Sustainable approaches in concrete production: An in-depth review of waste foundry sand utilization and environmental considerations.

This review critically evaluates the potential of Waste Foundry Sand (WFS) as a substitute for fine aggregate in concrete, conducting a comparative analysis of its physical and chemical properties against those of natural sand. The study synthesizes findings from various research experiments to determine concrete's most effective WFS replacement percentage. It compiles and analyzes data on how different WFS ratios affect concrete's mechanical properties, including modulus of elasticity and compressive strength. The review also consolidates research on the impact of WFS on concrete's workability, density, and flowability. A key finding is that WFS, categorized as a non-hazardous waste, possesses a diverse particle size distribution, rendering it suitable for recycling in various industrial applications.The study identifies that a 20%-30% replacement of WFS in concrete significantly improves properties such as voids, specific gravity, and density. However, it is essential to note that exceeding a 30% WFS replacement can result in increased carbonation depth and decreased resistance, primarily due to sulfur trioxide (SO3). Further observations indicate that incorporating higher levels of WFS in self-compacting concrete reduces its flowability and increases water permeability. Moreover, the review highlights the regulatory and classification challenges associated with using WFS, particularly its classification as waste, which hampers its widespread adoption in construction. In conclusion, the study recommends implementing End-of-Waste (EoW) regulations to facilitate sustainable recycling and environmental protection. Additionally, it includes a bibliometric analysis of foundry sand research spanning from 1971 to 2020, providing a comprehensive summary of the field's historical and recent developments.

Reduction of the environmental and health consequences of cigarette butt recycling by removal of toxic and carcinogenic compounds from its leachate.

Cigarette butt is a hazardous waste, and its management faces many challenges. The generation of leachate containing many pollutants including heavy metals is one of the limitations of recycling cigarette butts. The aim of this study was to reduce organic compounds and heavy metals in leachate resulting from cigarette butt recycling in an electrocoagulation reactor. For this purpose, two samples, including freshly smoked cigarette butts and littered cigarette butts, were processed and the treatment of leachate resulting from them was studied in an electrocoagulation reactor. The efficiency of leachate treatment was investigated in the treatment time of 10-40 min and current intensity of 20-100 mA. The results showed that the minimum reduction of chemical oxygen demand and turbidity was 25.3% and 33.4%, respectively. Increasing the current intensity and treatment time increased the efficiency of removing turbidity and chemical oxygen demand up to 47.1% and 41.2%, respectively, in optimum conditions. The reduction of nickel, chromium, cadmium, and lead in the lowest current density and minimum treatment time was more than 90%, which increased to more than 99% with the increase of the current density and treatment time. The use of electrocoagulation is a suitable solution to reduce heavy metals in leachate resulting from cigarette butt recycling, while the proper reduction of organic compounds in this type of leachate requires further treatment processes.

Exploring the untapped practices in bacterial-fungal mixed-based cultures for acidic treatment of metal-enriched printed circuit board waste.

This study explores the extraction of metals from spent mobile phone printed circuit boards (SMPhPCBs) to address environmental and resource depletion concerns. The challenges in metal recovery from SMPhPCBs arise due to their complex composition and high metal content. While previous research has primarily focused on using bio-cyanide, bio-sulfate, and bio-ferric compounds from acidophilic bacteria, the potential of bio-oxalic acid for SMPhPCBs treatment and the alteration of their complex structure has not yet been explored. Additionally, this study suggests evaluating the untapped potential of Aspergillus niger in oxalic acid production through mixed cultures with bacteria, marking a pioneering approach. A unique culture of Bacillus megaterium and A. niger was created, inducing bio-stress by bacterial metabolites, including gluconic acid (2683 mg/l) and live/dead bacterial cells in a medium with glucose deficiency. Results demonstrated reducing sugar consumption and oxalic acid over-production in mixed cultures compared to pure cultures, ranging from 1350 to 4951 mg/l at an initial glucose concentration (IGC) of 10 g/l and 4276 to 7460 mg/l at IGC 20 g/l. This over-production is attributed to proposed fungal signaling mechanisms to bacteria. Metal extraction using organic acids and siderophores at 10 g/l pulp density, 24 h, and 60 °C yielded Mn (100 %), Pt (100 %), Pd (70.7 %), Fe (50.8 %), Co (48.3 %), Al (21.8 %), among others. The final valuable residue containing copper, gold, and silver holds potential for future recycling. The study concludes with XRD and FTIR analyses to assess the bioleaching effect on the bio-leached powder.

