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Microplastic pollution is a significant environmental issue caused by unsustainable plastic use and disposal. These tiny plastic particles (<5 mm) have been found in virtually every environmental compartment, and their environmental removal is currently deemed unfeasible. Microplastics have received a lot of attention over the past decade due to concerns over their ecological and health effects. However, limited research has been done on the management of microplastics. Microplastic pollution is directly related to total plastic pollution, so reducing environmental plastic waste is crucial for reducing microplastics. Overall plastic pollution can be reduced by different strategies including, effective plastic waste management encompassing the 4Rs (Reduce, Reuse, Recycle, Recover) along with upcycling, implementing policies that govern the entire lifecycle of plastics promoting a circular economy for plastics, enhancing treatment technologies and clean-up, creating public awareness and developing sustainable alternatives. However, the multifaceted nature of microplastic contamination cannot be properly addressed by employing these strategies independently, leading to the limited effectiveness of these strategies. Therefore, a multidisciplinary approach integrating the above strategies to limit the environmental plastic input and reduces the plastic waste already accumulated is crucial. This manuscript provides a framework for effective management of microplastics and provides comprehensive discussions of each strategy within the framework including the potential measures by governments, international organizations and the public to reduce plastic waste. Moreover, it provides recommendations for improving the legislative framework and identifies the research gaps in the microplastic clean-up technologies and sustainable plastic alternatives that need to be addressed to improve management of environmental microplastics. HIGHLIGHTS: Management of microplastics is dependent on the management of overall plastic waste. Policies and regulations should address both municipal and industrial plastic wastes Technologies for microplastics removal can improve plastic cleanup. International and industrial cooperation is crucial for reducing environmental MPs. Long-lasting solutions need a multidisciplinary approach. [ABSTRACT FROM AUTHOR]

The rapidly increasing production and widespread application of plastics have brought convenience to our lives, but they have consumed a huge amount of nonrenewable fossil energy, leading to additional CO2 emissions and generation of an enormous amount of plastic waste (also called white pollution). Chemical recycling and upcycling of waste plastic products (also called waste plastic refineries) into recycled monomers and/or valuable chemicals can decrease the dependence on fossil energy and/or reduce the emission of CO2, enabling the full utilization of carbon resources for the development of a circular economy. Polyesters, a vital class of plastics, are ideal feedstocks for chemical recycling due to the easily depolymerizable ester bonds compared to polyolefins. Among them, polyethylene terephthalate (PET) is the most widely used product, making its chemical recycling to a circular carbon resource a hot topic with significant concerns. In this feature article, recent progress in depolymerization of waste polyesters (PET and/or PET-containing materials) and the subsequent upgrading of depolymerized monomers (or intermediates) to valuable chemicals was reviewed and prospected. Newly reported technologies, such as thermal catalysis, photocatalysis, electrocatalysis, and biocatalysis, were discussed. The achievements, challenges, and potential of industrial applications of chemical recycling of polyesters were addressed. [ABSTRACT FROM AUTHOR]

Anaesthesiologists overwhelmingly favour pulse wave analysis techniques as their primary method to monitor cardiac output during high-risk noncardiac surgery. In patients with a radial arterial catheter in place, pulse wave analysis techniques have the advantage of instantly providing non-operator-dependent and continuous haemodynamic monitoring information. Green pulse wave analysis techniques working with any standard pressure transducer are as reliable as techniques requiring dedicated pressure transducers. They have the advantage of minimising plastic waste and related carbon dioxide emissions, and also significantly reducing hospital costs. The future integration of pulse wave analysis algorithms into multivariable bedside monitors, obviating the need for standalone haemodynamic monitors, could lead to wider use of haemodynamic monitoring solutions by further reducing their cost and carbon footprint. [ABSTRACT FROM AUTHOR]

Anaesthesia contributes substantially to the environmental impact of healthcare. To reduce the ecological footprint of anaesthesia, a set of sustainability interventions was implemented in the University Hospital Zurich, Switzerland. This study evaluates the environmental and economic implications of these interventions. This was a single-centre retrospective observational study. We analysed the environmental impact and financial implications of changes in sevoflurane, desflurane, propofol, and plastic consumption over 2 yr (April 2021 to March 2023). The study included pre-implementation, implementation, and post-implementation phases. After implementation of sustainability measures, desflurane use was eliminated, there was a decrease in the consumption of sevoflurane from a median (inter-quartile range) of 25 (14–39) ml per case to 11 (6–22) ml per case (P <0.0001). Propofol consumption increased from 250 (150–721) mg per case to 743 (370–1284) mg per case (P <0.0001). Use of plastics changed: in the first quarter analysed, two or more infusion syringes were used in 62% of cases, compared with 74% of cases in the last quarter (P <0.0001). Two or more infusion lines were used in 58% of cases in the first quarter analysed, compared with 68% of cases in the last quarter (P <0.0001). This resulted in an 81% reduction in overall environmental impact from 3 (0–7) to 1 (0–3) CO 2 equivalents in kg per case (P <0.0001). The costs during the final study phase were 11% lower compared with those in the initial phase: from 25 (13–41) to 21 (14–31) CHF (Swiss francs) per case (P <0.0001). Implementing sustainable anaesthesia interventions can significantly reduce the environmental impact and cost of anaesthesia. [ABSTRACT FROM AUTHOR]

As the world shifts towards renewable energy and more efficient energy storage systems, the demand for advanced materials that can support these technologies has increased. One such promising material class is High Entropy Alloys (HEAs). Unlike conventional alloys, which are typically composed of one or two principal elements, HEAs consist of multiple principal elements in near-equiatomic proportions. Their unique atomic structure, characterized by high configurational entropy, endows them with enhanced stability, tunability, and a high specific surface area—qualities that are highly desirable in supercapacitor applications. HEAs offer significant advantages as supercapacitor electrodes, including increased energy storage capacity, superior electrochemical stability, and the potential for synergistic effects that improve overall performance such as higher energy density, longer cycle life, and greater reliability. FeCoNiCuZn) 3 O 4 has been synthesized by utilizing multiple induction melting process in a quartz tube at 1100 °C , followed by ball milling in order to transform the small pieces into nanostructured powder. The highest specific capacitance obtained is 245.7 F g−1 at 1.5 A g−1 in three electrode measurement system. In addition, plastic biochar was prepared using pyrolysis techniques from plastic wastage. Moreover, it is utilized for supercapacitor application, which shows a maximum specific capacitance of 180 F g−1 at 1 A g−1 for three electrode system. The combing above two electrode materials, the fabricated asymmetric device shows a maximum specific capacitance of 58 F g−1 at 1 A g−1 for 3M KOH electrolyte with maximum specific energy of 23.44 Wh kg−1 at specific power of 1700 W kg−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tailored ZSM-5 additives were used for cracking dissolved plastics in vacuum gas oil. • 15% of the ZSM-5 additives were mixed with 85% equilibrium catalyst (E-Cat). • E-Cat + ZSM-5(50) (Si/Al = 50) has conversion of 83.7 % and light olefins yield of 35 %. • E-Cat + ZSM-5(75) (Si/Al = 75) has conversion of 81 % and light olefins yield of 38.4 %. • ZSM-5(75) is most effective for converting plastic in HVGO into light olefins. Typical cracking catalysts, called equilibrium catalyst (E-Cat) are ultra-stable Y (USY) zeolite often used with 15% commercial ZSM-5 zeolite additive (ZSM-5(COM)) to boost olefin yield. In this study, similar additive zeolites with different pore sizes and acidic character were synthesized by rapid ageing of precursor solution and used in the co-cracking of low-density polyethylene (LDPE) and heavy vacuum gas oil (HVGO). Three ZSM-5 zeolites additives with Si/Al ratio 25 (ZSM-5(25)), 50 (ZSM-5(50)) and 75 (ZSM-5(75)) were synthesized and combined with E-Cat to form E-Cat/ZSM-5(25), E-Cat/ZSM-5(50) and E-Cat/ZSM-5(75) respectively. The E-Cat/ZSM-5(50) has slightly better endothermic conversion (cracking) of a mixture of dissolved LDPE and HVGO into H 2 , C 1 to C 4 gases and C 2 -C 4 light olefins (total conversion of E-Cat 80.0%, E-Cat/ZSM-5(COM) 75.0% and E-Cat/ZSM-5(50) 83.7% respectively), with different gas, liquid and coke distributions. The E-Cat/ZSM-5(75) has 81% conversion, and highest yield of light olefins (38.4%). Structural (surface area, pore size) and chemical (acid sites) characteristics of the synthetized ZSM-5(75) zeolite explain the observed higher light olefin selectivity by different and competing catalytic routes. The ZSM-5(75) has demonstrated to be a good zeolite additive for converting dissolved plastic in HVGO into light olefins. [ABSTRACT FROM AUTHOR]

