on asbestos waste management, offering a deeper understanding of key initiatives related to asbestos removal. It presents a comprehensive review of best practices, innovative technologies, and safe asbestos management strategies, with particular emphasis on their impact on sustainable development and CO2 emission reduction. Additionally, it discusses public health hazards related to exposure to asbestos fibers, and worker protection during the asbestos disposal process. As highlighted in the review, one promising method is the currently available thermal degradation of asbestos. This method offers real opportunities for repurposing asbestos disposal products for cement production; thereby reducing CO2 emissions, minimizing waste, and supporting sustainable construction.

Key Factors Influencing Consumer Choices in Wood-Based Recycled Products for Circular Construction Sector

This article explores the integration of wood recycling and reuse practices within construction and reconstruction processes, as highlighted in a wood products questionnaire. The aim of this study is to understand how the Romanian consumers perceive the circular economy in order to adopt responsible consumption models. The working instrument consisted of a questionnaire. The questionnaire was applied to 60.7% urban respondents and 39.3% rural ones and consisted of 23 items. The response rate was 68.5% for certain items (257 responses). In the first part, the integration of wood recycling and reuse practices within construction and reconstruction processes is examined. Emerging recycling techniques and demolition processes, particularly incorporating reused, reconditioned, and recycled wood in the construction industry, are evaluated. The economic and environmental implications of these practices are also examined, contributing to the discussion of eco-design policies, and construction waste management and standards. In the second part, insights are provided into how Romanian consumers’ knowledge of CE principles, information about product characteristics, and attitudes influence the demand for recycled wood products. The study concludes with recommendations for better promotion strategies of wood-based recycled products, aiming to increase awareness of its long-term environmental and socio-economic benefits. Additionally, it suggests the need for providing more information on the environmental benefits of wood-based recycled products, and for a more active engagement of stakeholders in the transition to a circular economy. The results serve as a basis for a better understanding of Romanian consumers’ adoption of sustainable consumption behavior in agreement with circular economy concepts and SDGs. While the majority of respondents generally shows openness to an eco-friendly product, mere promotion of these principles may not suffice to change entrenched behaviors and purchasing habits.

Study of Physical Mechanical Characteristics, Economic Viability, and Carbon Emission Impacts of Recycled Aggregate

aims: The study aims to evaluate the viability of using recycled aggregate (RA) from construction and demolition waste (CDW) as a sustainable alternative to natural aggregates in concrete production. background: Construction and demolition waste constitutes a significant portion of solid waste worldwide, posing considerable environmental challenges. objective: To assess the mechanical properties and economic benefits of concrete made by substituting natural aggregate with recycled aggregate, and to understand the environmental impact through a lifecycle assessment of carbon emissions. method: The research involved analyzing the mechanical properties of RA, including density, water absorption, and crushing strength. A critical threshold for material efficiency was determined by substituting natural aggregate with RA in varying proportions. An economic analysis was performed to evaluate the financial viability, and a lifecycle assessment was conducted to quantify carbon emissions from concrete production to site transportation. result: Recycled aggregate concrete showed lower density, higher water absorption, and reduced crushing strength compared to natural aggregates. Optimal strength was achieved with a 40% replacement rate. Economic analysis indicated a favorable return on investment. Lifecycle assessment revealed that raw materials account for approximately 85% of total emissions in recycled concrete production. conclusion: Recycled aggregate is a feasible alternative to natural aggregate in concrete production up to a 40% substitution rate, offering significant mechanical, economic, and environmental benefits. However, optimizing raw material usage is crucial for enhancing the sustainability of recycled concrete. other: The study highlights the growing role of recycled aggregate in engineering applications and underscores the importance of advances in research and application methods to further integrate recycled materials in construction practices.