A hybrid thermal-biological recycling route for efficient extraction of metals and metalloids from end-of-life liquid crystal displays (LCDs).

Waste liquid crystal displays (LCDs) are one of the most substantial and rapidly growing e-waste streams that contain a notable amount of critical, precious, and toxic elements. This study presented a novel thermal-biological hybrid method for resource recovery from waste LCDs. Through the design of a multistage thermal treatment process with the addition of optimized 20 wt% B2O3 to waste, the LCD's glass structure was separated into two interconnected phases, resulting in the transfer of metals from the LCD's glass phase to the B2O3 phase that can solubilize in the acid solution. Following the thermal treatment step, the biometabolites of Aspergillus niger were used for bioleaching of In, Sr, Al, and As from the obtained thermally treated product. The optimal bioleaching parameters were a pulp density of 10 g/L, temperature of 70 °C, and leaching time of 2 days, which led to the highest extraction of 82.6% Al, 70.8% As, 64.5% In, and 36.2% Sr from thermally treated LCD waste, representing a multifold increase in Al, As, and Sr extraction levels compared to untreated waste. This study demonstrated that the proposed hybrid method could successfully overcome waste complexities and ensure effective element extraction from discarded LCDs.

A sustainable approach toward mechanical recycling unsortable post-consumer WEEE: Reactive and non-reactive compatibilization.

While near-infrared (NIR) spectroscopy in post-consumer waste electrical and electronic equipment (WEEE) recycling accurately separates white or clear polymers, 40% containing dark plastics, termed 'unsortable WEEE,' are excluded from sorting lines and therefore incinerated or landfilled, causing environmental concerns. This study investigates the potential of using non-reactive and reactive copolymers as compatibilizers to enhance the performance of unsortable WEEE plastics free of brominated flame retardants. To the best of our knowledge, this is the first time that such copolymers have been explored as a solution for improving the compatibility of unsortable WEEE polymer blends. Initial trials with 4% of styrene-ethylene-butylene-styrene copolymer (SEBS-13) and SEBS-30-g-(maleic anhydride) copolymer (SEBS-30-g-MA MA) as compatibilizers showed insufficient results compared to virgin commercial polymers. However, the addition of higher concentrations of compatibilizers (i.e. up to 20 wt%) and the use of a SEBS having a higher styrene content (i.e. SEBS-30) improved the mechanical properties of the material, causing it to transition from brittle to ductile. This behavior was found more pronounced for the 20% non-reactive SEBS-30, for which the SEM analysis showed reduced phase segregation and revealed a more homogeneous fracture surface. This was further supported by Differential Scanning Calorimetry (DSC) analysis, which showed evidence of an interaction between one or more polymer phases. With a room temperature performance equivalent to that of virgin conventional polymers, the SEBS-30 compatibilization approach has made it possible to consider using unsortable WEEE streams as recycled materials in commercial applications.

The global distribution of epidemiological studies involving waste pickers: A systematic review.

Waste pickers, who work with the collection of recyclable materials in search of a source of income, are subject to various risks and diseases that are very well researched. The aim of this systematic review was therefore to identify and analyze the results of epidemiological research on waste pickers over the last 20 years as well as to investigate the geographical distribution and quality of these studies. The studies were selected from the literature by creating search keys with representative keywords in different databases. This systematic review exceptionally includes research qualified according to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines. In total, 61 epidemiological studies with waste pickers were found in 15 different countries, with the largest number of studies carried out in the American continent compared to the African and Asian, respectively. Regarding the quality, 91.80 % were classified as excellent and 8.20 % as good. Although the results show a significant number of epidemiological studies with waste pickers, demonstrating scientific evidence, that there is still a lack of research focusing on waste pickers in different work scenarios, from different health perspectives and in different parts of the world, and it is not possible to highlight the trends in health research for this profession.