[Display omitted] • Radical reactions between biomass and plastic enhance oil production in HTL. • ▪OH radical from oxygenated biomolecule facilitate plastic polymer depolymerizing. • C 1 –C 4 radicals emitted from biomass and plastic polymer recombine as oil molecules. • Lipid and protein could lower the HTL temperatures for plastic polymers. • Feedstock blended ratio plays a crucial role in the reactions during coliquefaction. Recently, hydrothermal coliquefaction of biomass and plastic waste has attracted considerable research interest. However, there is a notable gap in understanding the fundamental reaction mechanisms between biomass and plastics during coliquefaction. This study focused on the coliquefaction of biomass model compounds and plastic polymers using ReaxFF molecular dynamics simulations under both subcritical and supercritical water conditions. Molecular-level tracking and probing of the reaction mechanisms between biomass model compounds and plastics were conducted to purposefully enhance oil production. The study observed related radical reactions between by-product molecules, with detailed mechanisms primarily involving (1) ▪OH radicals released by aqueous phase molecules from biomolecules, transferring as H 2 O molecules and facilitating plastic depolymerization, and (2) C 1 –C 4 radicals in the gaseous phase, emitted from biomolecule and plastic, colliding and subsequently recombining to form oil molecules. Moreover, the yield of multiple products from various mixtures were evaluated by considering the key reaction parameters including reaction temperature and feedstock blended ratio. An exploration into the effect of coliquefaction on oil yield was conducted to precisely identify the optimal coliquefaction conditions. The positive effect of coliquefaction was more pronounced between biomass model compounds and aromatic polymers compared to aliphatic polymers. Analysis of reaction mechanisms and product outcomes has shown that hydrothermal coliquefaction is a viable approach to improving oil production from multi-source organic solid waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe/Ni ratio and temperature have great influenced on the structure of CNTs. • DFT calculations are used to study the growth mechanism of CNTs. • The feasibility and mechanism of PVC removal by CNTs are investigated. Plastic waste pollution is the serious environmental problem, and catalytic pyrolysis of waste plastics is an effective way to solve this problem. Carbon nanotubes (CNTs) are prepared by catalytic pyrolysis of low-density polyethylene (LDPE) waste plastics by one-stage method using iron nitrate and nickel nitrate as catalyst. The growth mechanism of CNTs is analyzed in detail. TPO, XRD, SEM and Raman analyses show that increasing Ni content contributes to the production of CNTs with good morphology and high graphitization degree. While the increasing Fe content contributes to improving the yield of CNTs. The outer and inner diameters of the FeNi12-CNTs-800 are about 21 nm and 8 nm with the length of 18.9 μm, respectively. LDPE pyrolysis gases are analyzed to determine that the primary carbon source required for CNTs growth is C 2 H 4. The C 2 H 4 adsorption and decomposition processes on FeNi alloys are performed to reveal the growth mechanism of CNTs, based on density functional theory calculation. Three kinds of the growth models are proposed to explain the difference of the CNTs tubular shape. FeNi12-CNTs-800 are used to remove microplastics from wastewater due to existence of magnetic. PVC can be quickly removed from wastewater with removal of 100 % at 20 min. This study provides an effective way for recycling and treatment of waste plastic. [ABSTRACT FROM AUTHOR]

[Display omitted] • Through accurate material design and construction, seawater can completely replace scarce fresh water to obtain hydrogen energy: Seawater accounts for 96 %∼97 % of the world's water resources, and the use of seawater as a source of hydrogen will alleviate the problem of water shortage; The hydrogen production rates of g-C 3 N 4 /CdS/NiS in seawater and pure water for 5 h are 30.44 and 25.79 mmol/g/h, respectively. After 25 h, the hydrogen production rates are 16.17 mmol/g/h and 15.54 mmol/g/h, respectively; • This is a completely new design concept without sacrificing agents: The use of plastic hydrolysate as a sacrificial agent effectively reduces the pollution caused by other sacrifices, such as Na 2 S/Na 2 SO 3 , methanol, etc; • The mechanism of the whole coupling reaction is discussed and proposed: The photocharge transfer occurs between CdS and g-C 3 N 4 , the CB electrons of the g-C 3 N 4 are transferred to the CB of CdS. The electrons participate in the hydrogen evolution reaction at the reduction site of the NiS to produce hydrogen. The VB hole of CdS is injected into the VB of g-C 3 N 4. The hole will react with lactate in seawater solution to oxidize lactate to pyruvate, acetate and formate. Converting plastics into organic matter by photoreforming is an emerging way to deal with plastic pollution and produce valuable organic matter. Water shortage can be alleviated by using seawater resources. To solve these problems, we synthesize a ternary heterostructure composite g-C 3 N 4 /CdS/NiS. Heterojunctions are formed between graphitized carbon nitride (g-C 3 N 4), cadmium sulfide (CdS) and nickel sulfide (NiS), which effectively improve the problem of fast charge recombination of pure g-C 3 N 4 and CdS. The results of the g-C 3 N 4 /CdS/NiS photocatalytic tests show that the hydrogen production rates in seawater and pure water for 5 h are 30.44 and 25.79 mmol/g/h, respectively. In stability test, the hydrogen production rate of the g-C 3 N 4 /CdS/NiS in seawater and pure water is similar. This suggests that seawater can replace pure water as a source of hydrogen. While H 2 is generated, the lactate obtained by polylactic acid (PLA) hydrolysis is oxidized to form small organic compounds such as formate, acetate and pyruvate. Our study shows that g-C 3 N 4 /CdS/NiS can not only use seawater as a hydrogen source to produce H 2 , but also photoreformate plastics dissolved in seawater into valuable small organic molecules. This has a positive impact on the production and use of clean energy, as well as on plastic pollution and water scarcity. [ABSTRACT FROM AUTHOR]

In this study, the catalytic (co‐)pyrolysis of low‐density polyethylene (LDPE) and polyethylene terephthalate (PET) with HZSM‐5 and HY zeolite catalysts was conducted in a micro‐pyrolysis reactor coupled to a two‐dimensional gas chromatography system. Pyrolysis operating conditions, such as the pyrolysis temperature, the catalyst to feedstock (CF) ratio, and the LDPE:PET ratio, were varied. It was found that for the co‐pyrolysis of LDPE and PET, HZSM‐5 led to higher yields of C2‐C4 olefins and monoaromatic products. Lower CF ratios increased the yield of C2‐C4 olefins for LDPE pyrolysis, but decreased benzene yield for PET pyrolysis, concomitant with an increased yield in benzoic acid. A lower temperature of 400°C which was sufficient for the pyrolysis of LDPE, led to incomplete conversion of PET. Surface response diagrams were used to visualize the impact of the various pyrolysis operating conditions on the yield of C2‐C4 olefins and BTEX, which serve as target products for the circular economy. [ABSTRACT FROM AUTHOR]

