CATALYTIC PYROLYSIS OF DISCARDED COVID-19 MASKS OVER SEPIOLITE

This research aims to develop a new strategy to valorize wasted COVID-19 masks based on pyrolysis to convert them into useful products. First, surgical and FFP2 masks were thermally pyrolyzed at temperatures of 450–550 ºC with the purpose of determining gas, liquid (oil) and solid (char) yields. At low temperatures, solid yield was high, while at high temperatures the gas product was enhanced. The highest yield of liquid was found at an operating temperature of 500 ºC in both surgical and FPP2 masks pyrolysis. The liquid product yields were 59.08% and 58.86%, respectively. Then, the volatiles generated during thermal pyrolysis of residual masks were cracked over sepiolite as catalyst at a temperature of 500 ºC. The catalytic pyrolysis increased the yield of gas product (43.89% against 39.52% for surgical masks and 50.53% against 39.41% for FFP2 masks) and decreased the viscosity of the liquid product. Finally, the effect of sepiolite regeneration and reuse in consecutive pyrolysis tests was examined. Results showed that, with the higher regeneration-reuse of sepiolite, the catalyst was degraded obtaining a liquid product with higher molecular mass. This effect was hardly noticeable in the case of FFP2 masks. © 2022 International Multidisciplinary Scientific Geoconference. All rights reserved.

Valorization of hazardous plastic wastes into value-added resources by catalytic pyrolysis-gasification: A review of techno-economic analysis

Plastic waste pollution has grown exponentially since the 1950s. This situation was exacerbated when the volume of personal protective equipment (PPE)-based plastic waste surged after the COVID-19 pandemic. Plastic waste management such as landfills and incineration have adverse effects on the environment and human health due to the leaching of hazardous chemicals and the emission of toxic gases. Modern solutions such as biodegradable plastics and green brick technology are expensive and not well developed to valorize the current accumulation of plastic waste. This has led to the emergence of thermal degradation processes, which is faster and more realistic to solve the PPE-based plastic waste buildup. Pyrolysis and gasification systems to valorize plastic waste into hydrocarbons and fuels are discussed and compared with examples respectively. Scoping review approach is employed to conduct this study. To further increase the value of the final product of plastic waste management, the integrated pyrolysis system to upcycle plastic waste to carbon nanomaterials (CNMs) and the factors affecting the production of non-condensable gases are critically reviewed. The importance of feedstock composition, catalyst type, pyrolysis operating condition (including gas condition and temperature profiles) based on various studies is discussed. The potential and limitation of an integrated pyrolysis system are assessed from kinetic analysis, economic analysis and life-cycle assessment. This review is expected to contribute to the industrial-scale development of sustainable upcycling of plastic waste and enhance the production of desirable gas components for CNM synthesis for environmental sustainability.

Optimizing plastics recycling networks

Plastic pollution is a serious sustainability issue facing the global community. Fragments of macroplastics and microplastics pollute terrestrial and aquatic ecosystems, while nanoplastics can also degrade air quality. The recent COVID-19 pandemic also exacerbated the problem. Large-scale commercial use of plastics recycling technologies is hindered by various socio-economic barriers. In particular, cross-contamination of mixed plastic streams is prevalent due to imperfect waste segregation. The concept of Plastics Recycling Networks is introduced to facilitate planning of reverse supply chains using optimization models. In this work, basic Linear Programming and Mixed-Integer Linear Programming models are developed for matching sources of waste plastic with plastic recycling plants within Plastics Recycling Networks. These models allocate streams while considering the ability of recycling plants to tolerate contaminants. Two illustrative case studies are analyzed to demonstrate the effectiveness of the models, and policy implications for mitigation of plastic pollution are discussed. These models enable planning of networks with some tolerance for contaminants in plastic waste, and can be the basis for developing new variants to handle additional real world aspects.

