A comprehensive analysis of e-waste legislation worldwide

Assessment of direction changes in waste electrical and electronic equipment management in Poland

A growing amount of waste electrical and electronic equipment (WEEE) indicates the need to verify the effectiveness of its management both nationally and globally. An analysis of the WEEE economy in Poland conducted over 5 years confirmed a 16.64% increase in the mass of collected equipment. The maximum annual mass of electrical and electronic equipment introduced to the market during this period was 607,240 Mg, with the average value exceeding 500,000 Mg. The WEEE category with the largest collected mass was waste code 20 01 36, which exceeded 235,000 Mg, whilst the highest waste weight accumulation rate of 45.98 kg per capita was recorded in one of the smallest voivodeships in Poland. This result showed the diversity of WEEE accumulation on a national scale. Overall, a noticeable increase in the WEEE accumulation rate has occurred as Poland's gross domestic product has increased, despite a decreasing population. An analysis based on the waste accumulation indicators, including socioeconomic factors, confirmed the need to develop forms of WEEE recovery and recycling to transition to a circular economy and promote the synergy of activities amongst all players in WEEE management.

Ecotoxicological impacts of landfill sites: Towards risk assessment, mitigation policies and the role of artificial intelligence

Waste disposal in landfills remains a global concern. Despite technological developments, landfill leachate poses a hazard to ecosystems and human health since it acts as a secondary reservoir for legacy and emerging pollutants. This study provides a systematic and scientometric review of the nature and toxicity of pollutants generated by landfills and means of assessing their potential risks. Regarding human health, unregulated waste disposal and pathogens in leachate are the leading causes of diseases reported in local populations. Both in vitro and in vivo approaches have been employed in the ecotoxicological risk assessment of landfill leachate, with model organisms ranging from bacteria to birds. These studies demonstrate a wide range of toxic effects that reflect the complex composition of leachate and geographical variations in climate, resource availability and management practices. Based on bioassay (and other) evidence, categories of persistent chemicals of most concern include brominated flame retardants, per- and polyfluorinated chemicals, pharmaceuticals and alkyl phenol ethoxylates. However, the emerging and more general literature on microplastic toxicity suggests that these particles might also be problematic in leachate. Various mitigation strategies have been identified, with most focussing on improving landfill design or leachate treatment, developing alternative disposal methods and reducing waste volume through recycling or using more sustainable materials. The success of these efforts will rely on policies and practices and their enforcement, which is seen as a particular challenge in developing nations and at the international (and transboundary) level. Artificial intelligence and machine learning afford a wide range of options for evaluating and reducing the risks associated with leachates and gaseous emissions from landfills, and various approaches tested or having potential are discussed. However, addressing the limitations in data collection, model accuracy, real-time monitoring and our understanding of environmental impacts will be critical for realising this potential.

Target setting and performance analysis: Promoting e-waste collection in China under the collection target responsibility models

The increasing volume of electronic waste (e-waste) poses significant challenges for efficient collection in China. Despite many measures were taken over the past two decades, the e-waste collection rate was still not high. To this end, the Chinese government issued a new policy, the collection target responsibility (CTR) policy. Under the CTR policy, however, it is essential for participants to know how to share the responsibility of collection and how much reasonable targets are set to ensure the efficiency of the collection models. Therefore, the purpose of this paper is to explore the determination of optimal collection targets and the corresponding performance from the perspective of responsibility sharing to support the successful implementation of the CTR. Firstly, the study focuses on participants including the government, manufacturers, and recyclers, and develops three CTR models, independent collection model, government cost-sharing model, and enterprise collaboration model. Secondly, collection target equations for each model are established by employing dynamic differential game analysis, and corresponding collection performances are derived. Thirdly, through practical case simulations, the evolution of collection performance is dynamically analyzed to determine reasonable collection targets for the three models, as 23.8%, 32.3%, and 34.4%, respectively. The findings highlight the effectiveness of CTR in improving e-waste collection targets and performance, with the highest levels attained when the collection responsibilities are shared by government cost-sharing and enterprise collaboration. This study provides theoretical support for setting reasonable collection targets under CTR, and assists decision-makers in developing targeted CTR implementation measures.