Thailand experiences plastic waste and microplastic contamination (MPs) caused by waste disposal and leachate treatment systems. MPs often escaped from the leachate treatment. This research collected leachate and sludge samples from the leachate treatment system. This research aimed to determine the amount and characteristics of MPs and assess the effectiveness of microplastics in the leachate treatment system. The research also aimed to determine the amount of heavy metals deposited on microplastics and assess the exposure to heavy metals from the soil surrounding the leachate utilization. The microplastic samples were analyzed using a Fourier Transform Infrared Spectrometer (FTIR) to determine the composition and the type of plastic. The heavy metals on microplastics and in the open dumpsite soil were analyzed using Inductively Coupled Plasma Optical Emission (ICPOES). The study found that the efficiency of removing microplastics in the leachate treatment system was 77.55%. The microplastic content in all leachate sampling locations was 105 ± 11 pieces/l, and microplastics were found at a concentration of 65 ± 3 pieces/kg in the sludge. The detected size of microplastics ranged from 20 to 10 micrometers and fragment shapes were the most common. The composition of the most transparent microplastics was examined, with polyethylene found to be the most prevalent at 30.55%, followed by Polyester at 17.77%. Zinc was the most common heavy metal found, while Cadmium was not detected in either the wastewater or sludge samples on microplastics. Most MPs removed from the leachate accumulate in the sludge, which may pose a risk to the environment. Therefore, a way to deal with the sludge is needed to reduce the contamination of MPs. [ABSTRACT FROM AUTHOR]

Multilayer plastic (MP) commonly used in food and beverage packaging is difficult to recycle due to its layered structure, resulting in its accumulation over time; the consequent environmental harm is further exacerbated by its short lifespan. This study investigates recycled low-value MP as a modifier for polymer-modified bitumen (PMB). However, the difference in polarity between MP and PMB mixtures is a challenge, resulting in their poor compatibility and reduced mechanical properties. To overcome this, low-value MP was treated with atmospheric cold plasma and thermal oxidation to enhance its compatibility with PMB. The results indicate that plasma and thermal treatments increase the hydrophilicity of low-value MP through the formation of low-molecular-weight oxidized molecules containing hydrophilic hydroxyl (-OH) and carbonyl (C = O) groups that act as an intermediary boundary layer between the low-value MP and asphaltene-rich bitumen. Further, the optimal oxidation conditions for MP are revealed as 60 s of plasma treatment followed by heating at 150 °C for 60 min. Mixtures of PMB and optimally oxidized MP have optimal compositions of 1 wt.%, with ductility and penetration values of 87.7 cm and 57.4 mm, respectively. [ABSTRACT FROM AUTHOR]

This study applies multicriteria mathematical modeling to optimize municipal solid waste (MSW) management across a three bottom-line (BL) framework: environmental, social and economic. The interrelationships and the ripple secondary impacts among the three BLs are examined systematically using an augmented simplex lattice mixture (ASLM) method. Detailed waste and waste treatments, including pyrolysis (PY), anaerobic digestion (AD), animal feed (AF), composting (CP), recycling (RE), incineration (INC) and landfilling (LF), are constructed based on waste stream fractions and treatment allowable limits. The environmental BL is assessed using life cycle assessment (LCA). The economic BL is determined by calculating the per ton capital recovery with return, and the social bottom line is assessed using the analytic hierarchy process (AHP). The three bottom lines are optimized through a mathematical model using CPLEX solver. The results indicate that CP abates 973 kgCO2eq/t compared to 61.8 kgCO2eq/t from AD and 28.3 kgCO2eq/t from AF. CP generates $23.5/t despite its low social desirability. Plastic waste PY credits ethylene by 364 kg/t, however, it costs $226.7/t despite the subtraction of credited energy and recovered byproducts. Metal RE carbon and water footprints are −236 kgCO2eq/t and 268 m3/t, respectively. AF is the second-best economic scenario after metal RE as it generates up to $122.6/t in profit. AF production scores are second highest within the social BL after plastic PY; however, the supporting legislation sub-indicator is low. The ASLM support policy that assigns 66% to the environmental BL and 16.7% to the economic and social BL to achieve carbon neutrality within the MSW sector. [ABSTRACT FROM AUTHOR]

Plastics are omnipresent in our everyday life, and accumulation of post‐consumer plastic waste in our environment represents a major societal challenge. Hence, methods for plastic waste recycling are in high demand for a future circular economy. Specifically, the degradation of post‐consumer polymers towards value‐added small molecules constitutes a sustainable strategy for a carbon circular economy. Despite of recent advances, chemical polymer degradation continues to be largely limited to chemical redox agents or low energy efficiency in photochemical processes. We herein report a powerful iron‐catalyzed degradation of high molecular weight polystyrenes through electrochemistry to efficiently deliver monomeric benzoyl products. The robustness of the ferraelectrocatalysis was mirrored by the degradation of various real‐life post‐consumer plastics, also on gram scale. The cathodic half reaction was largely represented by the hydrogen evolution reaction (HER). The scalable electro‐polymer degradation could be solely fueled by solar energy through a commercially available solar panel, indicating an outstanding potential for a decentralized green hydrogen economy. [ABSTRACT FROM AUTHOR]

Wicked problems pose both immediate and existential threats. Within this article we explore the underlying nature of wicked problems, including the social traps embedded in them. We deconstruct the ecosystem surrounding single‐use plastics to make key points regarding controversies and conflicting interests surrounding wicked problems. We propose that wicked problems may be reframed by unpacking the relationships between individuals and collectives and how social traps are understood in terms of time horizon, ownership, responsibility, and involvement. We argue that resolutions to social traps are paramount to resolving wicked problems in the case of single‐use plastics and to wicked problems more generally. We draw from marketing, psychology, public policy, and consumer research literature to suggest specific ways marketing can mitigate or perhaps eliminate the insidious dynamic of social traps and wicked problems, and in turn affect positive outcomes to enhance the short‐term and long‐term well‐being for many consumers and stakeholders. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) is a widely used plastic that significantly contributes to environmental pollution, and its biodegradation remains challenging. This study investigates the dynamics of bacterial communities in consortia enriched with LDPE as the sole carbon source. The potential for microbial diversity to adapt to polluted environments underscores its role in bioremediation. Community analysis identified Actinobacteria and Proteobacteria as key contributors to LDPE degradation, with dominant genera including Mycobacterium, Cupriavidus, Gordonia, Ochrobactrum, Nocardia, Agromyces, Amycolatopsis, and Cellulosimicrobium. The biodegradation of untreated and pretreated LDPE films was also examined, revealing that UV pretreatment significantly enhances degradation, with weight losses of 2.22–5.17% after 120 days. In contrast, sunlight and thermal treatments resulted in lower weight losses of 1.67–4.56% and 1.42–3.22%, respectively, while untreated LDPE showed only 1.32–2.80% weight loss. These findings underscore the importance of UV pretreatment in facilitating plastic biodegradation. Furthermore, potential LDPE-degrading Actinobacteria and Proteobacteria were isolated, identified as key players in the communities and co-occurrence networks, suggesting promising candidates for developing sustainable plastic waste management solutions. Moreover, this study is the first to reveal the potential LDPE degradation abilities of several genera, including Mesorhizobium, Agromyces, Amycolatopsis, Olivibacter, Aquamicrobium, Pseudaminobacter, and others. [ABSTRACT FROM AUTHOR]

Early Day Record The extensive use of plastics, valued for their lightweight, durability, and cost‐effectiveness, has led to severe environmental pollution, with 72% of plastic waste ending up in landfills or natural habitats. Traditional methods for plastic decomposition, including both mechanical and chemical approaches, often face challenges such as incomplete degradation and stability concerns. The innovative concept of mechanical gating presents a promising solution by incorporating mechanophores into polymer structures, enabling controlled degradation. Recent advancements have focused on utilizing mechanophores, such as cyclobutane, as "door locks" to regulate the degradation process. This perspective highlights recent progress in this field, demonstrating the potential of mechanophore‐based strategies for achieving on‐demand polymer degradation. It addresses the limitations of conventional recycling methods and explores how this approach can balance polymer stability with environmental degradability, paving the way for more sustainable plastic management solutions. [ABSTRACT FROM AUTHOR]

