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This study examines the domestic solid waste management system in the LATAM region, using the city of Guayaquil in Ecuador as a case study. Through the life cycle assessment (LCA) methodology, the study compares domestic and external recycling processes, evaluating their effects on global warming potential, fossil resource scarcity, and terrestrial ecotoxicity. The results reveal that increasing recycling rates significantly reduces environmental impacts, with domestic recycling offering slightly higher environmental benefits than external options. A demographic analysis using machine learning techniques identifies distinct patterns of waste generation across different population clusters, highlighting the need for tailored waste management strategies. The study also emphasizes the importance of accurate local data and the integration of recycling initiatives with market realities, particularly in the light of policies mandating recycled content in products like PET bottles. A sensitivity analysis of the waste recovery indicator (WRI) demonstrates the potential for substantial environmental and economic benefits with higher recycling rates. The findings suggest that, to advance towards a circular economy, Latin American cities like Guayaquil must enhance their recycling infrastructure, refine waste management policies, and focus on demographic-specific strategies. This research contributes to the broader understanding of sustainable waste management in developing regions, offering insights for future policy and infrastructure development. [ABSTRACT FROM AUTHOR]

Over the past decades, the use of polyethylene terephthalate (PET) has seen significant growth, particularly in the packaging industry. However, its long decomposition time poses serious environmental challenges. The aim of this research was to develop a process for the foaming of large quantities of recycled PET (rPET) using endothermic and exothermic foaming agents. Various formulations with different ratios of endothermic and exothermic foaming agents were prepared, as well as their mixtures. The study found that the endothermic–exothermic hybrid foaming process resulted in a finer cell-size distribution and enhanced mechanical properties, making the foams highly suitable for widespread applications. The results support the potential use of exothermic foaming agents as nucleating agents in a hybrid foaming system. In particular, the ratio of 3% endothermic and 1% exothermic foaming agents proved optimal in terms of achieving a balance between porosity and mechanical strength, thereby enabling broad industrial applicability. [ABSTRACT FROM AUTHOR]

With the recent ban on the production and use of long-chain perfluorinated compounds, the development of alternative approaches to prepare liquid-repellent surfaces that avoids the use of such compounds has become an urgent issue. We have succeeded in the development of fish-mimicking hydrophilic transparent hydrogel-based films with long-lasting anti-oil adhesion properties. Such films could be prepared by simply mixing poly(vinylpyrrolidone) (PVP), nanoclay particles (NCPs), and a waterborne aminosilane (AOS) using an integral blend (IB) method. When submerged in water, these films displayed underwater superoleophobicity (advancing and receding contact angles (CAs) of diiodomethane were ~171°/~163°) with low CA hysteresis (less than 8°), because the hydrophilic nature of the films promoted the formation of a thin layer of adsorbed water on the topmost film surfaces, similar to fish scales. Furthermore, when our films were coated onto the inside of poly(ethylene terephthalate) (PET) bottles and pre-wetted using 80 °C hot water vapors, these film surfaces could effectively repel various oils and were able to maintain their oil-repellent properties for more than 5 weeks. These water-driven, non-perfluorinated transparent hydrogel-based films are expected to increase recycling of PET bottles for oils that are generally incinerated or landfilled. [ABSTRACT FROM AUTHOR]

This article discusses the impact of human-caused climate change on tree mortality and biome shifts. Research conducted in the Sahel region of Africa found that temperature and rainfall were the main factors contributing to tree mortality, with one in every five trees dying from 1954 to 1989. Climate change has also caused biome shifts in various ecosystems worldwide. The article emphasizes the need to reduce carbon pollution and take action at all levels to address climate change. It also highlights the negative environmental impacts of excessive material consumption and the importance of adopting sustainable practices. The Paris Agreement and policies promoting renewable energy and greenhouse gas reductions are mentioned as steps towards halting climate change. The article concludes by emphasizing the importance of individual actions in minimizing material consumption and living simply to protect the environment. The given text provides a list of references and citations from various sources related to climate change, environmental impact, and related topics, which can be valuable for library patrons conducting research on these subjects. [Extracted from the article]

In the United States, polyethylene terephthalate (PET) bottle collection rates have not increased in a decade. Recycling rates remain abysmal while industry commitments and policy targets escalate the demand for recycled plastics. We investigate the PET bottle recycling system, where collection is a critical bottleneck and recycled PET supply is not meeting the expected demand. We characterize demand for recycled PET (R‐PET), analyze scenarios of expanding deposit return systems (DRS), and quantify cost barriers to improving PET bottle recycling. We find that a nation‐wide DRS can increase PET bottle recycling rates from 24% to 82%, supplying approximately 2700 kt of recycled PET annually. With stability in demand, we estimate that this PET bottle recycling system can achieve 65% bottle‐to‐bottle circularity, at a net cost of 360 USD/tonne of PET recycled. We also discuss environmental impacts, stakeholder implications, producer responsibility, and complimentary policies toward an efficient and effective recycling system. [ABSTRACT FROM AUTHOR]