A comparative life cycle assessment of recycling waste concrete powder into CO2-Capture products.

Waste concrete powder (WCP), a byproduct of construction and demolition (C&D), currently has a low degree of recycling despite its potential for environmentally friendly applications. WCP can serve as a valuable substitute for cement, offering advantages for resource conservation and carbon sequestration. However, there are very few studies that quantitatively assess the environmental impact of incorporating WCP into the circular economy as a secondary material instead of disposing of it. The energy-intensive processing of WCP raises questions about the optimal carbonation time using available equipment. This study aims to fill this knowledge gap by employing carbon footprint and life cycle assessments (LCA) to optimize WCP recycling. Three recycling WCP scenarios are analyzed. The first scenario involved the conversion of WCP into compacts that absorb CO2 during the carbonation process. The results of the first scenario revealed that the optimal carbonation time for WCP compacts was 8 h, during which 42.7 kg CO2-e per tonne of WCP compacts was sequestered. The total global warming potential (GWP) was -4.22 kgCO2-e, indicating a carbon-negative recycling process. In the second and third scenarios, LCA was conducted to compare the use of carbonated and uncarbonated WCP as a partial replacement for cement in concrete. In these scenarios, it was found that uncarbonated WCP is a more effective solution for reducing the carbon footprint of traditional concrete mixes, achieving a significant 16% reduction of GWP when 20% of cement is replaced. Conversely, using carbonated WCP as a partial cement replacement in concrete mixtures shows limited potential for CO2 uptake. The sensitivity analysis reveals that the carbon footprint of the WCP compacts production process is strongly influenced by the electricity supplier used.

Circular economy strategies for mitigating metals shortages in electric vehicle batteries under China's carbon-neutral target.

Concerns over supply risks of critical metals used in electric vehicle (EV) batteries are frequently underscored as impediments to the widespread development of EVs. With the progress to achieve carbon neutrality by 2060 for China, projecting the critical metals demand for EV batteries and formulating strategies, especially circular economy strategies, to mitigate the risks of demand-supply imbalance in response to potential obstacles are necessary. However, the development scale of EVs in the transport sector to achieve China's carbon neutrality is unclear, and it remains uncertain to what extent circular economy strategies might contribute to the reduction of primary raw materials extraction. Consequently, we explore the future quantity of EVs in China required to achieve carbon neutrality and quantify the primary supply security levels of critical metals with the effort of battery cascade utilization, technology substitutions, recycling efficiency improvement, and novel business models, by integrating dynamic material flow analysis and national energy technology model. This study reveals that although 18%-30% of lithium and 20%-41% of cobalt, nickel, and manganese can be supplied to EVs through the reuse and recycling of end-of-life batteries, sustainable circular economy strategies alone are insufficient to obviate critical metals shortages for China's EV development. However, the supplementary capacity offered by second-life EV batteries, which refers to the use of batteries after they have reached the end of their first intended life, may prove adequate for China's prospective novel energy storage applications. The cumulative primary demand for lithium, cobalt, and nickel from 2021 to 2060 would reach 5-7 times, 23-114 times, and 4-19 times the corresponding mineral reserves in China. Substantial reduction of metals supply risks apart from lithium can be achieved by the cobalt-free battery technology developments combined with efficient recycling systems, where secondary supply can satisfy the demand as early as 2054.

Recycling facemasks into civil construction material to manage waste generated during COVID-19.