Assessment of carbon emissions and reduction potential in China's copper smelting industry

AbstractAs the largest producer and consumer of copper, China is facing enormous challenges from carbon peaking and neutrality. This article adopts “bottom‐up” and “top‐down” methods to construct a more accurate model, to predict the CO2 emissions of China's copper smelting industry, and explores its potential for carbon reduction in the future from three scenarios as the baseline scenario (BAU), the general low‐carbon (NLC), and the enhanced low‐carbon (ELC). The results show that the CO2 emissions can achieve a peak in 2028 either in NLC or ELC scenarios, with a peak range of 14.9–16.88 million tonnes. Prior to reaching the peak, the contributions of energy adjustment, material substitution, and process selection to carbon reduction have significantly improved, and the contribution rates increased from 30.91%, 4.11%, and 1.46% to 42.7%, 32.07%, and 15.63% in ELC scenario. After the peak, the contribution of energy adjustment gradually slows down, while the material substitution continues to increase, and the contribution rates increased from 21.25% and 32.07% to 29.38% and 40.01% in NLC and ELC scenarios. In the future, concentrate oxygen‐enriched bottom‐blowing smelting and direct refining from waste copper anode furnaces show ideal potential for carbon reduction before 2025, increasing the proportion of recycled copper production, and adjusting energy structure will be more effective from 2025 to 2035. The conclusions of this study can provide a scientific basis for formulating policy recommendations for green and low‐carbon development of the copper industry in China and all over the world in the future.

Mixed integer programming and multi-objective enhanced differential evolution algorithm for human–robot responsive collaborative disassembly in remanufacturing system

The recycling of waste products is essential for resource reuse. However, turning operation direction causes significant fatigue to operators handling end-of-life (EoL) products, consequently degrading the recycling efficiency. Accordingly, this study employs responsive collaboration robots to aid operators in turning the operation direction of disassembled products. To solve the human-robot responsive collaboration disassembly line balancing problem (HRRC-DLBP), a mixed integer programming (MIP) model is constructed, and a decoding mechanism is designed in this study. Additionally, a multi-objective enhanced differential evolution algorithm (MEDE) in which the decoding mechanism is incorporated is devised and applied to solve the HRRC-DLBP. The MEDE algorithm is validated by comparing its solution results with those of the MIP model. Finally, the MEDE is used to optimise the EoL printer case for the HRRC-DLBP and the disassembly line balancing problem in which the operation direction is turned by humans (H-DLBP). The optimisation results show that the recycling of EoL products is more efficient using the HRRC-DLBP than employing the H-DLBP.

Selecting the most successfull recycling strategy over daily consumption products: application of q-Rung Orthopair Fuzzy Topsis method

Recycling is the process of collecting and reusing that helps the countries to achieve their sustainable development goals. This study, for the first time in the literature, considers the recycling of many daily consumption products as a decision-making problem with the q-rung orthopair fuzzy (q-ROF) approach. In Turkey, recycling initiatives are primarily led by the government and municipalities, involving either reprocessing in public facilities or collaboration with private enterprises. The research evaluates the effectiveness of recycling strategies, considering paper, plastic, textiles, batteries, frying oils, electronics, glass, and wood as alternative products. Criteria such as convertibility rate, resource usage for recycling, converted product lifespan, recycling process complexity, economic gain, product consumption rate, and trading opportunities are employed in the decision-making process. The q-rung orthopair fuzzy Technique for Order Preference by Similarity to Ideal Solution (q-ROFTOPSIS) method is applied to assess these criteria. Decision makers, comprising a recycling expert, a recycling business engineer, and an academician specializing in recycling studies, contribute to the evaluation. The study reveals electronic products as the most successful in recycling, while frying oils exhibit the least success.