Nowadays, waste management is gaining popularity to reduce the environmental impact made by human beings. There is a dire need to decrease the pollution caused by plastic materials. A gradual rise in the demand for polyester bottles has generated a need to recycle these materials. In the present work, an aromatic amine (4,4′‐(1,4‐phenylenebis(1,3,4‐oxadiazole‐5,2‐diyl)) dianiline) was prepared from the polyester bottle waste. The successful synthesis and chemical structure of the amine was confirmed by various characterization techniques such as Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR), and 13C NMR. The amine was diazotized and coupled with H‐acid (4‐amino‐5‐hydroxy‐2,7‐naphthalene disulfonic acid)‐treated wool fabric to generate acid dye in situ on the fabric. The coloration (L*, a*, b*, and K/S) and fastness properties of dyed wool were evaluated, and the samples were further analyzed for antibacterial and UV‐protective properties. The dyed wool was also characterized by FTIR to confirm the presence of the aromatic group of the dye. The introduction of dye structure on the wool increased the thermal stability of the fabric, which was confirmed through thermogravimetric analysis analysis. Antibacterial activity (>70%) and excellent UV protection were retained by dyed wool after 20 washes. Furthermore, the dyed wool was found nontoxic under the cytotoxicity evaluation test. [ABSTRACT FROM AUTHOR]

Amongst all synthetic polymers used in the clothing industry, polyethylene terephthalate (PET) is the most widely used polyester, its fibres representing half the total PET global market (in comparison bottle PET being less than a third). Compared to bottle PET, the recycling of fabric PET fibres represents a challenge, both due to intrinsic structural differences (chain length and crystallinity) and to the presence of various additives (dyes, protection or finishing agents). Effective waste management requires addressing these additives through elimination or recycling processes. This review article aims to give an overview about all the existing means to recycle PET fibres. Textile recycling encompasses primary (closed-loop), secondary (mechanical), tertiary (chemical), and quaternary (incineration with energy recovery) processes. Mechanical recycling faces challenges due to PET's characteristics, including lower molecular weight and additives. Chemical recycling, particularly solvolysis processes (hydrolysis in neutral, acidic, or alkaline media, alcoholysis, glycolysis, aminolysis or enzymatic hydrolysis), offers a more advanced approach and will be described in detail, focusing both on the specific recycling of fibres when available and enlightening the advantages and drawbacks of each method. To discuss the environmental impact of each process, a quantitative analysis was conducted by defining the experimental domain represented by the temperature range and reaction time, and then calculating the energy-saving coefficient, as a green metric adapted to the diversity of textile PET recycling processes and data provided in the literature. This coefficient allows for discussing the relevance of using complex or non-renewable catalysts in processes, the positioning of enzymatic pathways, and the choice of reaction mechanisms applicable to the industry. A prospective approach was employed to identify key criteria for future advancements in green recycling. Subsequently, a comparative analysis of depolymerisation methods will be presented within the context of sustainable development goals (SDGs), green chemistry, and green metrics. Finally, using ε factors, this analysis will facilitate the detection and highlighting of pathways that show the most promise in terms of greening PET recycling. [ABSTRACT FROM AUTHOR]