Increasing of plastic waste threatening ecosystems globally, this experimental work investigates recycled plastics as sustainable aggregate replacements in pervious concrete. Pervious concrete allows water passage but has installation/maintenance difficulty due to high weight. This research addresses the lack of eco-friendly lightweight pervious solutions by assessing physical and mechanical performance of mixes with 100% recycled plastic and traditional aggregate percentages. Density reduced 12% using a 100% plastic aggregate mix, achieving 1358 kg/m3 with compressive strength of 3.92 MPa, adequate for non-structural applications. A 7.8% decrease in water absorption versus conventional pervious concrete signifies retained porosity and permeability despite the plastic aggregates. Though early material limitations increase costs over 199.32%, recycled plastics show viability as effective, sustainable substitutes for natural aggregates in lightweight pervious concrete. With further availability and affordability improvements, these recyclable mixes can enable significantly greener construction practices. Findings provide key insights on balancing structural requirements, eco-friendliness and water infiltration capacity in plastic-based lightweight pervious concrete for broader adoption. The research examines the mechanical and durability characteristics of Light-Weight Pervious Concrete (LWPC) composed entirely of plastic aggregate. It also investigates the economic viability and potential for sustainable urban applications. The cost assessment reveals long-term environmental advantages, even though the initial expenses are higher. Additionally, the study considers an eco-friendly approach that combines plant growth with pervious concrete to promote greater sustainability. [ABSTRACT FROM AUTHOR]

Plastic debris pollution transported by river systems to lakes and oceans has emerged as a significant environmental concern with adverse impacts on ecosystems, food webs, and human health. Remote sensing presents a cost-effective approach to bolster interception and removal efforts. However, unlike marine environments, the optical properties of plastic debris in fresh waters remain poorly understood. This study aims to address this gap by providing an open-access hyperspectral reflectance database of floating weathered and virgin plastic debris found in river systems under controlled laboratory experiments. Utilizing natural waters from the Mississippi River, the database was assembled using a remote sensing data acquisition system deployed over a hydraulic flume operating under subcritical flow conditions and varying suspended sediment concentrations. The measurements encompass hyperspectral diffused light reflectance from ultraviolet (UV, 350 nm) to shortwave infrared (SWIR, 2500 nm) wavelengths. The database archived in Network Common Data Form (NetCDF) and Comma-separated values (CSV), offers valuable insights for better understanding key spectral signatures indicative of floating plastic debris, with different fractional abundance, in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Recycling of real waste plastics with diverse composition is extremely difficult. Herein, an eco‐friendly and easy‐to‐operate strategy is demonstrated to facilitate the recycling of plastic composites and mixtures by using only water. An aqu‐thermoplastic bioplastic (CPp‐TA) is constructed with switchable water solubility and excellent thermoplastic property from natural cellulose. CPp‐TA consisted of the cellulose main chain (C) and two functional groups, internal‐plasticizing group (Pp) and switchable group (TA). It not only has outstanding thermo‐plastic formability, water resistance, and mechanical property to satisfy the daily needs, but also can be easily recycled with water by switching to the water‐soluble state. CPp‐TA can processed into various high‐performance plastic parts, fibers, heat‐sealing packaging, transparent cups, paper‐plastic composites, and aluminum‐plastic composites by conventional thermoplastic processing methods. The obtained CPp‐TA/Al/paper composite exhibits better barrier performance than the famous Tetra Pak with a complex recycling process, and can be easily separated into CPp‐TA, Al foil, and paper by using basic aqueous solution to trigger the water solubility of CPp‐TA. Similarly, CPp‐TA can be effectively separated from plastic mixtures. The recovery yield achieves to 100%. The revolutionary aqu‐thermoplastic materials and water‐recycling strategy markedly reduce the recycling difficulty of intricate plastics and promote the sustainable development. [ABSTRACT FROM AUTHOR]

The widespread availability of banana peels makes them an excellent resource for bio-fillers in developing environmentally conscious and biodegradable composites, serving as substitutes for plastic and synthetic waste. This study focuses on using banana peel waste as a bio-filler to produce lighter and cheaper materials. The extracted banana peels were subjected to alkali treatment to improve interfacial interaction, and their crystalline performance, functional categories, and morphological studies were examined using XRD, FTIR, and SEM techniques. Composite samples were fabricated with varying bio-filler ratios (0.0, 2.5, 5.0, 7.5, and 10%) to examine their thermo-mechanical and tribological attributes. The inclusion of banana peel in the epoxy matrix at up to 5% significantly enhanced mechanical performance, while 7.5% composites demonstrated higher thermal endurance with a degradation temperature of 395 °C and reduced water retention. Frictional wear of the specimens was assessed by varying sliding speeds under different loads, with the highest coefficient of friction and temperature observed under a 30 N force for BPC-10.0 specimens. This research innovatively uses banana peel powder (approx. 65 µm) to create polymeric composites, addressing the need for sustainable materials with higher specific modulus and strength compared to conventional substances. The study uniquely evaluates the physical, mechanical, structural, and tribological efficiency of raw and processed banana peel particles, with chemical modifications improving crystallinity and interfacial bonding. This comprehensive approach provides vital insights for developing sustainable alternatives to reduce plastic usage. [ABSTRACT FROM AUTHOR]

Introduction and Purpose: Microplastics, ubiquitous environmental contaminants, are increasingly recognized for their potential to impact human health. This review aims to consolidate existing knowledge on the pathways through which microplastics interact with biological systems and to elucidate their health implications. State of Knowledge: Microplastics are pervasive in various environments, from aquatic to terrestrial ecosystems, and they eventually enter the human body via ingestion, inhalation, or dermal absorption. Studies have suggested that microplastics carry toxic substances, such as heavy metals and organic pollutants, which are known endocrine disruptors and carcinogens. Additionally, the physical presence of microplastics has been linked to inflammation and other negative health outcomes. Research in this field is complex and interdisciplinary, involving toxicology, environmental science, and public health disciplines. Summary: The presence of microplastics in the human body is concerning, and there is a clear need for further research to understand the extent of health risks associated with chronic exposure. Public health strategies should include both reducing microplastic pollution and strengthening regulations on plastic waste. Meanwhile, medical professionals should consider the potential for microplastic exposure when diagnosing and treating chronic conditions. Future research should aim to clarify the mechanisms of toxicity and establish safe levels of exposure, with a multidisciplinary approach being essential for comprehensive understanding and effective intervention. [ABSTRACT FROM AUTHOR]

The purpose of this study is to improve the performance of polyvinyl chloride (PVC) ultrafiltration membrane with graphene oxide (GO) that was synthesized from the pyrolysis of polypropylene (PP) bottles. The amount of GO loading in the membrane structure was 0.05, 0.15, and 0.25 wt%. x‐ray diffractometer, FTIR, scanning electron microscopy (SEM), contact angle (CA), water content, porosity, mechanical strength were used to characterize the synthesized membranes. Cross‐sectional SEM results of membranes indicated that the modification of the membrane caused the formation of finger‐like pores in the bottom part and also these holes increased the dye rejection efficiency in the membranes of (18 wt% PVC/2 wt% PVP/0.15 wt% GO) and (14 wt% PVC/2 wt% PVP/0.25 wt% GO). The CA of the synthesized membranes were decreased from 70 in (18 wt% PVC/2 wt% PVP) to 62 in (14 wt% PVC/2 wt% PVP/0.15 wt% GO), which indicates the increase in hydrophilicity of these membranes. The results showed that the best performance is related to the membranes (18 wt% PVC/2 wt% PVP/0.15 wt% GO) and (14 wt% PVC/2 wt% PVP/0.25 wt% GO) with a rejection efficiency of 92% and 83% for 100 ppm methyl blue. [ABSTRACT FROM AUTHOR]