From waste to advanced resource: Techno-economic and life cycle assessment behind the integration of polyester recycling and glucose production to valorize fast fashion garments

This work demonstrates the technical, economical, and environmental viability of integrating enzymatic hydrolysis, mechanical refining, and total chlorine-free (TCF) bleaching processes for industrial-scale production of glucose from textile waste. The process features an innovative mechanical refining pretreatment coupled with TCF oxidation of dyes to achieve over 90% improvement in enzymatic hydrolysis yields of cotton textile waste while also promoting the purification and recycling of synthetic fibers. A comprehensive techno-economic analysis was performed based on a 14,000 bone dry tons (BD tons) annual glucose production line, utilizing both 100% cotton and cotton/polyester blends, reveals capital investments ranging from USD 5.6 to 7.9 million, with manufacturing costs per ton of glucose varying between USD 215 and USD 475, depending on the textile blend used. The cotton/polyester 50/50 blend scenario had the lowest minimum selling price (USD 290 per ton of glucose) due to the revenue from the unhydrolyzed synthetic fibers, which are a valuable and key co-product. A sensitivity analysis highlights the significant influence of recycled polyester content and market prices on the economics. Additionally, a life cycle assessment was performed to compare the carbon footprint of the four scenarios. In contrast to other existing pretreatments that can contribute to up to 70% of the emissions in enzymatic hydrolysis of textiles, the mechanical refining pretreatment can contribute as low as 10% of the total emissions in the process proposed in this work. While certain challenges remain, such as the development of a robust supply chain model, the conversion pathway shown in this work for upcycling cotton textile waste into value-added chemicals represents a promising opportunity to combat textile landfilling and foster the circular economy within the industry.

Analysis of NCM concentration and extraction efficiency in the lithium-ion battery extraction process

In recent years, with the increasing popularity of portable electronic devices (PEDs) and electric vehicles (EVs), the demand for lithium-ion batteries (LIBs) has continued to expand; however, the supply of raw materials such as nickel cobalt, and manganese (NCM) is limited, and it is essential to develop efficient recycling technologies. Hydrometallurgical methods, particularly extraction processes, can be used to obtain high-grade recycled LIB products with proper control of the process window. This study focused on the separation of NCM from copper (Cu) and aluminum (Al) by diluting the metal concentrations ([Me]) and adjusting the pH (using NH4OH) during extraction. For metal composition analysis, in addition to using inductively coupled plasma mass spectrometry (ICP-MS), ultraviolet–visible (UV–Vis) spectroscopy and colorimetric analysis were also employed to monitor ion concentrations. The change in solution color is directly related to the nickel (Ni) and cobalt (Co) ion concentrations. Moreover, a continuous shift in the Ni ion absorption spectra at different pH values did not occur for the Co ion absorption spectra. According to the extraction efficiency (EE%) results, the lower [Me] resulted in the higher EE% of NCM. The optimal process window was established within the range of 0.025–0.1 M and pH = 6.5–7.4.

Life cycle assessment of concrete incorporating all concrete recycling products

This study evaluates the environmental impact of concrete incorporating locally available raw materials through life cycle assessment (LCA). It explores the integration of all concrete recycling products in the concrete mixes, including recycled concrete aggregates (coarse and fine) as alternative aggregates and ternary blended cements made with recycled concrete powder and waste perlite powder. With the declining availability of conventional supplementary cementitious materials like fly ash and blast furnace slag, alternative resources are essential. The developed concrete mixes reduced the climate change impact by up to 12% when ternary blended cements were used instead of ordinary Portland cement with the same aggregate mix. This can be attributed to the utilisation of industrial waste in the binder, which are locally available without any environmental burden other than transportation. The study maintains the same workability class and assesses the competitiveness of the developed mixes across strength classes, with notable environmental benefits recognised for the C50/60 strength class. A comprehensive assessment of the life cycle inventory (LCI) of the raw materials revealed significant variability between different sources for recycled aggregates, demonstrating the necessity for adopting a range of LCI data for alternative raw materials in the absence of specific data. Transparent reporting of production and transportation data is essential to improving LCA accuracy. The study shows the feasibility of developing circular concrete mixes that incorporate all products from the concrete recycling process, highlighting that optimising material performance and reducing reliance on conventional materials are crucial for increasing their attractiveness to the construction industry.