AS FOOD DELIVERY BUSINESS IS SKYROCKETING, SO IS OUR ENVIRONMENTAL DISASTER

This chapter discusses the high adoption of plastic bags/packages by food providers in Malaysia during pandemic that resulted in a long-time lockdown. Under the federal government act of ‘Movement Order Control' (MCO), people had no choice but to order food or purchase food ingredients via online food delivery services. Such situation made the food delivery business instantly one of the top and essential economic contributors. However, this also severely impacted our environment specifically the growing usage of plastic bag, plastic food container, and parcel packaging. While the food delivery company introduces a campaign to reduce and replace the plastic bag/packages, the awareness level is still very low. This chapter highlights the introduction of food delivery business striving in the COVID-19 pandemic, the severity of plastic usage and challenges of sustainability marketing campaign in Malaysia. © 2023 by Emerald Publishing Limited.

A review of plastic pollution and their treatment technology: A circular economy platform by thermochemical pathway

The rapid expansion of plastic manufacturing industries in last several decades has brought serious concerns over the environmental impacts of plastic wastes. Recent outbreak of Covid-19 drastically increased production, use, and disposal of plastic products. Current management strategies for wasted plastics still rely on landfill and incineration that continue to exacerbate plastic pollution and carbon emissions. Many countries have put forward multifaceted administrative efforts to reduce plastic wastes, but the annual global generation of plastic wastes is still increasing. In techno-society, researchers have been exploring more effective plastic wastes treatment technologies to alleviate environmental impacts of plastic wastes. Such efforts entailed several technical options that can potentially contribute to establishing a circular economy for plastics. Thermochemical process is a prominent example of such techniques. This review presents an overview of the issue of plastic pollution, covering topics including global plastic production, environmental impacts, and toxicity. In addition, the global administrative efforts aimed at reducing plastic pollution are discussed, as well as detection and treatment strategies to establish a circular economy in plastic management. © 2023 Elsevier B.V.

CHANGING LANDSCAPE OF PLASTIC WASTE MANAGEMENT IN INDIA

Plastic waste is one of the long-standing global issues in the recent era. Unfortunately, India is one of the countries which has been affected by the mismanagement of the use of plastics. India has recorded a substantial growth in the production of plastic and is considered a country of increased consumption of plastic. Due to the absence of an appropriate waste collection and segregation process, it has created the major issue of waste management and discarded used plastic items used for packaging application. There are various plastic waste management laws and programmes that have a cascading effect on almost every sector of business. In 2016, two years after the new union government took power in New Delhi, The Ministry of Environment, Forest and Climate Change (MoEFCC) has made some improvements in rules for the collection, segregation, processing, treatment and disposal of the waste. In the pandemic era, effective plastic waste management became more important than ever. The COVID-19 pandemic has created an increased demand for single-use plastic because of pressure on the already out-of-control global plastic waste problem. It is recorded to be large, and the magnitude of this pandemic related to mismanaged plastic waste is unknown. However, understanding the changing landscape and alarming need for effective plastic waste management, the government of India has proposed certain changes to prohibit imports, handling, manufacturing and use of single-use plastics in the country. This is in line with the government's intent to phase out single-use plastic by 2022. Considering this, this chapter highlights the changes in the rules and regulations in India related to plastic waste management and its effects on various sectors of business. © 2023 by Emerald Publishing Limited.

Characterization of the Products of the Catalytic Pyrolysis of Discarded COVID-19 Masks over Sepiolite