Growing plastic pollution in the context of COVID-19 has caused significant challenges, exacerbating this already out-of-control issue. The pandemic has considerably boosted the demand for personal protective equipment (PPE), such as facemasks and gloves, all over the globe, and mismanaging this growing plastic pollution has harmed the environment and wildlife significantly. To mitigate negative environmental impacts, it is necessary to develop and implement effective waste management strategies. This present study estimated the daily facemask generation throughout the pandemic in Iran based on the distribution of urban and rural populations and, likewise, the daily generation of hand gloves in the COVID-19 era and the amount of medical waste generated by COVID-19 patients were calculated. In the next step, the quantities of discarded facemasks dumped into the Caspian Sea, the Persian Gulf, and the Gulf of Oman from the coastal cities were determined. Finally, the innovative alternatives for repurposing discarded facemasks in civil construction materials such as concrete, pavement, and partition wall panel were discussed.

Recycling of waste calcium carbonate in lignocellulosic biorefining chain for chiral lactic acid production.

One of the major end-products of lignocellulosic biorefining chain is the solid residues containing various compounds. The present approach to solid residues treatment is combustion for generation of heat and electricity. This study investigated the potential for recycling of the combustion ash from the solid residues after lignocellulosic dry biorefining process. A range of characterizations showed that the combustion ash contained a high amount of calcium carbonate. By recycling the ash as the neutralizer in biorefining process, the waste calcium carbonate in the ash was efficiently utilized for pretreated biomass neutralization and can replace 40 % of calcium hydroxide for lactic acid production. The chiral L-lactic acid titer reached 102.4 ± 3.6 g/L from 20 % (w/w) solids loading of wheat straw. Three feasible strategies of ash recycling for the investigated biorefinery concept were further proposed base on the rigorous calcium mass calculation, which can efficiently reduce the consumption of neutralizers.

Solid waste management in the context of the waste hierarchy and circular economy frameworks: An international critical review.

Growing populations and consumption drive the challenges of solid waste management (SWM); globalization of transport, food production, and trade, including waste trading, distributes risks worldwide. Using waste hierarchy (WH; reduce, reuse, and recycle) and circular economy (CE) concepts, we updated a conceptual waste framework used by international organizations to evaluate SWM practices. We identified the key steps and the important factors, as well as stakeholders, which are essential features for effective SWM. Within this updated conceptual framework, we qualitatively evaluated global SWM strategies and practices, identifying opportunities, barriers, and best practices. We find that, although a few exceptional countries exhibit zero-waste compliance, most fare poorly, as exhibited by the high waste generation, incineration, and disposal (open dumping, landfilling) volumes. In the Global North, SWM strategies and practices rely heavily on technologies, economic tools, regulatory frameworks, education, and social engagement to raise stakeholder awareness and enhance inclusion and participation; in the Global South, however, many governments take sole legal responsibility for SWM, seeking to eliminate waste as a public "nuisance." Separation and recycling in the Global South are implemented mainly by "informal" economies in which subsistence needs drive recyclable material retrieval. Imported, regionally inappropriate tools, economic constraints, weak policies and governance, waste trading, noninclusive stakeholder participation, data limitations, and limited public awareness continue to pose major waste and environmental management challenges across nations. In the context of the framework, we conclude that best practices from around the world can be used to guide decision-making, globally. Despite variations in drivers and needs across regions, nations in both the Global North and South need to improve WH and CE compliance, and enhance stakeholder partnership, awareness, and participation throughout the SWM process. Partnerships between the Global North and South could better manage traded wastes, reduce adverse impacts, and enhance global environmental sustainability and equity, supporting UN Sustainable Development Goals. Integr Environ Assess Manag 2024;20:9-35. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

A novel process for the complete recycling of exhausted coffee capsules with a fully circular approach: Design of the industrial plant and Techno-Economic analysis of the process.