Assessing the impact of environmental component on the development of Russian banks applying ESG policy

Subject. The article discusses operations of steadily developing Russian banks in the context of environmental component. Objectives. The aim is to identify patterns in functioning of Russian banks, applying ESG policy in their activities, under the influence of environmental factors, to improve the management of their development. Methods. The study employs regression analysis. We selected 26 Russian banks based on ESG ratings, formed an empirical base for 2011–2020 from open sources (financial and economic indicators and macro-level indicators characterizing the environmental impact by the activities of economic entities), built a linear regression model in MS Excel. Results. The constructed regression model helped reveal that the indicator “Recycling and disposal of production and consumption waste in the Russian Federation” has a significant positive impact on the pretax profit of banks applying ESG policy. However, a negative trend in the impact of banks on the environment was identified in terms of connection between the resulting indicator and the indicator “Primary energy intensity level”. This suggests that the internal capacity of banks to implement the environmental component is not sufficiently developed and used. Conclusions. The findings can be used both at the macro and micro level when generating the strategy and tactics for ESG banking development. The offered regression modeling technique can be used to analyze the role of environmental component in the activities of banks in other countries, which implement ESG policy.

Integrated Benefits of Sustainable Utilization of Construction and Demolition Waste in a Pressure-State-Response Framework

This study presents the first application of the pressure-state-response (PSR) model in the comprehensive assessment of construction and demolition waste (CDW) recycling benefits. Unlike traditional methods, the PSR model provides a multi-dimensional analysis that integrates economic, environmental, and social factors, offering a more holistic approach to evaluating the impact of CDW recycling strategies. This model enables stakeholders to better understand the pressures, states, and responses involved in CDW management, providing actionable insights to optimize recycling efforts and support sustainable urban development. Using the pressure-state-response (PSR) logical framework of sustainable economics, this paper systematically analyzed the comprehensive benefit mechanism of the recycling of construction and demolition waste (CDW), and designed a comprehensive benefit evaluation model for CDW recycling. At the same time, taking Chongqing as an example, the management status of construction and demolition waste, the supply and demand matching of sustainable recycling products, and the impact of the input and output of CDW management were analyzed. The results were as follows: (1) The recovery rate of urban manure fluctuated between 0.13 and 0.17, mainly in temporary landfill. (2) Based on the latest market demand data of CDW recycled products, the supply–demand ratio of recycled products fluctuated between 0.11 and 0.21. This change in the supply–demand ratio reflects improvements in recycling technologies, such as the introduction of C2CA technology, which has greatly increased the supply of high-quality recycled materials. In addition, government policies encouraging the use of recycled products in public projects have contributed to this shift, further aligning supply with market demand. (3) The benefit–cost ratio of CDW management reflects new recycling technologies and the improved efficiency of CDW management. The benefit–cost ratio, which currently fluctuates between 0.32 and 0.39, more accurately reflects the current state of CDW management, which is increasingly adopting advanced technologies, resulting in increased efficiency and reduced costs. Based on this, this paper discusses the supply–demand relationship and benefit–cost ratio in CDW management from supply-side and demand-side perspectives, and puts forward corresponding countermeasures and suggestions. The research results provide a clear reference for improving the efficiency of building demolition waste resource utilization, especially in optimizing the balance of market supply and demand, and improving the economic benefits of recycled products. By analyzing the balance between the supply and demand ratio and the benefit–cost ratio, this study helps inform policy makers, businesses, and investors, to promote the sustainable development of CDW recycling projects to maximize resource efficiency, while reducing environmental pressures. These results not only provide practical guidelines for the implementation of CDW recycling projects, but also lay a foundation for future policy formulation and the setting of industry standards.