Chemical activated carbons (PET‐H2SO4 and PET‐KOH) were prepared from post‐consumer polyethylene terephthalate (PET) wastes using pyrolysis under moderate reaction temperatures by changing pyrolysis time and chemical activating agents. The produced carbons were characterized and tested in adsorption reactions of manganese, chromium, and cobalt ions in aqueous solutions. Results showed a high percentage removal of these inorganic ions from water: 98 % for Mn2+, 87 % for Cr3+, and 88 % for Co2+. Freundlich isotherms gave a better fit to the experimental data obtained with good correlation coefficient values in the range of 0.99‐1 compared to other isotherms. The pseudo‐second order kinetic model best described the chemical adsorption process as an exchange of electrons between the carbon and inorganic ions in solutions. The diffusion models showed that the process is controlled by a multi‐kinetic stage adsorption process. In summary, this work demonstrates that the production of activated carbon from PET waste bottles is a potential alternative to commercial activated carbon and can be considered a sustainable waste management technology for removing these non‐biodegradable plastic wastes from the environment. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of water surface evaporation abatement and water saving benefits under different floating coverage conditions, PE bottles, HDPE balls, and plastic film panels were used as test materials, and three different water surface coverage rates were set to carry out two consecutive annual non-glacial large-scale evaporation pool tests in the central arid zone of Ningxia, to comparatively analyze the evaporation abatement rates, water surface temperatures, changes in water quality, and water-saving costs and benefits of different covering materials and coverage rates. The results show that: the evaporation abatement rate of covering materials tends to increase from April to June, and tends to decrease from July to October; under the same conditions, the evaporation rate of the three types of cover of HDPE balls is 42.14%, 56.56%, 70.15%, which is significantly higher than that of PE bottles and plastic film panels; with the increase of the coverage rate of the material, the water body warms up more obviously, and plastic film panels have the greatest impact on water temperature, followed by HDPE balls, and PE bottles; no toxic substances were found in the covered water body and the water quality is stable and getting better. Under the same coverage, the water saving cost of HDPE balls is the lowest, and that of plastic film plates is the highest: with the same coverage material, 50% coverage is the lowest, 75% coverage is the highest; the value of direct benefits of the three materials to eliminate water surface evaporation is negative, but taking into account the indirect benefits of the case, if HDPE balls are used to cover 10 000 m² of water surface, the lifetime coverage rates of 50%, 75%, and 90% can realize positive benefits of 259 400 yuan, 274 100 yuan, and 360 600 yuan, respectively. After a comprehensive consideration of water-saving effect, water-saving costs and benefits, HDPE ball is identified as the water-saving material that can be used to reduce water surface evaporation in arid areas. [ABSTRACT FROM AUTHOR]

In 2022, 150 million tons of glass was produced globally, and approximately 47% of that amount was glass hollowware for tableware and food, beverage, and cosmetics packaging. Glass is considered one of the most recyclable materials as its properties and performance do not degrade upon reheating and reforming; yet only 21% of global production is recycled. The most recycled type of glass is soda–lime silicate bottle glass based on its widespread availability and its ability to accommodate higher levels of contamination compared to flat glass and specialty glass. Bottle glass manufacturers melt glass batch that is 10%–60% recycled glass cullet, limited only by the availability of pristine glass cullet that is free of contaminants such as plastic, metal, and organic material. Increasing rates of recycled content in glass manufacturing is stymied by the lack of a supply chain to deliver high quality glass cullet to manufacturers, as well as risk of material incompatibility and contamination. In this work, post‐consumer glass bottles of different colors, shapes, and brands were analyzed for chemical composition and thermal properties to quantify variation across five major color families: clear, blue, amber, forest green, and emerald green. This work shows that post‐consumer bottles of different colors and brands can be remelted without risk of material incompatibility and presents various processing methods to control color homogeneity in glass produced exclusively from mixed color cullet from recycled glass bottles. [ABSTRACT FROM AUTHOR]

Growing industrialization and population deposit huge amounts of waste materials into nature every day. Environmental pollution is the biggest threat to life on earth, and one of the major polluters of nature is the throwaway plastic bottles made from polyethylene terephthalate (PET), a harmful fossil fuel/petroleum-based material. This review focuses on the recent development of recycling techniques of PET waste and their potential applications including fiber production, nanofibrous membrane, air filtering materials, water filtering materials, reinforced concrete formation, energy harvesting etc. In addition, the two most promising methods for recycling: chemical recycling and mechanical recycling are discussed. The most appropriate technologies and waste disposal procedures are suggested for energy harvesting based on the socio-economic aspects of the problem. The recent progress of this topic has been discussed. The prospect of these recycled bottles has been mentioned at the end of the article. [ABSTRACT FROM AUTHOR]

The recycling and proper management of PET bottles is needed to avoid plastic pollution, as well as to achieve a plastic circular economy. In this study, we examined the recycling system of PET bottles and their material flows by life cycle, from production to recycling and disposal under different scenarios with reduced consumption for PET bottles. In Korea, PET bottle recycling has been managed by the extended producer responsibility system since 2003. As of 2021, annual usage of PET bottles per capita in Korea was estimated to be approximately 6.5 kg. The recycling rate of PET bottles after collection was determined to be 79% in 2021. However, recycled PET (or r-PET) from mechanical recycling is mostly used in low-grade PET applications such as short fibers, bands, and sheets. More than 112 thousand tons of r-PET chips would be needed to meet the 30% recycled content requirement in PET bottles in 2030 by regulation. Thus, there is an urgent need for high-quality secondary raw materials (i.e., food-grade) by adopting advanced sorting and recycling technologies for PET bottles with recycled content. PET bottle-to-bottle recycling practices can ensure the production of high-quality recycled materials and move Korea toward a plastic circular economy. [ABSTRACT FROM AUTHOR]