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

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

A review of heavy metal risks around e-waste sites and comparable municipal dumpsites in major African cities: Recommendations and future perspectives

In Africa, the effects of informal e-waste recycling on the environment are escalating. It is regularly transported from developed to developing nations, where it is disassembled informally in search of precious metals, thus increasing human exposure to harmful compounds. Africa has a serious problem with e-waste, as there are significant facilities in Ghana and Nigeria where imported e-waste is unsafely dismantled. however, because they are in high demand and less expensive than new ones, old electronic and electrical items are imported in large quantities, just like in many developing nations. After that, these objects are frequently scavenged to recover important metals through heating, burning, incubation in acids, and other techniques. Serious health hazards are associated with these activities for workers and individuals close to recycling plants. At e-waste sites in Africa, there have been documented instances of elevated concentrations of hazardous elements, persistent organic pollutants, and heavy metals in dust, soils, and vegetation, including plants consumed as food. Individuals who handle and dispose of e-waste are exposed to highly hazardous chemical substances. This paper examines heavy metal risks around e-waste sites and comparable municipal dumpsites in major African cities. Elevated concentrations of these heavy metals metal in downstream aquatic and marine habitats have resulted in additional environmental impacts. These effects have been associated with unfavourable outcomes in marine ecosystems, such as reduced fish stocks characterized by smaller sizes, increased susceptibility to illness, and decreased population densities. The evidence from the examined studies shows how much e-waste affects human health and the environment in Africa. Sub-Saharan African nations require a regulatory framework that includes specialized laws, facilities, and procedures for the safe recycling and disposal of e-waste.

Critical factors for implementing collection target responsibility in e-waste collection in China: A DEMATEL-ISM analysis

The Collection Target Responsibility (CTR) is the direction for the proper management of e-waste reuse and recycling. Despite its potential, the CTR policy is still in its infancy in China and faces significant challenges to its effective implementation. There are a few studies that have systematically identified and analyzed the factors that influence the application of CTR to e-waste collection systems in China. This study proposes a comprehensive process that considers collection targets and behaviors to develop the critical factors (CFs) involved in e-waste collection under CTR by participants including government, manufacturers and recyclers. The Decision-making Trial and Evaluation Laboratory and Interpretative Structural Modeling (DEMATEL-ISM) method was applied to analyze these CFs. The findings show that the development of policy and regulation is the root factor influencing the implementation of CTR in China, both in terms of collection targets and behaviors. Incentives and regulation of government, collection channels, and benefits of manufacturers and recyclers are important CFs that participants consider when adopting CTR and should be prioritized. This study not only contributes to the literature on e-waste collection under CTR, but also provides valuable insights for decision-makers to improve the performance of e-waste collection practices.

A review of various strategies in e-waste management in line with circular economics

Waste management of electrical and electronic equipment has become a key challenge for electronics manufacturers due to globalization and the rapid expansion of information technology. As the volume of e-waste grows, legal departments lack the infrastructure, technology, and ability to collect and manage it environmentally soundly. Government laws, economic reasons, and social issues are important considerations in e-waste management. The circular economy concept is built on reusing and recycling goods and resources. A novel idea called the circular economy might prevent the negative consequences brought on by the exploitation and processing of natural resources while also having good effects such as lowering the demand for raw materials, cutting down on the use of fundamental resources, and creating jobs. To demonstrate the significance of policy implementation, the necessity for technology, and the need for societal awareness to build a sustainable and circular economy, the study intends to showcase international best practices in e-waste management. This study uses circular economy participatory implementation methods to provide a variety of possible approaches to assist decision-makers in e-waste management. The purpose of this article is to review the most accepted methods for e-waste management to emphasize the importance of implementing policies, technology requirements, and social awareness in creating a circular economy. To conclude, this paper highlights the necessity of a common legal framework, reform of the informal sector, the responsibility of different stakeholders, and entrepreneurial perspectives.