This research aims to develop a new strategy to valorize wasted COVID-19 masks based on chemical recycling by pyrolysis to convert them into useful products. First, surgical and filtering face piece masks, as defined in Europe by the EN 149 standard (FFP2), were thermally pyrolyzed at temperatures of 450, 500, and 550 °C, and the yields of valuable solid (biochar), liquid (biooil), and syngas products and their characteristics were determined. At low temperatures, biochar formation was favored over biooil and syngas production, while at high temperatures the syngas product yield was enhanced. The highest yield of biooil was found at a pyrolysis temperature of 500 °C, with both surgical and FFP2 masks achieving biooil yields of 59.08% and 58.86%, respectively. Then, the pyrolysis experiments were performed at 500 °C in a two-stage pyrolysis catalytic reactor using sepiolite as a catalyst. Sepiolite was characterized using nitrogen adsorption–desorption isotherms and Fourier-transform infrared spectroscopy. Results showed that the two-stage process increased the final yield of syngas product (43.89% against 39.52% for surgical masks and 50.53% against 39.41% for FFP2 masks). Furthermore, the composition of the biooils significantly changed, increasing the amount of 2,4-Dimethyl-1-heptene and other olefins, such as 3-Eicosene, (E)-, and 5-Eicosene, (E)-. Additionally, the methane and carbon dioxide content of the syngas product also increased in the two-stage experiments. Ultimately, the effect of sepiolite regeneration for its use in consecutive pyrolysis tests was examined. Characterization data showed that, the higher the use-regeneration of sepiolite, the higher the modification of textural properties, with mainly higher changes in its pore volume. The results indicated that the pyrolysis of face masks can be a good source of valuable products (especially from biooil and syngas products). © 2023 by the authors.

Solid waste management during the COVID-19 pandemic

The outbreak of COVID-19 is affecting the waste management, which is gaining increasing concerns all over the world. The waste generated during the pandemic is completely different from that of the normal in composition and property (i.e., plastic waste), and it possibly contains various virus, which suggests that it should be handled and disposed carefully. This chapter introduces the current status of waste management during the pandemic. The points for collection, transportation, treatment/disposal during the pandemic were summarized in order to provide reference for other countries in the post-epidemic era of solid waste management. © 2023 Elsevier Inc. All rights reserved.

Insights on the current status of effective strategies for waste management in COVID-19 pandemic: challenges and opportunities

A large number of people got infected and many lost their lives due to COVID-19. The increased volume and source-shuffling of the waste generated during the pandemic have challenged the current waste management facilities. The major sources of infectious waste not only include hospitals but also houses and quarantine facilities that lack in source-management thereby increasing the spread of the virus. This article focuses on waste collection and disposal techniques as major aspects of COVID-19 waste management. Also, it discusses the various waste disinfection technologies along with waste management strategies formulated by different organisations. The non-pharmaceutical intervention strategies have also been identified. Alongside this, various challenges and opportunities in COVID-19 waste management are reviewed. Accordingly, recommendations to achieve efficient waste management are stated. Waste management in case of such a pandemic requires proper segregation, storage, collection and treatment. Usage of multiple processes like pyrolysis, chemical treatment, microwave and radio wave is needed to be found for treatment of infectious waste. Increased amount of mixed waste creates the need to have method that is flexible enough. Large amount of PPE waste needs to be taken care of. Development of materials that can provide hygiene and have recyclability is essential. © 2023 Indian Institute of Chemical Engineers.

Photoredox-Catalyzed Plastic Waste Conversion: Nonselective Degradation versus Selective Synthesis

Plastic waste pollution is becoming one of the most pressing environmental crises due to the large-scale production without satisfactory recycling schemes, especially with the outbreak of the COVID-19 pandemic in recent years. Upcycling of plastic waste into valuable chemicals powered by solar energy presents a substantially untapped opportunity to turn waste into treasure. In this review, the fundamental principles from plastic nonselective degradation to selective synthesis are first clarified. Then, we aim to outline the representative recent advances in photoredox-based catalytic plastic waste conversion. Particular emphasis is placed on the valorization of plastic waste regarding nonselective degradation versus selective synthesis. Finally, we present challenges and individual insights for further exploration of the plastic waste conversion domain. It is anticipated that this timely and critical review would provide an instructive direction and foresight on the selective conversion of plastics to value-added chemical feedstocks, thus stimulating the development of a circular and sustainable plastic economy in the coming decades. © 2023 American Chemical Society.

The Environmental Impacts of Disposable Nonwoven Fabrics during the COVID-19 Pandemic: Case Study on the Francesc de Borja Hospital.