Novel catalysts for recycling PET bottles into monomers have been developed by depositing zinc onto the surface of SBA-15, mitigating ZnO catalyst agglomeration in glycolysis separation processes to enhance reaction yields. Various zinc compounds (Zn(OAc)2, ZnCl2, and ZnSO4) were employed as substrates for catalyst design on the porous, high-surface-area material SBA-15 via impregnation. The presence of distinct Zn species on SBA-15 was confirmed through XRD and EDS analyses. The acidity of the catalyst, a crucial factor in the PET glycolysis process, was assessed using different Zn-containing precursors. NH3-TPD measurement has revealed the highest acidity in ZnCl2, followed by Zn(OAc)2 and ZnSO4, respectively. Glycolysis reactions with a PET:EG ratio of 1:5 and a 1% catalyst at 200°C for 2 hours revealed the catalytic efficacy of zincdeposited compounds in the sequence ZnCl2 > Zn(OAc)2 > ZnSO4. Surprisingly, the ZnCl2 catalyst produced the highest yield of bis-2-hydroxyethyl terephthalate (BHET) at 75% and displayed exceptional recycling capability over three cycles, contributing significantly to resource recovery objectives aligned with the Sustainable Development Goals (SDGs). [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Solidaria is the property of Universidad Cooperativa de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • The deposit-refund system enables the bottle-to-bottle high value recycling of PET. • High value recycling reduces GHG emissions and comprehensive environmental impact. • Reducing energy consumption and increasing yield are important cut-in points. Polyethylene terephthalate (PET) is a widely used packaging material and has high value in recycling. However, under China's dominant informal recycling system, most PET bottles are downcycled into fibers. The deposit-refund system (DRS) is considered a feasible mechanism to facilitate the high-value recycling of PET bottles. To comparatively evaluate the environmental performance [reduction of greenhouse gas (GHG) and pollutant emissions] under different scenarios using life cycle assessments, including the current system based on informal recycling, an improved system with a larger contribution from the source separation of municipal solid waste, and evolving systems with DRS application, five scenarios were set up. The DRS can reduce GHG emissions and the comprehensive environmental impact by 0.538 kg CO 2 /kg PET bottles and 1.73 × 10−3 PE/kg PET bottles, respectively, compared to informal recycling. It can be concluded that the DRS-based recycling approach and the bottle-to-bottle recycling provide the substantial emission reduction potential of GHGs and pollutants. [ABSTRACT FROM AUTHOR]

This paper is about the development of a hybrid renewable energy–powered Laboratory–Scale plastic bottle waste converter for the conversion (pyrolysis) of plastic (PET) bottle wastes into useful petroleum products such as Diesel, kerosene, gasoline, etc. Waste plastic disposal and indiscriminate use of fossil fuels have caused environmental and health concerns in our societies. This is not unconnected with the ever–increasing consumption of products packaged in plastics by the teeming population the world over. Plastics are non–biodegradable products that pollute our environments, clog our canals and drainages, and eventually end up in the seas where they pollute and affect marine ecological systems. The process of converting waste plastic bottles into useful petroleum products is one of the viable solutions for the recycling of plastic bottle waste and turning the problems of plastic bottle careless disposals into an opportunity to make wealth from waste and also save the ecosystem. Heat is provided externally to the heating chamber that runs at high temperatures in the absence of oxygen by a DC heating element. The waste plastic bottles are shredded to reduce their volume–to–weight ratio and filled into the heating chamber where it is subjected to excessive heat to depolymerize, pyrolyze, and thermal cracking. The resulting gases are passed through a condenser to obtain different products such as petrol, kerosene, diesel, etc depending on the operating temperature of the chamber. The fuel obtained is useful in firing boilers and furnaces directly without any analysis or purification. It can be scaled up for commercial applications. [ABSTRACT FROM AUTHOR]

Under the era of circular economy, the deposit-refund system (DRS) for e.g. polyethylene terephthalate (PET) is thought to be a good choice to achieve a more structured plastic recycling. The present research has the aim to make a comprehensive description and a practical guideline in order to evaluate how collection and separation system influence the quality and efficiency of mechanical recycling of PET. The DRS has been symbolized by manually collected bottles with (BCL) and without (B) caps and labels. Samples have been given from the selective income (SI) and the sorting residue (SR) of a manual selective waste sorting plant and PET fraction of refuse derived fuel (RDF). Based on preliminary qualification results such as melt flow indices (MFI), PET bottles are worth selecting into the main colours like water clear, blue, and all the others together, referred to as PET-A, PET-B, and PET-D fractions of the sorting plant. The SR seemed to be a beneficial raw material for PET recycling as both mechanical and rheological properties were proper enough. PET separated from the Mechanical Biological Treatment (MBT) plant as RDF showed the worst processing and mechanical properties, but both can be improved with deeper precleaning. X-ray tomography (CT) scans have shown a correlation between the source of waste and the gas void structure which influence the macroscopic mechanical properties. [ABSTRACT FROM AUTHOR]