One-step separation of tin from e-waste by a chemical vapor transport process (CVT): Preparation of nano-SnO2

E-waste is a valuable resource for the recovery of secondary metals. However, traditional methods only focused on the extraction of Cu and noble metals (Au, Ag, etc.), and significant tin (Sn) loss occurred during the smelting or the leached. In this paper, a novel chemical vapor transport (CVT) process was proposed to separate and recycle Sn from e-waste to prepare nano-SnO₂. The effect of roasting parameters on Sn volatilization and characterization of nano-SnO₂ were investigated using thermodynamic analysis, XRD, SEM, TEM, etc. The results indicated that Sn volatilization of 92.8 % was obtained under optimal roasting parameters under CO-CO₂-N₂ atmosphere. In addition, nano-SnO₂ with a crystallinity of 99.9 %, an average grain size of 24.8 nm and a specific surface area of 97.9 m²/g was synthesized successfully.

Global research into the relationship between electronic waste and health over the last 10 years: A scientometric analysis

Introduction

The aims of this research were to conduct the first holistic and deep scientometric analysis of electronic waste and health and provide with the prediction of research trends and hot topics.

Method

A comprehensive literature search was conducted via the Web of Science Core collection databases on 26 August 2022 to identify all articles related to electronic waste and health. A total of 652 records have been extracted from the Web of Science after applying inclusion and exclusion criteria and were analyzed using bibliometrix software of R-package, VOSviewer, and CiteSpace, visualized by tables and diagrams.

Result

The number of publications and total citations had shown a general growth trend from 2012 to 2021, with an average annual growth rate of 23.74%. Mainland China was the significant nation with the greatest number of publications, citations, and international links. The journal publishing the most was "Science of the Total Environment" (n = 56). Huo X and Hu XJ were the top two author contributing to this field with the highest h-index (23). Over time, the focus in this field shifted to exposure to heavy metal, polychlorinated biphenyls, polybrominated biphenyl ethers, and poly- and perfluorinated alkyl substances from electronic waste, and managements, such as hydrometallurgy.

Discussion

By this scientometric analysis, we found that the most active country, journal, organization and author contributing to this filed, as well as high impact documents and references and research hotspots. Also, we found that the hotspots might be exposure to toxic substances from electronic waste procession, its impact on human health and relevant managements. And evironmentally friendly materials to replace heavy metal mate rials, and environmentally friendly and effective recycling methods of electronic waste need to be further studied.

Green and Social Regulation of Second Hand Appliance Markets: the Case of Air Conditioners in the Philippines

Second hand markets for appliances such as air conditioners are largely unregulated in many low and middle income countries this far. Energy and climate goals may require a speedy phase-out of old appliances, whereas material resource and social concerns may call for repairing and reusing air conditioners as long as possible. Demand for space cooling is soaring globally, increasing regulatory pressure. In middle income countries such as the Philippines, the market for second hand room air conditioners is sizeable. This study targets the question when and how to regulate the market for used air conditioners to balance green and social goals. It analyses the second hand market for air conditioners in Metro Manila, uncovering the general supply chain, business models and customers as well as energy efficiency, refrigerant and repair practices. The study draws on qualitative interviews with 10 experts and 29 retailers and technicians active in the semi-formal second hand market for air conditioners. Available information of lifecycle analyses is taken into account, but the focus of this contribution lies on social impacts of potential regulation. Overall, short-to-medium interventions in the second hand market are required to balance environmental and social goals that target the different players in the market: construction industry, brokers, retailers and technicians, customers and scrap dealers. Neither a complete ban nor delaying or foregoing regulation is advisable. Specific policy recommendations are derived.