Hospitals generate huge amounts of nonwoven residues daily. This paper focused on studying the evolution of nonwoven waste generated in the Francesc de Borja Hospital, Spain, over the last few years and its relation to the COVID-19 pandemic. The main objective was to identify the most impacting pieces of nonwoven equipment in the hospital and to analyze possible solutions. The carbon footprint of the nonwoven equipment was studied through a life-cycle assessment. The results showed an apparent increase in the carbon footprint in the hospital from 2020. Additionally, due to the higher annual volume, the simple nonwoven gown used primarily for patients had a higher carbon footprint over a year than the more sophisticated surgical gowns. It can be concluded that developing a local circular economy strategy for medical equipment could be the solution to avoid the enormous waste generation and the carbon footprint of nonwoven production.

Can disposable masks be worn more than once?

Disposable facemasks are a primary tool to prevent the transmission of SARS-COV-2 during the COVID-19 pandemic. However, plastic waste generated from their disposal represents a significant environmental problem that can be reduced by maximizing the service life of disposable masks. We evaluated the effect of repeated wearing on the fitted filtration efficiency (FFE) of N95, KF94, KN95, and procedure/surgical masks. The FFEs of masks were compared following extended wearing with and without washing. Results reveal that most disposable facemasks can retain a high level of their baseline FFE after extended wearing, even after 40 h of wearing. Laundering disposable masks degraded FFE in some instances. We conclude that the durability of disposable facemask performance is considerably longer than their intended single use indication, suggesting that reusing disposable masks is a safe means of reducing plastic waste in the environment.

Upcycling disposable face masks into fuel range iso-alkanes through hydropyrolysis coupled with vapor-phase hydrocracking

The COVID-19 pandemic has resulted in an alarming accumulation of plastic waste. Herein, an integrated hydropyrolysis and hydrocracking process was performed to upcycle disposable masks into fuel-range iso-alkanes over carbon supported ruthenium (Ru/C). Experimental results indicated that catalyst type significantly affected product distribution during the hydropyrolysis and vapor-phase hydrocracking of disposable masks. Compared with zeolites-induced catalytic cascade process where up to ∼25.9 wt% yield of aromatic hydrocarbons such as toluene and xylenes were generated, a ∼82.7 wt% yield of desirable iso-alkanes with a high C5–C12 gasoline selectivity of 95.5% was obtained over Ru/C under 550 °C hydropyrolysis temperature and 300 °C hydrocracking temperature at 0.2 MPa H2. The cascade hydropyrolysis and hydrocracking process also exhibited high adaptability and flexibility in upcycling single-use syringes, food packaging, and plastic bags, generating 79.1, 81.6, and 80.3 wt% yields of fuel range iso/n-alkanes, respectively. This catalytic cascade hydrotreating process provides an efficient and effective approach to convert pandemic-derived plastic waste into gasoline-range fuel products. © 2022 Elsevier Ltd

Microplastics in the Ecosystem: An Overview on Detection, Removal, Toxicity Assessment, and Control Release

In recent decades, the accumulation and fragmentation of plastics on the surface of the planet have caused several long-term climatic and health risks. Plastic materials, specifically microplastics (MPs;sizes < 5 mm), have gained significant interest in the global scientific fraternity due to their bioaccumulation, non-biodegradability, and ecotoxicological effects on living organisms. This study explains how microplastics are generated, transported, and disposed of in the environment based on their sources and physicochemical properties. Additionally, the study also examines the impact of COVID-19 on global plastic waste production. The physical and chemical techniques such as SEM-EDX, PLM, FTIR, Raman, TG-DSC, and GC-MS that are employed for the quantification and identification of MPs are discussed. This paper provides insight into conventional and advanced methods applied for microplastic removal from aquatic systems. The finding of this review helps to gain a deeper understanding of research on the toxicity of microplastics on humans, aquatic organisms, and soil ecosystems. Further, the efforts and measures that have been enforced globally to combat MP waste have been highlighted and need to be explored to reduce its potential risk in the future. © 2022 by the authors.