Summary: The release of bisphenol A (BPA) from polyethylene terephthalate (PET) bottles in non‐carbonated water was investigated in this work through migration and leaching tests. Several types of PET bottles approved and used by several Romanian non‐carbonated mineral water brands were tested in this work. It was highlighted that both the storage temperature and the storage time of bottled water in PET bottles influence the degree of PBA release. Thus, increasing the temperature and storage time favours the release of BPA from PET. The higher the storage temperature, the higher is the diffusivity of BPA. The degree of BPA release is also closely related to the brand of PET. This could be related to the degree of contamination of the raw material in the manufacturing process of PET bottles or during their recycling. The physico‐chemical characteristics and stability of PET bottles in different environmental conditions can also influence the release of BPA from them. The leaching tests confirmed the potential for BPA contamination of long‐term non‐carbonated water bottled in PET bottles. [ABSTRACT FROM AUTHOR]

Water bottles are widely used in the Gulf countries. One estimate indicates that the water bottle usage in the United Arab Emirates (UAE) may reach up to 250 L of water per person annually. Generally, the water bottles are made of polyethylene terephthalate (PET), a recyclable material. Because of the non-availability of a powerful incentive system, these recyclable water bottles are often disposed of in landfills. This paper proposes a feasibility study of building a Deposit–Refund System (DRS) to encourage the closed-loop recycling of 0.5 L PET water bottles in the UAE waste disposal system. Water bottles are collected by a reverse vending machine (RVM) and recycled to produce PET bottles, and the proposed system will reward consumers with 0.04 United Arab Emirates Dirham (AED) per deposited water bottle. Additionally, this study calculates the cost of 100% virgin polyethylene terephthalate (vPET) and 60% recycled polyethylene terephthalate (rPET) bottles based on the UAE population, data obtained from local water bottle companies, and existing research. Adopting this DRS will cut down on waste, protect the environment, improve the manufacturing process of water bottles, and boost the local economy. [ABSTRACT FROM AUTHOR]

Copyright of Nachhaltigkeitsrecht is the property of Verlag Oesterreich GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Baseline data on plastic landing by fishers and monitoring of this is important in evaluating the success of plastic waste management efforts. This study investigated plastic and fish landed by beach seine fishers in Ghana together with the rate of plastic deposition on an adjoining beach. Plastic constituted 31.6% of the total catch and 41.7% of the fish landed by weight. There were significant differences between the average weight of fish (139.58 ± 53.6 kg) and plastic (65.73 ± 14.6 kg) landed per fishing session and the catch per unit effort of fish (183.4 ± 76.7 kg/day) and plastic (88.4 ± 35.2 kg/day). The mean weight of plastic landed per fishing session was higher than the mean weight of each of the 26 species of fisheries. The rate of plastic deposition on the beach was 8.1 ± 2.5 plastic items per m2 per tidal cycle or 0.35 ± 0.11 kg plastic per m2 per tidal cycle with food packs and tableware dominating the deposited plastic. The results suggested ongoing water sachets and plastic bottle recycling in Ghana are yielding results and calls for targeted efforts in plastic food packs and tableware management. [ABSTRACT FROM AUTHOR]

Itinerant Roma migrants travelling from Eastern European countries have featured across the European Economic Area (EEA) since the European Union's eastward expansions in 2004 and 2007. Being unskilled, many Roma migrants engage in casual work and street work such as playing music, selling magazines, collecting and recycling bottles and cans, and begging, making them conspicuously visible in countries with public welfare services and low poverty levels. Citizens of EEA countries can enter and stay legally in other countries in the EEA for up to three months, after which they must register as workers or jobseekers, and generally leave. It is well documented how the countries Roma citizens of EEA countries travel to have enacted migration control measures, often in the form of complex and fine-grained regulations, that exclude them from public welfare services. This is also true of the Nordic countries, such as Norway, where they coincide with universalistic welfare states aiming to cover everyone living in their territories with the same benefits and services. In the Nordic countries, as in other countries, service provision for Roma migrants is largely in the hands of non-governmental organisations, many of them diaconal organisations running emergency shelters, soup kitchens, and other humanitarian services to alleviate suffering for people at the margins of the welfare state. The diaconal organisations also engage in case work and advocacy work to ensure the realisation of the Roma migrants' rights. Many of the organisations depend on public grants, making their relationship to the welfare state ambiguous. This article investigates Christian social practice in the form of diaconal engagement for Roma migrants in Oslo, Norway at the intersection of migration control, the universalistic welfare state, and the theological underpinnings of the organisations. [ABSTRACT FROM AUTHOR]