Identification of specific halogenated polycyclic aromatic hydrocarbons in surface soils of petrochemical, flame retardant, and electronic waste dismantling industrial parks

Halogenated polycyclic aromatic hydrocarbons (Cl/Br-PAHs) have received tremendous attention due to their high toxicity. To identify the emission pattern of Cl/Br-PAHs from various industrial productions, understand the formation mechanisms and the influence on the surroundings, this study investigated the surface soils of three typical industrial parks. Generally, traces of Cl-PAHs were much lower than Br-PAHs. The mean Cl-PAH concentrations followed the trend of petrochemical industrial park (3.12 ng/g), brominated flame retardant (BFR) manufacturing park (1.48 ng/g), and electronic waste dismantling park (0.26 ng/g). However, the BFR manufacturing park had the highest mean Br-PAH concentration (21.6 ng/g), significantly higher than the other two parks. Generally, higher levels of the chemicals were found in the parks than in their surroundings, except for the electronic waste dismantling park. The massive addition of chlorine additives in crude oil and its by-products, plus the enormous quantity of brominated brines used in BFR productions, favor Cl/Br-PAH formation. Analyzing the homolog compositions of Cl/Br-PAHs suggested that 3- or 4-ring Cl/Br-PAHs were typically come from the petrochemical industrial park and electronic waste dismantling park. Contrarily, 4- or 5-ring Cl/Br-PAHs were predominantly come from the BFR manufacturing activity. This study provides fingerprints to trace the Cl/Br-PAH emissions during industrial production and analyzes the formation mechanism.

Managing e-waste from a closed-loop lifecycle perspective: China's challenges and fund policy redesign

E-waste is one of the fastest growing streams of solid waste globally, and its effective management has become a focused issue, which requires a deep understanding of the core guiding theory of extended producer responsibility (EPR). Over the past 20 years, China, one of the world's largest producers of electrical and electronic equipment (EEE), has made great efforts to improve e-waste management along with the massive generation of e-waste. In 2012, China implemented a unique EPR-based e-waste fund policy. However, the fund policy is unsustainable due to the challenges of non-closed resource use, informal recycling, and fund imbalance. Beginning with an overview of these challenges, this paper focuses on redesigning the fund policy from a closed-loop lifecycle perspective in order to maintain a balanced development of the resource use loop and the fund system in China's ten-year plan. In doing so, two EPR instruments, recycling content standards and consumer-oriented deposits, are added to the current fund policy. Subsequently, three extension scenarios alternately changed a critical parameter of the model to test the impact on sustainable capabilities. In this way, the sustainable supply of funds and secondary resources for the e-waste industry can be established in China and effectively demonstrate solid waste management in developing countries.

Digital environment: An evolutionary component in environmental health

The COVID-19 pandemic has hastened the progress of digitalization where the public is forced to embrace paradigm shifts on how we function in a digital society. The way we work, learn, live, and play daily has drastically changed with the revolution of digital systems from their analog predecessor. This transformation warrants the digital environment as a social determinant of health. It comprises the whole continuum from the tangible aspects of the computing devices, their programing and information system, the network technologies connecting them, and the product of interactivity between people to people and people to the digital interface. Despite permeating the everyday life of each level of society, the digital environment has yet to be scrutinized comprehensively in terms of health. A review of the literature produces fragmented results where different specialties within and beyond the medical field lay claim to the various aspects of digitalization. We proposed five domains within the digital environment namely digital transformation, digital health, digital technology, digital identity, and digital media that exerts diversified pressure on the digital environment through human activities. Their subjacent linkage to human health and environmental impact is further discussed by using the DPSEEA framework. Challenges that crossed all domains were discussed including the widening gap of inequalities secondary to the limited availability of, and accessibility to digitalization. Considering the rapid speed at which we propel to a fully immersive virtual world, a timely transformation of environmental health to include the digital environment as part of its main components is inevitable.