Promising areas of slag processing in ferrous metallurgy

The characteristics of promising areas of slag processing in ferrous metallurgy are given. An increase in requirements for environmental protection was noted. Modern slag processing includes primary and secondary processing, which differ in the physical state of the slag. The technological foundations of mass processing of slag have been formed at the Ural Institute of Metals. An assessment of the state of slag processing shows that the capacity of crushing and screening plants, mainly due to complexes purchased abroad, exceeds the yield of slag of current production and leads to a decrease in dumps. Modern areas of economics and environmental protection require the creation and implementation of new technologies and equipment for the processing of slag in liquid and solid form, improving the quality of products at all stages of processing. Processing of slag in liquid form at furnace (or located near melting furnaces) plants will make it possible to organize the technological process in highly economical environmentally friendly small-sized units, to adjust the composition and properties of slag, to expand the range and quality of the resulting products, to create conditions for the utilization of melt heat and the recycling of slag processing products. These processes reduce the environmental burden on the environment, reduce material, energy and operational costs, and expand the range and quality of the products obtained

Identification and characterization of a novel polyamide hydrolase

The widespread use of non-naturally degradable plastics is causing increasingly serious harm to the environment. Reducing plastic pollutants has become the core of ecological and environment management. Biological methods such as enzymes demonstrate advantages in depolymerizing plastics with mild reaction conditions and recycling of depolymerization products. However, there are few reports on the biological depolymerization of polyamide plastics. In this study, by using 4-nitropropionanilide as the model substrate, we screened against our plastic depolymerase library and obtained a Meiothermus ruber-derived enzyme (MrABH) that can hydrolyze the polyamide bond. We expressed this enzyme in Escherichia coli and purified the protein by affinity chromatography. Furthermore, we investigated the catalytic properties, enzymatic properties, and catalytic products of this enzyme with polyamide as the substrate. MrABH had good stability at pH 8.0-10.0, with the optimal performance at pH 9.0 and 30 ℃. The catalytic performance of this enzyme for ester bonds and amide bonds was similar. MrABH can catalyze the depolymerization of PA6 and PA66 to produce monomers and oligomers, demonstrating the potential to be used in the depolymerization and recycling of polyamide.

Flower pollination algorithm with ring topology for multi-solution spaces to solve the disassembly line balancing problem

Abstract The Disassembly Line Balancing Problem (DLBP) is of significant importance in the product recycling process. However, existing DLBP research have primarily proposed improved optimization algorithms for single solution space. To provide decision makers with more efficient disassembly solutions, this paper chooses three classical layouts (straight, U-shaped, and parallel) to broaden the solution space and expands an incomplete DLBP with multi-solution spaces (DLBP-MS). By employing the strategy of incomplete disassembly, only the essential components are retained. In DLBP-MS, the disassembly information from used products is processed and imported into the three types of disassembly spaces to be solved and compared to find suitable disassembly solutions. And a multi-objective mathematical model is developed, this includes factors such as workstation count, free time, disassembly smoothness index, carbon emission, and disassembly revenue. The part constraints are established based on directed graphs, and the encoding and decoding methods for multi-solution spaces disassembly sequences in the random incomplete case are designed respectively. A ring topology based flower pollination algorithm (RTFPA) is introduced to effectively address the DLBP-MS. The solution set obtained during the iterative process is divided into subsets based on the congestion level and the overall diversity is preserved by internal optimization of these subsets. After that, the RTFPA is applied to the DLBP-MS of waste cell phones and computers. The improvement of the algorithm's optimization ability under different solution spaces is verified by comparing the results with those obtained from four other algorithms.