Currently, human activity has a substantial impact on the environment, and we are responsible for determining what it will look like in a few or a dozen decades. Numerous IT solutions are being developed to reduce the negative influence on the environment. In particular, the main problem is the amount of plastic found in circulation and its recycling. Unfortunately, only few solutions exist that, on the one hand, support the reuse of the raw material and, on the other hand, give tangible benefits to users. In this work, we present a blockchain-based system for monitoring the recycling process of plastic bottles. The solution was described by technical, social, and performance characteristics. It should be emphasized that the adopted features of the new blockchain, such as a simplified code or complete decentralization, distinguish the solution from those currently created. Moreover, performance and fraud detection tests were performed. The results present that the solution for a PoW difficulty level of 3 still achieves decent times when generating a block with transactions (from the point of view of the recycling process). In addition, fraud detection tests have proven the ability to detect forged transactions. The outcomes from performed experiments show that the proposed concept can be used as an efficient and fraud-resilient solution in the case of the plastic recycling process. [ABSTRACT FROM AUTHOR]

In this work, post-consumer poly(ethylene terephthalate) (PET) bottles were gathered, separated from other materials, and re-extruded. In order to evaluate the effect of re-extrusion on the structure of PET, Fourier transform infrared spectroscopy was utilised. No significant effect of the re-extrusion process on the structure of the PET sample was noticed. Obtained samples were also characterised by differential scanning calorimetry (DSC) in order to determine characteristic thermal transitions of PET. DSC results indicated the influence of re-extrusion; extruded PET started to melt at lower temperatures, and the crystallisation of re-extruded PET took place at significantly higher temperatures in comparison to PET. Likewise, thermogravimetric analysis (TG) was used to evaluate the effect of re-extrusion process on the thermal stability of samples. TG analysis revealed that the re-extrusion process had no effect on the thermal stability of the investigated PET samples. Finally, the activation energy of thermal degradation of the investigated samples was calculated using iso-conversional Flynn-Wall-Ozawa and Friedman method. Consequently, higher activation energies were noticed for the re-extruded PET sample in comparison to the PET bottle sample, which is a good argument in support of PET bottle recycling. [ABSTRACT FROM AUTHOR]

As a result of the developing industry and growing population a significant increase has happened in the volume of waste plastic bottles, consequently, their disposal has become a major concern. One possible recycling method is to use them in soil reinforcement applications. In this study, the benefit of the soil-filled Polyethylene Terephthalate (PET) bottles for soil reinforcement was examined by a series of laboratory-scale tests. Three sizes of bottles with and without peripheral polypropylene (PP) belt were considered. Also, an extra layer of geogrid over bottle reinforced zone was examined in limited tests. The results showed bearing capacity improvement in all reinforcing arrangements, which increases as the bottle size increases. Further improvement happened when PP belt was provided, superior to the performance of a single layer of geogrid for all three bottle sizes. Eventually, an extra layer of geogrid over the bottle reinforced zone delivered a stiffer response and higher bearing pressure at much lower displacement, favorable in situations where soil settlement is of utmost importance. The combined use of soil-filled bottles and a single layer of geogrid may eliminate the demand for multilayer geosynthetic reinforcement, and also be a possible alternative for waste PET bottle recycling programs. [ABSTRACT FROM AUTHOR]

According to 2018 data from the National Association of PET Container Resources, it is estimated that the recycling rate of the poly(ethylene terephthalate) (PET) bottle in the US is 29%. Trailing this figure is the amount of recycled PET bottles that are utilized for future applications, which is estimated at 20%. Over the previous decade, both values have remained relatively unchanged due to the dynamics of various factors. Ironically, one contributing factor is the mechanical recycling process itself, particularly if the material has been previously exposed. Repeated exposure to mechanical recycling can degrade the properties of the PET, limiting future utilization and in severe cases, destining the material for the landfill. Given the importance of the material properties to the proper functioning of the PET in a bottle application, it is imperative to understand how the properties of the material change when subject to repeated mechanical recycling. The aim for this research was to investigate how the properties of a virgin, bottle grade PET change when subject to a repeated step of the mechanical recycling process, melt extrusion. After each successive extrusion, changes in the thermal, rheological and mechanical properties were measured and compared to the virgin values. [ABSTRACT FROM AUTHOR]