A comprehensive review on the production of alternative fuel through medical plastic waste

This paper aims to critically review the production of alternative fuels through medical plastic waste. In the recent past, medical plastic waste has been disposed of and incinerated in the dumping yards, which is the main cause of the threat of infection and environmental hazards. Adopting proper waste management and the appropriate technology like the 5R's (refuse, reduce, reuse, repurpose, and recycle) may significantly improve the ecosystem. Moreover, the 5R's is a comprehensive approach that can be applied, either awareness of stakeholders or enforcement mandate and regulation by the government. The current review suggested the possible route for converting medical-plastic waste into drop-in fuel and value-added products to minimize the waste through suitable technology. In this, the pyrolysis technique plays an important role which is more ecologically friendly, effective and produces minimal pollutants. It has been observed that using COVID medical waste management (CMWM) technology, 70–80 % plastic pyrolysis oil (PPO), 10–15% bio-char, and gaseous fuel can be extracted. As per the ASTM, the extracted PPO is a potential feedstock for the CI engine fuel. This review work provides a suitable solution for CMWM and improves the quality of medical infrastructure for sanitation in a sustainable mode. © 2022 Elsevier Ltd

Thermo-Chemical conversion of polyolefin-based facemask using bench-scale pyrolysis system

The generation of personal protective equipment (PPE) waste due to the impact of COVID has increased multi-fold globally. In this study, pyrolysis of polyolefin-based PPEs was carried out using a bench-scale reactor of 2 kg per batch capacity. Thermogravimetric (TGA) analysis of face masks was carried out to identify the optimal parameters for the pyrolysis process. Different combinations of catalysts (ZSM-5 and montmorillonite), catalyst to feed ratio (2.5% and 5%), experiment duration (2 h and 3 h), and process temperature (450 degrees C and 510 degrees C) were tested to determine the maximum yield of the pyrolysis oil. The oil and char obtained from the pyrolysis of PPEs were analyzed for its gross calorific value (GCV), elemental analysis (CHNS), and chemical composition. Based on the experiments conducted, the optimum pyrolysis temperature, catalyst, catalyst to feed ratio, and batch time for maximum oil yield (55.9% w/w) were determined to be 510 degrees C, ZSM-5, 5%, and 2 hours, respectively. Oil was free of sulfur and had a calorific value of 43.7 MJ/kg, which is comparable to commercial diesel fuel and makes it a suitable alternative fuel for ships, boilers, and furnaces.

Lifetime prediction of non-woven face masks in ocean and contributions to microplastics and dissolved organic carbon

This study explored the degradation behavior of three types of disposable face masks in simulated seawater via the accelerated aging experiments. Microplastics (MPs) and dissolved organic carbon (DOC) were monitored in UV- and thermal-treated mask suspensions and their concentrations increased slowly in the early stage at 50 ℃ and 58 ℃. Owing to the high energy supply, the release rates of MPs and DOC at 76 ℃ were much faster than the above two temperatures. The time-temperature superposition principle (TTSP) was used to superpose the MPs/DOC release kinetics from other tested temperatures to the reference temperature and its applicability was verified by the similar activation energy. Then, a release kinetics model was established and fitted well with the superposed MP data (R2 ≥ 0.96). Since less than 0.1 % of carbon was leached, the superposed DOC data was roughly modelled by the exponential function (R2 ≥ 0.90). According to the TTSP and the established kinetics models, about 15 years were estimated to decompose half of a certain marine mask waste, together with leaching 0.21 ± 0.02 mg∙g-mask−1 of DOC. If mask consumption remains the same before 2025, they would contribute 40000–230000 tonnes of MPs and 13–97 tonnes of DOC to the ocean by 2040. © 2022

From city to sea: Spatiotemporal dynamics of floating macrolitter in the Tiber River