The efficient utilization of organic solid waste resources can help reducing the consumption of conventional fossil fuels, mitigating environmental pollution, and achieving green sustainable development. Due to its dual nature of being both a resource and a source of pollution, it is crucial to implement suitable recycling technologies throughout the recycling and upgrading processes for plastics and biomass, which are organic solid wastes with complex mixture of components. The conventional pyrolysis and hydropyrolysis were summarized for recycling plastics and biomass into high‐value fuels, chemicals, and materials. To enhance reaction efficiency and improve product selectivity, microwave‐assisted pyrolysis was introduced to the upgrading of plastics and biomass through efficient energy supply especially with the aid of catalysts and microwave absorbers. This review provides a detail summary of microwave‐assisted pyrolysis for plastics and biomass from the technical, applied, and mechanistic perspectives. Based on the recent technological advances, the future directions for the development of microwave‐assisted pyrolysis technologies are predicted. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate harmful compound levels in Shikaripara stone mines’ cultivated land, which is renowned for stone quarrying in Jharkhand, India. Sixteen samples were collected from the mines in Dumka district, each at varying distances from the others. The soil samples contain Pb, As, Zn, Mn, Cd, Cu, Hg, and Fe. An Inductively Coupled Plasma-Mass Spectrometer was used to determine the total concentrations of the metals (ICPMS). Calculations of the Enrichment Factor (EF), Geo-accumulation Index (I geo), Contamination Factors (CF), Pollution Load Index (PLI), Nemerow Index, and ecological Risk Index (RI) PLI, RI, and Nemerow Index values, considering various toxic substances’ effects on soils overall, revealed significant metal contamination in 50 % of the sampled areas. Agricultural soils exhibited significant contamination with Cu, As, and Zn as a result of nearby copper mining activities. Results advocate regular soil examination and efficient management to reduce metal pollution. Compared to other areas, contamination levels in the study region are relatively lower, emphasizing the need for continued monitoring and management. The report delves into ecological services, assessing the impacts of plastic particles and heavy metals. It sets the stage for further research on the combined effects of these substances and plastic debris on biodiversity. [ABSTRACT FROM AUTHOR]

The pressing need to mitigate climate change and drastically reduce environmental pollution and loss of biodiversity has precipitated a so-called energy transition aimed at the decarbonization of energy and defossilization of the chemical industry. The goal is a carbon-neutral (net-zero) society driven by sustainable energy and a circular bio-based economy relying on renewable biomass as the raw material. It will involve the use of green carbon, defined as carbon derived from terrestrial or aquatic biomass or organic waste, including carbon dioxide and methane emissions. It will also necessitate the accompanying use of green hydrogen that is generated by electrolysis of water using a sustainable source of energy, e.g. solar, wind or nuclear. Ninety per cent of the industrial chemicals produced in oil refineries are industrial monomers that constitute the precursors of a large variety of polymers, many of which are plastics. Primary examples of the latter are polyolefins such as polyethylene, polypropylene, polyvinyl chloride and polystyrene. Polyolefins are extremely difficult to recycle back to the olefin monomers and discarded polyolefin plastics generally end up as the plastic waste that is responsible for the degradation of our natural habitat. By contrast, waste biomass, such as the lignocellulose contained in forestry residues and agricultural waste, constitutes a renewable feedstock for the sustainable production of industrial monomers and the corresponding polymers. The latter could be the same polyolefins that are currently produced in oil refineries but a more attractive long-term alternative is to produce polyesters and polyamides that can be recycled back to the original monomers: a paradigm shift to a truly bio-based circular economy on the road to a net-zero chemical industry. This article is part of the discussion meeting issue 'Green carbon for the chemical industry of the future'. [ABSTRACT FROM AUTHOR]

The issue of non-degradable petroleum-based plastic waste is a global challenge that requires urgent attention due to its harmful impact on humans and the environment. Biomass-based materials have garnered significant attention to address this challenge in recent times. Lignin, with its abundance, low price, and rich aromatic groups, is not only essential biomass but also a crucial material that can be utilized to produce biodegradable polymers. This review paper provides comprehensive knowledge of the synthesis and applications related to lignin, polyester, and lignin–polyester copolymers with a specific focus on organic polymer synthesis techniques and diverse applications. Beginning with lignin, the review explores various extraction methods from raw biomass resources aimed at enhancing its compatibility with polyester matrices. Next, we discuss lignin chemical modification methods that alter its chemical structure and properties, ultimately enhancing its integration with polyesters. Subsequently, the synthesis of polyester is examined, encompassing condensation polymerizations and ring-opening polymerizations. These methods are evaluated for their scalability and capability in producing tailored polymer chains suitable for copolymerization with lignin. The copolymerization strategies involving lignin and polyester are explored in detail, including graft-onto and graft-from approaches. Each method is discussed for its ability to control copolymer composition and properties, which are crucial for achieving desired material characteristics. In terms of applications, the review highlights the wide-ranging utility of lignin–polyester copolymers across industries such as packaging, construction, and separation. These polymers offer improved biodegradability, thermal stability, and mechanical strength compared to conventional polyesters, making them perfect candidates for novel sustainable materials. Overall, this review provides valuable insights into the synthesis methods and applications of lignin, polyester, and lignin–polyester copolymers offering a comprehensive overview of their potential for addressing environmental concerns and expanding the scope of lignin-derived materials in various industrial applications. [ABSTRACT FROM AUTHOR]

Chemical recycling of plastics has gathered momentum to manage plastic waste and replace fossil-based feedstocks. However, chemical recycling of complex polymers, such as polyurethane (PU) rigid foam, can yield a variety of intermediates. But which intermediates reduce environmental impacts the most when produced from PU is currently unclear. In this work, we assess the potential of chemical recycling of PU rigid foam waste to reduce environmental impacts compared to state-of-the-art treatment options, such as incineration and landfilling. For this purpose, we extend the environmental potential methodology to account for any possible recycling product. We then calculate the environmental potential for six ideal closed-loop recycling options and one experimentally demonstrated recycling option based on a patent. All analyzed chemical recycling options for PU rigid foam to various intermediates are shown to offer a substantial environmental potential to reduce multiple environmental impacts. The best performing option recovers both polyol and isocyanate and can decrease climate change impacts by 3.8–5.6 kgCO2eq. per kg PU treated. However, PU rigid foam recycling to low-value intermediates, such as benzene, does not seem promising due to burden shifting actually increasing half of the analyzed environmental impacts. We further determine the minimal conversion rates required to reduce environmental impacts by chemical recycling of PU rigid foam. Our environmental potential analysis assists the decision-making process for product prioritization in recycling and identifies (side-)products whose recovery is worth investigating from an environmental perspective. [ABSTRACT FROM AUTHOR]

The recycling and upcycling of polyethylene terephthalate (PET), the most widely used polyester plastic globally, has attracted growing attention concerning its disposal as non‐degradable waste in the natural environment. Transforming end‐of‐life PET into (bio)degradable polyester offers a novel approach to managing its waste. In this study, we introduce a simple process capable of converting waste PET into degradable polyester, polyethylene terephthalate‐polyethylene‐1,4‐cyclohexanedicarboxylate (PET‐PECHD), by partly hydrogenating the aromatic rings (x) into aliphatic ones (y). The polyesters with variable x/y compositions ranging from 100/0 to 0/100 can be achieved, and the molecular weight (Mw) can be maintained when x/y >87/13 due to the nonobvious depolymerization. Pronounced depolymerization would occur with deeper hydrogenation, which generates a blend of PET‐PECHD and polyethylene‐1,4‐cyclohexanedicarboxylate (PECHD) with lower Mw, and finally a single‐type polymer PECHD. The PET‐PECHD demonstrates comparable thermal stability and mechanical strength compared to PET, along with superior extensibility, barrier properties, and (bio)degradability in acidic, alkaline solutions, and moist soil. This research highlights the potential for cost‐effective, large‐scale production of degradable polyester from real‐life plastic waste. [ABSTRACT FROM AUTHOR]