Despite ecological importance, the feeding ecology of the large calanoid copepod, Neocalanus cristatus is little known, as its ingestion rate under experimental conditions consistently falls short of its metabolic demand. The conventional incubation bottle size (~ 2 liters) used in previous studies may have affected its feeding behavior. Here, we examined the effect of bottle size (2.4 vs. 13liters) and copepod density on the feeding of N. cristatus Stage C5. Under similar copepod density (0.4 ind. L−1) ingestion rates decreased significantly for tests conducted in small bottles and thus, small bottles inhibited copepod feeding. In experiments with large bottles, ingestion rates were highest in the single‐individual treatments (1 ind. 13 L−1), decreasing exponentially to < 1% of the maximum ingestion rate with increasing copepod densities (up to 20 ind. 13 L−1). Considerable food limitation occurred in the higher copepod density treatments with lower initial prey allocation per individual. Moreover, in the single‐individual treatments, clearance rates on naked ciliates (11–20 L ind.−1 d−1) were remarkably higher than in multiple‐individual treatments. Grazer–grazer interaction, thus, interfered with copepod feeding on microzooplankton in multiple‐individual treatments. The ingestion rate in the single‐individual treatments (62–102 μgC ind.−1 d−1) exceeded the daily metabolic requirement; feeding rates noted in previous studies were, thus, underestimations, affected by bottle size and copepod mutual interference. Efficient feeding by N. cristatus on naked ciliates emphasizes the importance of the ciliate‐copepod link in the grazing food chain in the subarctic Pacific. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) continues to be a major challenge in almost every country. In Indonesia alone, approximately 64 million tons of MSW are produced on an annual basis. While polyethylene terephthalate (PET) bottles account for 12% of all plastic products, the waste is not well managed. Many stakeholders are involved in PET bottle waste recycling but no forum for stakeholders has been established. In this study, the aim is to identify an acceptable system for PET bottle waste, to determine the role and function of each stakeholder, and to propose a framework under the perspective of public-private partnerships. The study's novelty is the elaborate roles and schematic framework for various stakeholders in PET bottle waste. The aim is to identify an acceptable scheme for PET bottle waste and determine each stakeholder's role and function. Data was generated from electronic databases (2017 to December 2021) a systematic literature review methodology followed by Preferred Reporting Items for Systematic review. The data were analyzed by the Meta-Analysis (PRISMA) approach. This study found that the laws and regulations for waste management in Indonesia are not suitable for dealing with PET bottle waste, and the government carries out limited tasks and dedicates few resources to managing the waste. A public-private partnership framework was proposed to divide the role, commitment, goal, and activities of each stakeholder to properly manage PET bottle waste. [ABSTRACT FROM AUTHOR]

The demand for recycling high‐density polyethylene (HDPE) utilizing mechanical recycling technologies is currently felt strongly by both society and industry. However, thermal oxidation of the polymer during the recycling process may lead to irreversible changes in the material properties of recycled high‐density polyethylene (rHDPE). The effects of mechanical recycling on the optical characteristics and microstructure of rHDPE pellets and bottles were investigated in this study. The results revealed that the apparent color of the rHDPE became more yellow and gray compared to the virgin HDPE (vHDPE), and showed a signal at 670–680 nm in the solar reflectance spectrum. The thermal oxidation of rHDPE considerably raised the absorption intensities of carbonyl, ester, and hydroxyl groups in attenuated total reflection Fourier transform infrared spectrum. In addition, the presence of carbonyl and hydroxyl unsaturated chemicals might make it challenging to recognize the distinctive peaks of vHDPE in the ultraviolet–visible diffuse reflectance (UV–Vis‐DIR) spectra at wavelengths less than 400 nm. Thermal oxidation of rHDPE was also confirmed in the COH, CO, and OCO valence structures of C1s and O1s. A characteristic valence band (VB) profile at 25 eV can be used as the recognizable information for the oxidation of rHDPE. The microstructure of the surface of rHDPE pellets exhibited rough and uneven morphological defects. The higher recycled content made rHDPE bottles' surface morphology rougher and their cross‐section microstructure thinner and more porous than vHDPE bottles. [ABSTRACT FROM AUTHOR]