The objective of this paper is to present the technical and feasibility analysis of an innovative mechanical recycling system for exhausted coffee capsules. This recycling process involved the sorting of spent coffee grounds (SGC) and the subsequent drying and melt-mixing of a portion of these grounds with the remaining capsule components, mainly composed of polypropylene (PP), along with optional virgin PP. These newly developed composite materials exhibited mechanical and rheological properties comparable or even surpassing those of virgin PP. They were also successfully utilized for the injection of new capsule shells, thus alignin with the principles of the circular economy. In addition to the technical aspects, this paper present a comprehensive Techno-Economic Analysis (TEA) of the proposed recycling processes, considering the inclusion of virgin PP (0-20 %) and the initial moisture content (MSGC) of SGC(5-55 %) as varying factors. An industrial plant, designed to handle up to 190 million exhausted coffee capsules and produce up to 1500 tons of recycled compund was appropriately sized. The analysis revealed that processes are profitable across all examined scenarios and that the Net Present Value ranged between 800 k€ (for vPP = 20 % and MSGC = 55 %) and 2000 k€ (for vPP = 0 % and MSGC = 5 %).

Polychlorinated biphenyls in bovine milk from a typical informal electronic waste recycling and related source regions in southern India before and after the COVID-19 pandemic outbreak.

For more than a decade, Chennai city in southern India has been evidenced with informal electronic waste (e-waste) recycling and open burning practices as the potential sources for polychlorinated biphenyls (PCBs). PCBs can bioaccumulate in livestock particularly cows grazing on the contaminated soil. The outbreak of the COVID-19 pandemic led to additional challenges associated with waste management practices. Hence this study aims to elucidate twenty-five PCB congeners in bovine milk from the previously reported PCB source regions in Chennai and the suburbs before and after about three years of the pandemic outbreak along electronic waste recycling (EWR), open burning dumps (OBD), and residential (RES) transects. The geomean concentration of Æ©25PCBs in ng/g lipid weight (lw) followed a decreasing trend of EWR (13 ng/g lw) > OBD (8 ng/g lw) > RES (4 ng/g lw). Over 80 % of PCBs stemmed from EWR and OBD transects before and after the pandemic. However, a significant surge in the level of PCB-52 was observed in the OBD transect after the pandemic outbreak. Most toxic PCB congeners, PCB-126 and -169 were significant contributors to TEQs in EWR and OBD transects and can be reasoned with the burning of waste materials and mixed plastics in these transects. The highest average daily dose (ADD) exposure risk was for children from EWR and was significantly higher (p < 0.05) than other transects. Mean ADD-induced TEQ (6.6 pg TEQ/kg-bw/day) from the cows grazing around Kodungaiyur dumpsite slightly exceeded the EU guideline of 5.5 pg TEQ/kg-bw/day after the outbreak of the pandemic due to PCB-126. However, none of the samples exceeded the US FDA (1.5µg/g milk fat) recommendation limits for PCBs in milk fat. Prolonged exposure to such persistent organic pollutants interlinked with the burning of mixed waste in the open dumps can be a public health concern.

Preferential and efficient extraction of lithium under the combined action of reduction of herb-medicine residue and leaching of oxalic acid.

With the increasing demand for lithium resources, the efficient recovery of lithium from spent lithium-ion batteries (LIBs) has become the focus of social attention. Herein, a combined process of reduction roasting of herb-medicine residue (HMR) and oxalic acid (OA) leaching is proposed to improve the recovery efficiency of lithium. Due to the large amount of reducing gas produced by the pyrolysis of herb-medicine residue, the layered structure of LiNixCoyMnzO2 cathode powder can be destroyed at 650℃ for 10 min, and the cathode powder is converted into Li2CO3, Ni, Co, MnO. Moreover, about 99.6 % of Li in the roasting residue can be selectively extracted by 0.5 mol L-1 oxalic acid for 20 min. Under the combined action of HMR and OA, the extraction efficiency and kinetics of lithium are improved simultaneously. This work achieves synergistic treatment of two types of waste from the perspective of waste management for waste. Meanwhile, it provides an alternative and innovative approach for the difficult problem of low efficiency of lithium recovery from spent LIBs.