Analysis of Critical Success Factors to Design E-waste Collection Policy in India: A Fuzzy DEMATEL Approach

The design of an e-waste collection policy is challenging, especially for a country like India, where the economy is a developing state, and there is a large diversity in socio-economic factors. The e-waste collection policy impacts the various stakeholders such as the manufacturer, the raw material producers, the assemblers, the retailers, the generator (households and bulk consumers), the scrap dealers, the smelters, the recyclers, and the regulators. The design of an e-waste collection policy needs to consider the appropriate set of Critical Success Factors (CSFs), which will maximise the e-waste collection providing business sustainability to the stakeholders while satisfying the environmental regulations in the operating locations. Twenty-three CSFs identified and categorised in six implication dimensions for the e-waste collection policy framework based on a literature survey and experts committee view. The fuzzy DEMATEL approach is employed to analyse the CSFs to design an e-waste collection policy in India from a comprehensive perspective. Cause and effect interrelationship is established among the CSFs, and also their impacts are evaluated to segregate the CSFs into cause group (prominent influencing and independent) and effect group (influenced and dependent). The CSFs such as technology involvement, green practices, environmental program, certification and licensing, public ethics and stakeholder's awareness for circular economy are prominent influencing CSFs for e-waste collection policy in India. The current study is expected to provide a platform for policymakers to design the e-waste collection policy.

A Review on Global E-Waste Management: Urban Mining towards a Sustainable Future and Circular Economy

The trending need for smarter electrical and electronic equipment (EEE) is surging globally by the year and is giving rise to huge amounts of outdated EEE going into landfills. This has caused enormous threats to our environment and the health of living beings due to its unsustainable ways of collection, treatment and disposal of waste EEE or E-waste. With increasing E-waste, the formal sectors lack infrastructure, technology and expertise required to collect and process the E-waste in an environmentally sound manner. This article is intended to bring out the global best practices in the field of E-waste management, to shed light on the importance of policy implementation, technology requirement and social awareness to arrive at a sustainable and circular economy. Although about 71% of the world’s populace has incorporated E-waste legislation, there is a need to enforce and implement a common legal framework across the globe. The article explains the gap created among the stakeholders and their knowledge on the roles and responsibilities towards a legalized E-waste management. It further explains the lack of awareness on extended producer responsibility (EPR) and producer responsibility schemes. Despite various legislations in force, numerous illegal practices such as acid leaching, open incineration, illegal dumping carried out by the informal sector are causing harm to the environment, natural resources and the safety of unorganized and unskilled labor. The article discusses the crucial need for awareness amongst stakeholders, consumer behavior and the global challenges and opportunities in this field to achieve a low-carbon, circular economy. To conclude, the article highlights the importance of common legal framework, EPR and licenses, transformation of the informal sector, benchmark technologies, responsibilities of various stakeholders and entrepreneurial opportunities to enhance the formal capacity. The article wholly advocates for transparency, accountability and traceability in the E-waste recycling chain, thus creating a greener environment and protecting our planet and natural resources for future generations.

Examining country development indicators and e-waste under the moderating effect of country development levels and e-waste policy

Purpose

The purpose of this paper is to investigate if country development indicators, i.e. gross domestic product per capita (GDPPC), literacy rate, internet penetration and urban population, influence the generation of e-waste on a global level. The moderation effect due to differences between countries in terms of absence or presence of e-waste policy and level of development is also checked.

Design/methodology/approach

This is an archival study that builds upon data from United Nations (UN), World Bank and Global E-waste Statistics Partnership. The authors did a path analysis comprising mediation and multigroup analyses to decipher the proposed rese arch model containing data from 172 countries.

Findings

The results indicate that GDPPC, literacy rate, internet penetration and urban population do not directly influence the generation of e-waste. However, higher internet penetration in developing countries leads to higher e-waste, while higher literacy rates in developed countries suppress e-waste generation. When it comes to e-waste policy, a higher urban population without a regulatory legal framework boosts higher e-waste. The authors observed that higher internet penetration leads to higher e-waste in the presence of e-waste policy as well.

Originality/value

This is the first study to include economic well-being indicators in elaborating e-waste generation, on a global scale. No previous study has observed differences between countries nested in e-waste policy and level of development.