• DRS performance is driven by diverse social, economic, and legislative factors. • Higher deposit values and more return points boost return rates in successful DRSs. • DRS supports the EPR principle, aiding compliance with plastic waste legislation. • Balancing environmental gains and transportation emissions is key to DRS sustainability. • DRS design must consider social factors for equitable participation in recycling. This critical review assesses the implementation and impact of Deposit Return Schemes (DRSs), also referred to as 'Deposit Refund Systems' and 'Deposit Return Systems' in international contexts, focusing on plastic beverage bottles. The review explores the multi-dimensional challenges that shape effective DRS implementation. A total of 143 peer-reviewed articles and grey literature studies were analysed based on DRS definitions, scope, year of implementation, materials involved, and impacts across multiple dimensions (technical, social, economic, regulatory, and environmental). Emphasising Europe, the study outlines the multi-dimensional challenges and opportunities associated with DRSs. Key findings highlight the critical importance of balancing redemption locations, deposit values, and public awareness, as reflected in varying return rates in different countries. While industry stakeholders advocate for standardising DRS models to maximise economic and technical value in the plastic bottle value chain, significant European-wide and regional-specific challenges such as harmonizing legal requirements, potential trade-offs, and addressing environmental and transportation costs, persist. This underscores the ongoing need for evaluation and refinement of DRS implementation strategies within evolving waste management practices. As the first of its kind, this study underscores the necessity for future research to inform the sustainability assessment of DRS, policy development, and efforts to promote social accountability. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Balkan & Near Eastern Journal of Social Sciences (BNEJSS) is the property of Balkan & Near Eastern Journal of Social Sciences (BNEJSS) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As part of a project that aims to provide people with disabilities with simple assistive devices in Colombia, the possibility of creating a PET filament that can be printed by Fused Deposition Modelling (FDM) from beverage bottle waste was investigated, with the aim to remain as simple as possible in terms of plastic collection, sorting, processing, and printing. Recycled PET filaments were thus produced by extrusion from collected PET bottles, with the potential addition of HDPE, which comes from caps and rings. The microstructure, mechanical performance, and printing quality of parts produced with these filaments were investigated in comparison to commercial PET virgin and recycled filaments. HDPE presence as an immiscible blend did not affect the ease of extrusion or the quality of the printing, which were all satisfactory. In some conditions, the addition of 5 wt% of HDPE to recycled PET had a toughening effect on otherwise brittle samples. This behavior was attributed to the presence of elongated HDPE inclusions resulting from shear forces induced by the layer-by-layer printing, provided that the interface temperature remained high between layer depositions. This confirms that the mechanical performance of recycled PET is very sensitive to the processing conditions, especially in the case of 3D printing. Nonetheless, this low-cost process that did not require sophisticated compatibilization schemes allowed for the printing of parts with mechanical properties comparable to those obtained with high purity, commercially recycled filaments, opening interesting perspectives for a low-cost PET recycling process. [ABSTRACT FROM AUTHOR]

Cracking of polyester bottles and recycling the waste, which is of concern in the current research works have their roots in the environmental stress cracking and the physical structural analysis, which has been the subject of a huge number of research reports, that are collected in the present review. Polyesters are polymers of high importance in industry and academia, and amines are versatile chemicals that are used for different purposes. The reaction of polyester with amines has been used to reveal structure, improve the properties of products, convert polyesters waste into benign materials, enhance biocompatibility, and so on. The research works reported on the aminolysis of polyesters (PET, PCL, PLA, PTT, PBT, PHB, PEN, PEA) for structure and morphological determination, etching, and stress cracking are critically reviewed. The chemistry and mechanism of the reactions of aminolysis of an ester or a polyester are well documented, and a vast amount of useful information is available. There is a need for further research to answer the remaining questions on the intermediates. Solutions of amines act as environmental stress‐cracking agents, may induce crystallization, and probably it can dissolve and remove a certain amount of disordered regions as well. In the subject of stress cracking that can help the elucidation of the process of aging, it is not yet clear how cracks patterns and sizes (from nano up to micro size) observed on the surface of polyester products depend on the thermal and mechanical history of the samples, and it is not known how to produce cracked patterns according to a pre‐planned design on the surfaces of polyester articles. To make polyesters more useful and safe the structure must be revealed in order to get benefit from the structure–property relations. [ABSTRACT FROM AUTHOR]

• The technical performance of an improved mechanical recycling process is reported. • Regranulates from this process exhibit higher performance compared to the baseline. • It is demonstrated that the regranulates can be used in higher value applications. • The process is shown to be less negative in the economics and more self-sustaining. Packaging represents the largest fraction of plastic waste in Europe. Currently, mechanical recycling schemes are mainly focused on the recovery of rigid packaging (like bottles), while for flexible packaging, also called films, recycling rates remain very low. Existing mechanical recycling technologies for these films are quite basic, especially in the case of complicated post-consumer flexible plastics (PCFP) waste, leading to regranulate qualities that are often subpar for renewed use in demanding film applications. In this study, the technical and economic value of an improved mechanical recycling process (additional sorting, hot washing, and improved extrusion) of PCFPs is investigated. The quality of the four types of resulting regranulates is evaluated for film and injection molding applications. The obtained Polyethylene-rich regranulates in blown films offer more flexibility (45–60%), higher ductility (27–55%), and enhanced tensile strength (5–51%), compared to the conventional mechanical recycling process. Likewise, for injection molded samples, they exhibit more flexibility (19–49%), enhanced ductility (7 to 20 times), and higher impact strength (1.8 to 3.8 times). An economic assessment is made between the obtained increased market value and the capital investment required. It is shown that the economic value can be increased by 5–38% through this improved recycling process. Overall, the study shows that it is possible to increase the mechanical recycling quality of PCFP in an economically viable way, thus opening the way for new application routes and overall increased recycling rates. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)