Analyzing the territorial dimensions of work through a comparative study of waste recovery facilities in France and Brazil.

BACKGROUND: Waste production and management from residents and collection for sorting are systems heavily dependent on territorial dimensions. Ergonomic research needs to better integrate such territorial determinants to improve work conditions and design sustainable work systems. OBJECTIVE: Through studies in France and Brazil, this paper analyzes the territorial relations that raise work systems' sustainability challenges for materials recovery facilities (MRFs) and waste management in both countries and examines the links between work activity and territory in MRFs. METHODS: Both studies were based on the principles of activity-oriented ergonomics and used analyses of work activity and sociotechnical systems. The French study focused on interventions conducted over a 42-month period in five MRFs. The Brazilian study was based on a 20-month longitudinal qualitative and quantitative study. RESULTS: In this paper, we argue that territory is a key determining factor in waste production and work. Notably, the consumption patterns of residents and the economic flows within a geographic space determine the waste composition; and the territorially specified public policies, which define technical and social dimensions of waste collection and sorting. However, the territorial dimensions of waste are poorly considered in facility design. Workers' health and sorting system performance are thus affected and negatively compromising plant performance. CONCLUSION: The territory appears as a blind spot in the design of work systems. One of the challenges is to create interfaces and devices that could help to integrate better human activity and waste territorialized anchorage, in a multilevel organization, from local communities to the global recycling chains.

New progress in the deep understanding of the biocake layer property: Combined effect of neglected protein secondary structure, morphology, and mechanism.

The application of magnetic fields (MFs) and magnetic particles (MPs) in water treatment has attracted widespread attention due to their stability, strong biological compatibility, and less chemical consumption. This study introduced MPs and MFs to GDM and probed their effects on filtration performance. Predeposited large MPs (P-large) and batch-added little MPs (B-little) intervened biocake layer development, forming more open and porous structures, they also reduced biomass secretion, resulting in flux increases of 13 % in P-large and 40 % in B-little than P-little, respectively. Besides, MFs controlled MPs distribution on the biocake layer, resulting in forming of more rough and open structures. A relatively lower magnetic field of 20 mT facilitated biomass secretion, while a higher magnetic field of 50 mT decreased biomass. Furthermore, applying magnetic fields decreased the ratios of α-helix and ß-sheet, and increased random coil percentage. Thus, applying magnetic field mediation would contribute to the flux improvements in I-20 and I-50 by 29 % and 32 % relative to I-0. Economic analysis suggested introducing MPs and MFs to GDM was economically feasible, synergy of MPs and MFs had more economic advantages on the community scale and MPs-assisted GDM had significant economic advantages on both community and household scales. Future works should focus on developing new technologies for the recycling of MPs and membranes. This study provided new insight into the protein secondary structures associated with GDM performance and would encourage new sustainable MFs and MPs-assisted GDM technological developments.

Stop treating waste pickers like garbage: An autoethnography on informal waste picking in Brazil.

There are almost 8 billion people on the planet with every single one of them producing some type of waste. The cost of recycling and money made by selling recyclable products has created a strong foundation for informal waste picking to exist. Waste pickers sort through garbage to find recyclable material; it is estimated that there are around 20 million waste pickers worldwide. In 2022, I went to experience life as a waste picker in Brasilia, Brazil for a day to understand issues that may continue to exist in this informal industry. I worked in a triage center and used this experience to inform my autoethnography; even though I have worked in waste picker research for almost a decade, this experience led to a different conclusion. The most interesting issue that I found while working as a waste picker was the lack of uniformity in waste picking, which led to people working on the streets or in co-op triage centers. This population is vulnerable which is worsened from exposure to hazards by nature of the informal environment; this situation contributes to ongoing poor working conditions through lack of governmental oversight, policy development, and change. Ultimately, informality needs to be addressed.

Recovery of carbon from spent carbon cathode by alkaline and acid leaching and thermal treatment and exploration of its application in lithium-ion batteries.