Plastic waste and wastewater are indeed significant environmental issues that have wide‐ranging impacts on ecosystems, human health, and the economy. This study outlines the synthesis of biodegradable polyvinyl alcohol (PVA)–starch polymeric films incorporating multiwalled carbon nanotubes (MWCNTs) derived from plastic waste and unzipped carbon nanotubes oxides (UMCNOs) as co‐filled nanomaterials. These films were formulated based on data generated using a mixture design method in Design Expert 13 software, resulting in the synthesis of 19 films utilizing five types of PVA–starch polymer solutions (Types A–E). The synthesized films underwent characterization to study their surface morphology via scanning electron microscope and Fourier transform infrared spectroscopy analysis. Subsequently, the films were individually subjected to vacuum filtration, through which cationic dyes such as methylene blue (MB) and anionic dye Congo red (CR) were passed in batches. The highest removal efficiency of 96.43% for MB dye was achieved, accompanied by an exceptionally high flux of 3146.78 LMH. Similarly, the maximum removal of 88.08% for CR was observed with a flux of 1512.66 LMH. The renewable active sites mechanism resulted in increased dye removal with every cycle. Results indicated efficient reusability, particularly when washed with ethanol–water solution. [ABSTRACT FROM AUTHOR]

The development of the online meal-delivery industry is a double-edged sword, with potential to both hamper and drive progress towards achievement of the Sustainable Development Goals (SDGs). Yet most studies examining this industry have been conducted from the narrow perspective of specific academic fields, focusing on single issues or on individual cases. In this paper, by drawing upon the thematic foci of the SDGs as an analytical framework, we conducted a systematic and objective review to assess consequences of the online meal-delivery's development for sustainable development. After selecting and reviewing 128 peer-reviewed articles identified on Web of Science, we systematically coded their contents, and examined key trends along with knowledge gaps. The review shows that direct consequences for the SDGs—for instance, human health, plastic waste, carbon emissions, and labor conditions—have been thoroughly discussed. Conversely, we found a lack of attention to other indirect but important consequences, including impacts on poverty, hunger, education, and gender equality, which are yet to be thoroughly investigated. Particularly, our findings point to a need for more knowledge on how the industry is impacting food access in light of the "digital divide" between IT-literate consumers and those possessing less familiarity with digital technologies, how employment opportunities contribute to poverty alleviation or exacerbation of class gaps, and how the meal-delivery industry can contribute to achieving zero hunger by increasing food access to vulnerable populations. Our findings generate important insights to guide the formulation of more targeted countermeasures to address issues that risk hindering achievement of sustainable development. [ABSTRACT FROM AUTHOR]

With the escalating demand and utilization of plastics, considerable attention has been given to controlling plastic pollution. Among these methodologies, photocatalytic upcycling of plastic has emerged as a promising method for plastic management due to its energy‐saving and eco‐friendly properties. In the past several years, great efforts have been devoted to the photocatalytic conversion of a variety of commercial plastic types. These encouraging endeavors foreshadow the continued progression and application in this field. In this review, recent advancements in the photocatalytic upcycling of plastics are reviewed. The fundamentals and principles of photocatalytic deconstruction of plastics are first introduced. Then, we summarize the works on the reforming of different types of plastic, including polyolefins, polyesters, and other types. Finally, some challenges and possible solutions are provided for the development of photocatalytic upcycling of plastics. [ABSTRACT FROM AUTHOR]

The presence of plastics in the automotive industry is increasingly significant due to their lightweight nature, which contributes to reducing fuel consumption and CO2 emissions while improving versatility and mechanical properties. Polypropylene (PP) and other polyolefins are among the most commonly used materials, especially for components such as bumpers. The use of composite materials, i.e., a combination of different polymers, improves the properties through synergistic effects, thereby also improving the performance of the final product. In the automotive industry, PP reinforced with 20% talc or CaCO3 is commonly used. The mechanical recycling of polypropylene bumpers is the most common type of recycling. However, challenges arise during this process, such as the presence of impurities like paint, chemical contaminants from previous use, and polymeric impurities from different polymers mixed into the polymer matrix, among others. Paint affects both the aesthetic quality and the mechanical and intrinsic properties of the recycled material. This review aims to analyze the main methods reported in the literature, focusing on those with low environmental impact. Furthermore, these methods are classified according to their capacity, effectiveness, substrate damage, environmental hazards, and economic feasibility. It also aims to offer a comprehensive overview of the mechanical recycling of plastic waste in the automotive industry. [ABSTRACT FROM AUTHOR]

Development of multi-component blends to prepare high-performance polymer materials is still challenging, and is a key technology for mechanical recycling of waste plastics. However, a multi-phase compatibilizer is prerequisite to create high-performance multi-component blends. In this study, POE-g-(MAH-co-St) and SEBS-g-(MAH-co-St) compatibilizers are prepared via melt-grafting of maleic anhydride (MAH) and styrene (St) dual monomers to polyolefin elastomer (POE) and poly [styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS), respectively. Subsequently, these compatibilizers are utilized to compatibilize the PA6/PP/ABS/SEBS quaternary blends through melt-blending. When POE-g-(MAH-co-St) and SEBS-g-(MAH-co-St) are added, respectively, both can promote the distribution of the dispersed phases, significantly reducing the dispersed phase size. When adding 10 wt% POE-g-(MAH-co-St) and 10 wt% SEBS-g-(MAH-co-St) together, compared to the non-compatibilized blend, the fracture strength, fracture elongation, and impact strength surprisingly increased by 106%, 593%, and 823%, respectively. It can be attributed to the hierarchical interfacial interactions which facilitate gradual energy dissipation from weak to strong interfaces, resulting in the improvement of mechanical properties. The synergistic effect of the enhanced phase interfacial interactions and toughening effect of elastomer compatibilizer achieved simultaneous growth in strength and toughness. [ABSTRACT FROM AUTHOR]

This study investigates the feasibility of incorporating shredded polyethylene terephthalate (PET) post-consumer plastic waste as a partial replacement for coarse aggregates in unreinforced concrete such as masonry blocks. Standard concrete blocks were produced with varying PET content (0%, 5%, 25%, 35%, 50%) and tested for workability, air content, density, compressive strength, flexural strength, and thermal conductivity. Results indicated that replacing up to 25% of traditional aggregates with PET maintains adequate compressive strength for non-load-bearing applications and enhances thermal insulation by reducing the thermal conductivity from 0.7 W/m·°K to 0.27 W/m·°K at 25% replacement level, representing a significant improvement of approximately 61%. Higher PET content (35–50%) resulted in reduced structural integrity but improved insulation, suggesting its suitability for non-structural applications. This research highlights the potential of using PET plastic waste in unreinforced concrete, promoting sustainable construction practices by reducing plastic waste and conserving natural resources. [ABSTRACT FROM AUTHOR]

Arbitrary disposal of plastic waste into landfills and oceans can disturb the ecological system and even challenge human survival. Centralized plastic recycling process only works for selected types of plastics (e.g., polyethylene) with limited contribution (<10%), because of high infrastructure requirement. Comparatively, photoreforming of plastic waste for commodity and fuels production is much more facile and decentralizable, and thus holds great potential to mitigate the plastic waste challenge. To this end, a fully solar powered photoelectrochemical system is developed to selectively upgrade polyimide waste (often appears in electronic waste) into valuable commodity chemicals, including succinic acid, acetic acid, and formic acid, and cogenerating green hydrogen fuels. It is also demonstrated that one of the key monomer, pyromellitic acid, and the precious metals (in electronic waste) can be fully recycled. This proof‐of‐concept demonstration provides a new viewpoint for designing decentralized photoelectrochemical system for simultaneous plastic waste upcycling and renewable fuel synthesis, critical for a sustainable plastic economy. Selective cleavage of benzene ring also opens a green route for other benzene ring‐containing waste upgrading. [ABSTRACT FROM AUTHOR]