Rivers are undoubtedly the main pathway of waste dispersed in the environment that from land reaches oceans and seas increasing the amount of marine litter. Major cities are a great source of riverine litter as large urbanization can originate pressure on the integrated waste management resulting in litter entering the rivers. Within this study, we aim to investigate the dynamic of floating riverine macrolitter (items >2.5 cm) in the city of Rome before it reaches the sea by assessing the composition, amount, and seasonal trends of litter transported from the urban centre to the main river mouth of Tiber River. Visual surveys for a whole year (March 2021–February 2022) were conducted from two bridges, Scienza Bridge (in the city) and Scafa Bridge (at the main river mouth) and followed JRC/RIMMEL protocol for riverine litter monitoring. Overall, similar litter composition was observed from the city centre to the mouth with a prevalence of plastic material, mainly related to fragmentation process (i.e. plastic pieces) and single use items, mainly in food and beverage sectors. An extrapolated annual loading of 4 × 105 items/year was estimated at the main mouth of Tiber River. The litter flux seems to be influenced by the seasonal variability and hydrometeorological parameters. The frequency of size classes decreases with increasing size in both sites, and more than half of the recorded items were below 10 cm. Specific categories belonging to "other plastics” have been reported related to anti-Covid-19 behaviour such as face masks and beverage sector, e.g. bottle lids and rings. The main colour of plastics was white, suggesting weathering process of floating riverine litter. This study contributes to increasing knowledge of the origin, composition and spatiotemporal dynamics of riverine floating litter from the city and entering the sea. © 2022 Elsevier B.V.

A review on production and application of activated carbon from discarded plastics in the context of ‘waste treats waste'

In the post-COVID scenario, the annual increase in plastic waste has taken an upsurge due to the disposal of plastic masks, gloves and other protective equipment. To reduce the plastic load ending up in landfills and oceans or dumped at roadsides, the potential of using plastic polymers in different sectors has been investigated over the years leading to their potential application in pavement laying, concrete industry, fuel generation and production of carbon-based compounds among which activated carbons (AC) is a prime example. As one of the most recommended adsorbents for removing contaminants from water and adsorbing greenhouse gases, AC creates a potential sector for using discarded plastic to further treat pollutants and approach closer to a circular economy for plastics. This paper analyses the production process, the effect of production parameters on AC characteristics and properties that aid in adsorption. The interdependence of these factors determines the surface area, porosity, relative micropore and mesopore volume, thereby defining the utility for removing contaminant molecules of a particular size. Furthermore, this work discusses the application of AC along with a summary of the earlier works leading to the existing gaps in the research area. Production costs, formation of by-products including toxic substances and adsorbate selectivity are the major issues that have restricted the commercial application of this process towards its practical use. Research aimed at valorization of plastic waste into ACs would minimize the solid waste burden, along with treating other pollutants. © 2022 Elsevier Ltd

Environmental and Human Health Impact of Disposable Face Masks During the COVID-19 Pandemic: Wood-Feeding Termites as a Model for Plastic Biodegradation.

The ongoing COVID-19 pandemic has resulted in an unprecedented form of plastic pollution: personal protective equipment (PPE). On the eve of the COVID-19 pandemic, there is a tremendous increase in the production of plastic-based PPE. To control the spread of the virus, face masks (FMs) are used as primary PPE. Thus, the production and usage of FM significantly increased as the COVID-19 pandemic was still escalating. The primary raw materials for the manufacturing of FMs are non-biodegradable synthetic polymers derived from petrochemicals. This calls for an urgent need to develop novel strategies for the efficient degradation of plastics. Furthermore, most of these masks contain plastic or other derivatives of plastic. The extensive usage of FM generates millions of tons of plastic waste for the environment in a short span of time. However, their degradation in the environment and consequences are poorly understood. Therefore, the potential impacts of disposable FM on the environment and human health during the COVID-19 pandemic are clarified in the present study. Despite structural and recalcitrance variations, lignocellulose and plastic polymers have physicochemical features, including carbon skeletons with comparable chemical bonds as well as hydrophobic properties in amorphous and crystalline regions. In this review, we argue that there is much to be learned from termites by transferring knowledge from research on lignocellulose degradation by termites to that on plastic waste.