Analysis of Households' E-Waste Awareness, Disposal Behavior, and Estimation of Potential Waste Mobile Phones towards an Effective E-Waste Management System in Dubai

During the recent decades, the world has seen ongoing economic and technological development which resulted in the generation of huge volumes of electrical and electronic waste (e-waste). In the Middle East, the United Arab Emirates (UAE) ranks among countries with large e-waste generation due to its consumers' high spending on electronic devices thereby resulting in a high obsolescence rate in the country. Accordingly, this study aims to analyze the e-waste management and recycling practices in the UAE. It takes Dubai as a case study and conducts a structured questionnaire to analyze households' awareness, consumption of electronic devices in general and mobile phones in particular, and the disposal behavior of e-waste. Waste mobile phones is taken as a key representative in this study, in which potential waste mobile phones is estimated using the Approximation 1 method in the period 2021-2030. Results from the survey illustrated gaps among households' awareness and disposal behavior of e-waste, where e-waste recycling rates were noticed to be low. Based on these gaps, strategies were proposed for an effective e-waste management system in the context of Dubai, and were supported by the proposal of an e-waste legislation framework in the UAE.

E-Waste Recycling and Resource Recovery: A Review on Technologies, Barriers and Enablers with a Focus on Oceania

Electronic e-waste (e-waste) is a growing problem worldwide. In 2019, total global production reached 53.6 million tons, and is estimated to increase to 74.7 million tons by 2030. This rapid increase is largely fuelled by higher consumption rates of electrical and electronic goods, shorter life cycles and fewer repair options. E-waste is classed as a hazardous substance, and if not collected and recycled properly, can have adverse environmental impacts. The recoverable material in e-waste represents significant economic value, with the total value of e-waste generated in 2019 estimated to be US $57 billion. Despite the inherent value of this waste, only 17.4% of e-waste was recycled globally in 2019, which highlights the need to establish proper recycling processes at a regional level. This review provides an overview of global e-waste production and current technologies for recycling e-waste and recovery of valuable material such as glass, plastic and metals. The paper also discusses the barriers and enablers influencing e-waste recycling with a specific focus on Oceania.

A Review on Printed Electronics: Fabrication Methods, Inks, Substrates, Applications and Environmental Impacts

Innovations in industrial automation, information and communication technology (ICT), renewable energy as well as monitoring and sensing fields have been paving the way for smart devices, which can acquire and convey information to the Internet. Since there is an ever-increasing demand for large yet affordable production volumes for such devices, printed electronics has been attracting attention of both industry and academia. In order to understand the potential and future prospects of the printed electronics, the present paper summarizes the basic principles and conventional approaches while providing the recent progresses in the fabrication and material technologies, applications and environmental impacts.

Ticking time bomb: implications of the COVID-19 lockdown on e-waste management in developing countries

The COVID-19 pandemic has altered the course of events globally since the outbreak of coronavirus disease (COVID-19) in late 2019 giving further credence to the long-standing belief that the world is indeed a global village. There have been different responses by countries to the raging pandemic including the imposition of lockdowns, quarantine and isolation. The imposition of lockdowns, whether full or partial, has not been without major consequences, which has led to information, communication and technological (ICT)-based measures to minimise the effect of the lockdown and as an alternative to physical interactions. The use of ICT devices to bridge the gaps created by the lockdown on schools, businesses and other sectors has led to the increased use of electronic devices. The challenge of electronic waste (e-waste) management in developing countries has been around for a while and the increased use of electronic devices is likely to compound the challenge during and post COVID-19. Whilst the development of ICT-based options as viable alternatives to face-to-face interactions may not be a negative development, this article argues that the existing frameworks are inadequate to manage the resultant increase in e-waste in most developing countries and that there is need now more than ever before for developing countries to exercise caution in embracing these ICT-based options without putting in place measures to ensure that there is increased capacity to manage and dispose of the e-waste created.