Anaerobic digestion and composting of biowastes are vital pathways to recycle carbon and nutrients for agriculture. However, plastic contamination of soil amendments and fertilizers made from biowastes is a relevant source of (micro‐) plastics in (agricultural) ecosystems. To avoid this contamination, plastic containing biowastes could be pyrolyzed to eliminate the plastic, recycle most of the nutrients, and create carbon sinks when the resulting biochar is applied to soil. Literature suggests plastic elimination mainly by devolatilization at co‐pyrolysis temperatures of > 520°C. However, it is uncertain if the presence of plastic during biomass pyrolysis induces the formation of organic contaminants or has any other adverse effects on biochar properties. Here, we produced biochar from wood residues (WR) obtained from sieving of biowaste derived digestate. The plastic content was artificially enriched to 10%, and this mixture was pyrolyzed at 450°C and 600°C. Beech wood (BW) chips and the purified, that is, (macro‐) plastic‐free WR served as controls. All biochars produced were below limit values of the European Biochar Certificate (EBC) regarding trace element content and organic contaminants. Under study conditions, pyrolysis of biowaste, even when contaminated with plastic, can produce a biochar suitable for agricultural use. However, thermogravimetric and nuclear magnetic resonance spectroscopic analysis of the WR + 10% plastics biochar suggested the presence of plastic residues at pyrolysis temperatures of 450°C. More research is needed to define minimum requirements for the pyrolysis of plastic containing biowaste and to cope with the automated identification and determination of plastic types in biowaste at large scales. [ABSTRACT FROM AUTHOR]

Biochar is the product of intentional pyrolysis of organic feedstocks. It is made under controlled conditions in order to achieve desired physico‐chemical characteristics. These characteristics ultimately affect biochar properties as a soil amendment. When biochar is used for carbon storage, an important property is its persistence in soil, often described by the proportion of biochar carbon remaining in soil after a 100 years (Fperm$$ {\mathrm{F}}_{\mathrm{perm}} $$). We analyzed published data on 1230 biochars to re‐evaluate the effect of pyrolysis parameters on biochar characteristics and the possibility to predict Fperm$$ {\mathrm{F}}_{\mathrm{perm}} $$ from the maximum temperature reached during pyrolysis (HTT). We showed that biochar ash and nitrogen (N) contents were mostly affected by feedstock type. The oxygen to carbon (O:C) and hydrogen to carbon (H:C) ratios were mostly affected by the extent of pyrolysis (a combination of HTT and pyrolysis duration), except for non (ligno)cellulosic feedstocks (plastic waste, sewage sludge). The volatile matter (VM) content was affected by both feedstock type and the extent of pyrolysis. We demonstrated that HTT is the main driver of H:C ‐‐ an indicator of persistence ‐‐ but that it is not measured accurately enough to precisely predict H:C, let alone persistence. We examined the equations to estimate Fperm$$ {\mathrm{F}}_{\mathrm{perm}} $$ available in the literature and showed that Fperm$$ {\mathrm{F}}_{\mathrm{perm}} $$ calculated from HTT presented little agreement with Fperm$$ {\mathrm{F}}_{\mathrm{perm}} $$ calculated from H:C. The sign and magnitude of the bias depended on the equation used to calculate Fperm$$ {\mathrm{F}}_{\mathrm{perm}} $$ and the dispersion was usually large. This could lead to improper compensation of carbon emissions and wrong reporting of carbon sinks in national carbon accounting schemes. We recommend not to use HTT as a predictor for persistence and stress the importance to rapidly develop more accurate proxies of biochar C persistence in soil. [ABSTRACT FROM AUTHOR]

Increasing global consumption of low-density polyethylene leads to more polymeric waste and challenges solid waste management. Therefore, the process of recycling or mixing recycled low-density polyethylene (RLDPE) with the same virgin low-density polyethylene (VLDPE) and enhancing the properties of this blend by adding different amounts of bioplastic such as Octanoate starch (OCST) is a good contribution to getting rid of plastic waste and obtaining new materials. This paper mixed the 20, 30 and 50 wt.% from RLDPE with VLDPE to determine the homogeneous blend. Also, 30, 40, and 50 wt. % from OCST were blended with homogeneous as a 20:80 RLDPE: VLDPE to obtain a new hybrid blend containing bioplastic. The scanning electron microscope (SEM) results showed the high surface roughness of the film RLDPE: VLDPE after adding the OCST. The tensile strength, elastic modulus, and hardness of the 20:80 RLDPE: VLDPE blend were 13.0 ± 1.467 MPa, 0.08 ± 0.016 MPa, and 42.3 ± 2.32 Shore A, while the tensile strength, elastic modulus, and hardness of the 12:48:40 RLDPE: VLDPE: OCST were 14.3 ± 1.626 MPa, 0.1 ± 0.032 MPa, and 50.1 ± 2.78 Shore A respectively. On the other hand, the Fourier-Transform Infrared (FTIR) indicated that the strong bands at 1746 cm−1, 2856 cm−1, and 2927 cm−1 indicated stretching deformation of the ester carbonyl group and the methyl and methylene groups of OCST with blend polymers, respectively. The thermal properties as melting point, heat energy consumption, and heat flow difference increased from 122.52 to 123.73°C, −389.41 to −144.43 (mJ), and −77.88 to −28.89 (J/g) when the OCST content increased from 20:80 RLDPE: VLDPE to 12:48:40 RLDPE: VLDPE: OCST. Thermal decomposition led to the formation of functional groups such as hydroxyl and carbonyl on LDPE baskets and an increase in the carbonyl index after adding OCST to the RLDPE: VLDPE blend. The best hybrid blend was 12:48:40 RLDPE: VLDPE: OCST. [ABSTRACT FROM AUTHOR]

The extensive use of non-biodegradable and petroleum derived polymers in industry exacerbates environmental problems associated with plastic waste accumulation and fossil resource depletion. The most promising solution to overcome this issue is the replacement of these polymers with biodegradable and bio-based polymers. In this paper, novel biocomposites were prepared from bio-based polyamide 5.6 (PA56) with the addition of olive stone powder (OSP) at varying weight concentrations by melt compounding method. The degradability of the prepared biocomposites is investigated through soil burial test, and assessed by reduction in their mechanical properties. The biodegradability of bio-based polyamide 5.6 is shown to be improved by addition of olive stone powder, and its effects on the properties of polymer matrix are elucidated. The Fourier transform infrared (FTIR) spectrum of the biocomposites indicate the successful incorporation of OSP into PA56 polymer matrix. After six-month soil burial test, scanning electron microscopy and FTIR show the degradation of PA56 through morphological and structural changes, respectively. Differential scanning calorimetry reveals the changes in the transition temperatures of the polymer matrix and an increase in crystallinity. Thermogravimetric analysis is used on the biocomposite to determine the fraction of its components, polymer and biofiller, and the results show that 2.67% (w/w) of the polyamide 5.6 is biodegraded at the end of the six-month soil burial. [ABSTRACT FROM AUTHOR]

With a growing global awareness of the ecological challenges posed by plastic waste, the integration of recycled materials represents a crucial step to sustainable additive manufacturing of plastic products. To assess the applicability of recycled materials in 3D printing, we extruded recycled polylactic acid (PLA) into filament and printed specimens based on the fused filament fabrication (FFF) printing technology. For comparison purposes, we selected the virgin PLA filament as a reference. With the filament extruder, we produced filaments using virgin PLA pellets, a mixture of virgin pellets and recycled PLA, as well as fully recycled PLA. The extrudability and transferability of filaments were comprehensively investigated under various extrusion temperatures and speeds. Subsequently, using extruded filaments, we printed parts of different shapes such as cubes, tensile specimens, and flexural specimens. We measured the surface roughness, dimensional deviations, and mechanical properties of the printed parts. Results demonstrated that filament extruded from virgin pellets exhibited similar quality and mechanical properties as the virgin filament. Recycled PLA required higher extrusion temperature and speed to extrude filament than virgin PLA and mixed virgin PLA and recycled PLA. The tensile and flexural strength of printed parts from fully recycled PLA were more than 15 % lower than that from virgin filament. These findings contribute valuable insights towards the continued development of environmentally conscious practices in the field of additive manufacturing. [ABSTRACT FROM AUTHOR]