Selective Recycling of Spent Lithium‐Ion Batteries Enables Toward Aqueous Zn‐Ion Batteries Cathode

AbstractEffective selective recycling of spent lithium‐ion batteries (S‐LIBs) and giving recycled products a “second life” are crucial for advancing energy supply circularity, environmental and economic sustainability development. However, separating metal compounds with similar charge differences requires substantial energy, water, and chemical inputs. Herein, an innovative strategy is present for selective recycling S‐LIBs by photoexcitation inspired by the Hard Soft Acid Base (HSAB) principle. Theoretical calculations and experimental results show that photoexcitation drives charge transfer and modulates subtle charge density differences among metal components, thereby enhancing their solubility disparity and facilitating metal separation. Remarkably, the photoexcitation‐induced metal separation factor reaches 46900 and the metal recovery efficiency approaches 100%, representing a significant improvement over non‐photoexcitation separation with a separation factor of non‐photoexcitation of merely 2.7. Through techno‐economic analysis, the viability of photoexcitation selective recycling technology has been confirmed as an eco‐friendly and economical approach for battery recycling. Furthermore, high‐value reuse of recovered Mn components is implemented. The Recycled Mn components are treated by calcination to obtain porous, defect‐rich Mn2O3, which showed a specific capacity of 613 mAh g−1 at 0.1 A g−1) in aqueous Zn‐ion batteries (AZIBs). This work provides fresh insight into recycling S‐LIBs and moving toward more sustainable storage technologies.

Unified Modeling and Multi-Objective Optimization for Disassembly Line Balancing with Distinct Station Configurations

Disassembly line balancing (DLB) is a crucial optimization item in the recycling and remanufacturing of waste products. Considering the variations in the number of operators assigned to each station, this study investigates DLBs with six distinct station configurations: single-manned, multi-manned, single-robotic, multi-robotic, single-manned–robotic, and multi-manned–robotic setups. First, a unified mixed-integer programming (MIP) model is established for Type-I DLBs with each configuration to minimize four objectives: the number of stations, the number of operators, the total disassembly time, and the idle balancing index. To obtain more solutions, a novel bi-metric is proposed to replace the quadratic idle balancing index and is used in lexicographic optimization. Subsequently, based on the unified Type-I models, a unified MIP model for Type-II DLBs is established to minimize the cycle time, the number of operators, the total disassembly time, and the idle balancing index. Finally, the correctness of the established unified models and the effectiveness of the proposed bi-metric are verified by solving two disassembly cases of lighters and hairdryers, which further shows that the mathematical integration method of unified modeling has significant theoretical value for the multi-objective optimization of the DLBs with six distinct station configurations.

Eco‐friendly synthesis of non‐isocyanate polyurea using PET and CO2 upcycling: A double green approach

AbstractFrom the perspective of sustainability, this research explored both the recycling of polyethylene terephthalate (PET) and the conversion of carbon dioxide (CO2) into polymer materials. To this end, a series of copolyurea specimens were synthesized through the polycondensation of carbon dioxide with hexamethylenediamine (HDA) and terephthalic dihydrazide (TDH), where TDH was derived from the chemical recycling of PET via the aminolysis method. FTIR spectroscopy, 1H NMR, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA) characterized the products of PET recycling and synthesized copolyureas. Additionally, we sought to identify the optimal parameters for both the recycling and copolymerization processes. The results of identification analyses for both the recycling and copolymerization reactions confirmed the formation of the desired structures. An increase in the hard segment (TDH) led to discrepancies between the intended and actual monomer ratios in the synthesis, possibly due to dimethyl sulfoxide (DMSO) solubility issues or unreacted TDH. Furthermore, the TGA analysis indicated that the initial degradation temperature (Td,5%) of the copolymer increased with the proportion of aromatic rings in the hard segment, underscoring the complex interactions within the copolymer matrix affecting its thermal and structural properties. The DSC results revealed that for copolyureas with the formula HDAxTDH100–x (where x = 50, 60, 70, 80, 90), reducing the x fraction or increasing the TDH content lowered the melting temperature. Furthermore, at a high percentage of TDH, the melting point disappeared entirely due to the destruction of the crystalline structure, indicating a critical threshold where the copolymer transitions from a semi‐crystalline to an amorphous state.