Bio-inspired gelatin/single-walled carbon nanotube nanocomposite for transient electrochemical energy storage: An approach towards eco-friendly and sustainable energy system

Wide-scale production of non-biodegradable e-waste from electrical appliances are causing great harm to the environment. The use of bio-polymer based nanomaterials may offer a promising approach for the fabrication of eco-friendly sustainable devices. In this work, gelatin/single walled carbon nanotube (Gel/SWCNT) nanocomposites were prepared by a simple and economic aqueous casting method. The effect of SWCNT on the structural, surface-morphological, electrical, and electrochemical properties of the nanocomposite was studied. Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscope (FESEM) showed an improved degree of interaction between the SWCNTs and Gel matrix. The surface wettability of the nanocomposites was found to be changed from hydrophilic to hydrophobic in nature due to the incorporation of SWCNTs into the Gel matrix. The incorporation of SWCNTs was also found to reduce the DC resistivity of the nanocomposite by 4 orders of magnitude. SWCNTs also increase the specific capacitance of the nanocomposite from 124 mF/g to 467 mF/g at a current density of 0.3 mA/g. The electrochemical impedance spectroscopy analysis revealed an increase of the pseudo-capacitance increased from 9.4 μF to 31 μF due to the incorporation of SWCNT. The Gel/SWCNT nanocomposite showed cyclic stability with capacitive retention of about 98% of its initial capacitance after completing 2000 charging/discharging cycles at a current density of 100 mA/g. The nanocomposite completely dissolves in water within 12 h, demonstrates it as a promising candidate for transient energy storage applications. The Gel/SWCNT nanocomposite may offer a new route for the synthesis of eco-friendly, biodegradable, and transient devices.

Green Practices for Global Supply Chains in Diverse Industrial, Geographical, and Technological Settings: A Literature Review and Research Agenda

With the rise in global consumption and the consequent intensive demand for global resources, the attention of scholars and practitioners towards greener supply chains has grown over the years. In this context, this study has two main aims. The first is to offer an up-to-date literature review of the ways in which sustainability is pursued in diverse settings, based on the sector, the geographical area, and the level of adoption of digital technologies of a company. The second aim is to identify the research gaps in this field, and to suggest directions for future investigations. The results of the structured literature review reveal that, although developed and developing countries tend to focus on different types of sustainable interventions, three factors are consistently considered to be crucial for the success of a sustainable initiative in global supply chains. These factors are the collaboration along the supply chain, the commitment of the top management, and the presence of environmentally-oriented policies or regulations. These three factors complicate the decision-making process that is needed to implement sustainable practices. Therefore, we suggest ways in which to design future research that better capture the real challenges of making environmentally conscious decisions, leveraging on the concepts of the Intertwined Supply Network (ISN) and the cognitive frame.

Environmentally friendly approach for the recovery of metallic fraction from waste printed circuit boards using pyrolysis and ultrasonication

Electronic waste (e-waste) with an annual growth rate of 3-5% is one of the fastest-growing waste streams. The unregulated accumulation and improper recycling can cause grave hazards to human beings and the environment. On the contrary, e-waste can be considered as a secondary source of metals and energy due to its high metal content and polymeric material. Thus, the present study demonstrates technology for the metallic fraction recovery and the production of valuable gases from e-waste. The process involves pyrolysis at a temperature range of 200 °C-600 °C in a fixed bed setup for 10-60 min. Under optimized operating conditions, 35 wt% combustible gases and 60 wt% solid product were obtained at a pyrolysis temperature of 400 °C in 20 min. The gaseous product consisted of CH₄, H₂, CO and CO₂, having the heating value 28 MJ/kg whereas, the solid product is a mixture of metals and other solid residue material. Treatment of the solid product using an ultrasonication process resulted in around 90 wt% recovery of metallic fraction, thereby leaving behind solid residue. Moreover, the transfer of precious metals (Au, Ag, Pd and Pt) was nearly 100% to the metallic fraction. This process combines mild temperature pyrolysis and ultrasonication process to provide a solution for efficient management of e-waste, metallic fraction recovery and valuable gases production.