The spent carbon cathode (SCC) is a hazardous solid waste from aluminum production. It has an abundant carbon source and a unique graphitic carbon layer structure, making it a valuable waste for recycling. This paper uses alkaline and acid leaching methods to report a straightforward way of extracting recovered carbon (RC) from SCC as anode material for lithium-ion batteries (LIBs). The results show that alkaline and acid leaching conditions at 70 °C with 1 M NaOH and HCl solution individually in 6 h and a liquid-solid ratio of 20:1 can result in RC with up to 94.63% carbon content than 49.38% in SCC, exhibiting a typical graphite structure. SCC and RC materials are obtained after calcination at 400 °C in an inert atmosphere and used as anode materials (SCC-400 and RC-400). In this paper, The initial charging specific capacities are 490.0 mA h g-1, 195.4 mA h g-1, and 423.2 mA h g-1and initial coulombic efficiencies (ICE) are 67.8%, 78.9%, and 72.0% of RC-400, SCC, and SCC-400. RC-400 also shows excellent capacity retention and impedance values. This exciting finding provides a viable, non-hazardous, and resourceful method for treating and disposing of SCC from aluminum electrolysis.

A simple green method for in-situ selective extraction of Li from spent LiFePO4 batteries by synergistic effect of deep-eutectic solvent and ozone.

Efficient and clean extraction lithium (Li) from spent LiFePO4 batteries (LIBs) still remains a challenge. In this paper, a green deep eutectic solvent (DES) based on ethylene glycol (EG) and choline chloride (CC), combined with ozone (O3) from air source, realized highly selective leaching Li from LiFePO4 in situ for the first time. The influence of experimental parameters on Li and Fe leaching efficiencies (ηLi, ηFe) were studied by orthogonal and single-factor tests, and ηLi ≥ 92.2% while ηFe ≤ 1.6% were obtained under the optimal conditions (6 h, 20 g/L, 8EG:1CC, 40 °C). The impurity Fe in the filtrate was completely precipitated as amorphous FePO4·3H2O after heating (150 °C, 0.5 h), achieving a pure Li-solution. The leaching mechanism elucidated that the synergistic effect (acidification, replacement and oxidation reaction) between the DES and O3 determined the phase transition of Li and Fe, promoting the efficient selective extraction of Li and in-situ separation of Fe (FePO4). The average ηLi and ηFe were separately 85.4% and 2.0% after ten cycles of the 8EG:1CC, indicative of its' excellent reusability. Meanwhile, LiCl was recovered from the filtrate. This process avoided the use of strong acid/alkali and discharge of waste water, providing fresh perspectives on the green recovery of spent LiFePO4 batteries.

A review on takeaway packaging waste: Types, ecological impact, and disposal route.

Rapid economic growth and urbanization have led to significant changes in the world's consumption patterns. Accelerated urbanization, the spread of the mobile Internet, and the increasing pace of work globally have all contributed to the demand for the food takeaway industry. The rapid development of the takeaway industry inevitably brings convenience to life, and with it comes great environmental pressure from waste packaging materials. While maintaining the convenience of people's lives, further reducing the environmental pollution caused by takeaway packaging materials and promoting the recycling and reuse of takeaway packaging waste need to attract the attention and concern of the whole society. This review systematically and comprehensively introduces common takeaway food types and commonly used packaging materials, analyzes the impacts of discarded takeaway packaging materials on human health and the ecological environment, summarizes the formulation and implementation of relevant policies and regulations, proposes treatment methods and resourceful reuse pathways for discarded takeaway packaging, and also provides an outlook on the development of green takeaway packaging. Currently, only 20% of waste packaging materials are recycled worldwide, and there is still a need to develop more green takeaway packaging materials and continuously improve relevant policies and regulations to promote the sustainable development of the takeaway industry. The review is conducive to further optimizing the takeaway packaging management system, alleviating the environmental pollution problem, and providing feasible solutions and technical guidance for further optimizing takeaway food packaging materials and comprehensive utilization of resources.