Problem definition: About 30 million tons of plastic waste reaches the oceans each year, mostly from low- and middle-income coastal countries. We study novel business models of firms aiming to reduce ocean plastic pollution with a triple-bottom-line (TBL) objective—a weighted sum of profit, environmental impact, and social impact. These firms sell (a) plastic offsets and (b) segregated plastic. Methodology/results: We develop and analyze models where a firm partners with a local plastic recycling supply chain to sell (a), (b), or both via collecting and recycling ocean-bound plastic. Considering additionality (i.e., that the firm can only sell plastic offsets based on recycled plastic that is additional to the plastic recycled without the firm's presence), we solve the equilibrium outcomes by maximizing the firm's TBL objective. For the special case of a for-profit firm, we show that additionality can decrease the firm's social and environmental impacts when selling (a) only or when selling both (a) and (b). Additionality may also alter the effect of the local recycled plastic market (i.e., the number of collectors and the recycled plastic price) on the firm. We find similar insights under the TBL objective via a numerical study calibrated with real data. Managerial implications: When firms decide whether to integrate and promote additionality, they must be careful because it may not only reduce their profit but also, reduce their social and environmental impacts. Moreover, we find that selling both (a) and (b) can generate a much higher TBL objective value than selling either one alone. We also find that firms employing a TBL objective can generate much larger environmental and social impacts with a slight reduction in profits than profit-maximizing firms. Our model and results provide insights into new initiatives for tackling ocean plastic pollution. Funding: O. Baron and G. Romero are both supported by the Natural Science and Engineering Research Council of Canada. Z. Zhang is partially supported by the Fundamental Research Funds for the Central Universities of Xiamen University [Grant 20720241012]. S. X. Zhou is partially supported by the Hong Kong Research Grants Council General Research Fund [Grant CUHK-14500921], the National Natural Science Foundation of China [Grant 72394395], and the Asian Institute of Supply Chains and Logistics. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.0643. [ABSTRACT FROM AUTHOR]

This work describes a very efficient methodology for the methanolysis of polyester and polycarbonate plastic waste into a variety of valuable products using homogeneous and heterogeneous manganese compounds in the presence of KOtBu. Excellent yields are obtained using 1 mol% of the homogeneous catalysts Mn(OTf)2, Mn2(CO)10, MnBr(CO)5, and MeCpMn(CO)3 and 5 mol% of KOtBu, under mild reaction conditions. The heterogeneous manganese catalyst, manganese(II) ethyl/butyl phosphonate silica (Si‐Mn), also successfully promoted the methanolysis of polyester and polycarbonate plastic waste with excellent yields. Furthermore, this heterogeneous catalyst can be applied in at least 12 catalytic cycles with excellent yields. [ABSTRACT FROM AUTHOR]

Plastic pollutants create health crises like physical damage to tissues, upset reproductive processes, altered behaviour, oxidative stress, neurological disorders, DNA damage, gene expression, and disrupt physiological functions, as the biosphere accumulates them inadvertently through the food web. Water resources have become the generic host of plastic wastes irrespective of their particle size, resulting in widespread distribution in aquatic environments. The pre-treatment step of the traditional water treatment process can easily remove coarse-sized plastic wastes. However, the fine plastic particles, with sizes ranging from nanometres to millimetres, are indifferent to the traditional water treatment. To address the escalating problems, the upgradation of different traditional physical, chemical, and biological remediation techniques offers a promising avenue for tackling tiny plastic particles from the water environment. Further, new techniques and hybrid incorporations to the existing water treatment techniques have been explored, specifically removing tiny plastic debris. A detailed understanding of the sources, fate, and impact of plastic wastes in the environment, as well as an evaluation of the above treatment techniques and their limitations and challenges, can only show the way for their upgradation, hybridization, and development of new techniques. This review paper provides a comprehensive overview of the current knowledge and techniques for the remediation of nanoplastics and microplastics. [ABSTRACT FROM AUTHOR]

In this study, lanthanum oxide (La2O3) nanoparticles or lanthana were synthesized by the planetary ball milling method and then used as a filler for the preparation of the polypropylene (PP) based nanocomposites by solution mixing method. The PP used in the study was derived from the discarded saline bottles. The structural and the surface morphology of the synthesized lanthanum oxide nanoparticles were characterized by XRD, SEM and FTIR. The thermogravimetric analysis (TGA) study revealed that the thermal stability of the nano lanthana composites increased with the addition of the lanthanum oxide nanoparticles. The mechanical properties, such as Young's modulus and tensile strength, were also improved by the addition of the lanthanum oxide nanoparticles to the PP matrix. The composites also showed antibacterial activity against Escherichia coli bacteria. This approach not only mitigates medical plastic waste and environmental impact but also paves the way for versatile polymer nanocomposites with extensive industrial applications, especially in biomedical packaging. [ABSTRACT FROM AUTHOR]

The global issue of plastic waste accumulation is now widely acknowledged as a significant environmental challenge that affects all aspects of life, economies, and natural ecosystems worldwide. Hence, it is crucial to develop sustainable solutions to traditional disposal methods. One promising solution involves upcycling plastic waste into valuable carbon nanomaterials such as carbon nanotubes, graphene, and carbon nanofibers, among others. This critical review provides an overview of the problems associated with plastics, including their various types and properties, as well as their significant impact on the environment and the methods currently employed for waste management. Furthermore, it delves into recent advancements in upcycling plastic waste into carbon nanomaterials through four state‐of‐the‐art methods with the potential for scaling up and enabling industrial applications: thermal decomposition, flash joule heating (FJH), chemical vapor decomposition (CVD), and stepwise conversion. For each method, highly influential and seminal papers were selected, and their research approaches and observed results were thoroughly analysed. This upcycling approach transforms plastic waste into valuable resources, promoting a waste‐to‐value concept that reduces environmental impact and supports the circular economy. By creating new materials from discarded plastics, it addresses waste management challenges while generating economic value. [ABSTRACT FROM AUTHOR]

Recycled plastics value chains are being collaboratively constructed amid calls for greater responsibility of the corporates driving today's plastic waste crisis. The resulting 'responsibility fix' bolts new arrangements onto linear production processes, offering a mechanism to push linear processes towards circularity, while starting to patch up some of the social and economic injustices associated with waste-picking work within contemporary systems of capitalist production and consumption. This research draws upon semi-structured interviews to trace international collaborations within recycled plastics value chains to identify how new, low-disruption, circular business models are being built. [ABSTRACT FROM AUTHOR]

As human activities continue to increase, the production and utilisation of plastics have become pervasive, leading to a surplus of plastic waste in the environment. This has turned the terrestrial ecosystem, encompassing soil, into a significant receptacle for the growing accumulation and discharge of plastic waste. Thus, the objective of this study is to investigate the occurrence, relationships, sources and pollution levels of microplastics in urban soils from different land use activities in Cyberjaya, Malaysia. Surface soil samples were collected from land uses (i.e., vacant areas, residential areas, commercial areas, construction areas and roadways). These surface soil samples were analysed for microplastic occurrence using density separation, microscopy and spectroscopy methods. The microplastics particles were analysed for size, colour and shape. Selected microplastics particles were also analysed for its plastics polymers using Fourier‐Transform Infrared Spectroscopy. Microplastics occurrence ranged from 0.3 to 1.5 particle/kg, with the highest average occurrence in the construction area (0.69 particle/kg) and lowest in the vacant area (0.33 particle/kg). Microplastics particle size was shortest in commercial areas (586.08 μm) and longest in vacant areas (793.78 μm). There were no similarities between microplastics occurrence and particle size across these different land use activities, suggesting that the microplastics occurrence in urban soils depends on external disturbances during each land use activity. Significant correlation between microplastic particle size and temperature (r2 = 0.517) showed that each land use activity is influenced by external disturbances. The Igeo values showed that the microplastics pollution level in urban soils is classified as uncontaminated to moderately contaminated. Microplastic particles in urban soils were found in various shapes (i.e., fragments, films and fibres) and colours (i.e., transparent, grey, blue, red, green, purple, black, white and yellow) along with plastic polymer types (i.e., ABS, PET, PP, PE and PS) due to traffic volume, tyre wear, mismanaged plastic waste and degradation rate. This study highlights the need for pollution management and waste disposal to avoid urban environmental problems and adverse health effects. [ABSTRACT FROM AUTHOR]