Generation Of Electronic Waste Research Articles

Hydrophobic deep eutectic solvent-based vortex-assisted dispersive liquid–liquid microextraction with UV–visible spectrophotometry for copper determination in waste printed circuit boards

ABSTRACT Nearly all electronic devices utilise Printed Circuit Boards (PCBs), which contribute significantly to the generation of electronic waste (e-waste). They are rich in metal content, with copper being present in higher percentages. In this work, a simple, efficient and environment-friendly pre-concentration technique was developed, using hydrophobic deep eutectic solvent as an extractant in vortex-assisted dispersive liquid–liquid microextraction. This pre-concentration technique is coupled with spectrophotometry for the determination of copper in PCBs. The complexing agent, sodium diethyl di-thiocarbamate (DDTC), and copper formed a complex in the 2–3 pH range. The Cu-DDTC complex was vortexed for 1 min at 2800 rpm to extract in hydrophobic DES. The sediment was analysed using a UV–Visible spectrophotometer at λ max 435 nm. The optimisation parameters, including pH, extraction solvent selection and its volume, concentration and volume of chelating agent, interference of forein ios, etc., have been assessed. Analytical figures of merit such as limit of detection (1.98 μg/L), limit of quantification (5.9 μg/L), relative standard deviation (3.4%) and enrichment factor (10) have been obtained under optimal experimental conditions. The method was validated by a certified copper solution and applied successfully to determine copper in waste PCBs of personal computers.

Advancing green computing: Practices, strategies, and impact in modern software development for environmental sustainability

Advancing Green Computing: Practices, Strategies, and Impact in Modern Software Development for Environmental Sustainability explores the evolving landscape of green computing within the realm of software development, emphasizing the imperative for environmentally sustainable practices. In response to escalating environmental concerns, the computing industry is undergoing a paradigm shift towards reducing its carbon footprint and mitigating ecological impacts. This shift is particularly crucial in software development, given its pervasive influence on technological ecosystems. The review delves into the multifaceted dimensions of green computing, elucidating various practices and strategies that are instrumental in fostering environmental sustainability. From optimizing code efficiency to embracing energy-efficient computing architectures, the review underscores the diverse approaches available to software developers in minimizing resource consumption and carbon emissions. Furthermore, it examines the broader ramifications of these practices, emphasizing their potential to reshape the software industry's ecological footprint and contribute to global efforts for environmental conservation. Moreover, the review highlights the symbiotic relationship between green computing and modern software development methodologies. It elucidates how principles such as agile development and DevOps can be synergistically integrated with green computing practices to enhance sustainability throughout the software development lifecycle. By adopting an interdisciplinary approach that integrates environmental considerations into software design, development, and deployment processes, organizations can catalyze transformative changes towards a greener computing ecosystem. The review also investigates the tangible impact of green computing practices on environmental sustainability metrics. Through case studies and empirical analyses, it showcases the efficacy of various strategies in reducing energy consumption, carbon emissions, and electronic waste generation. Additionally, it discusses the economic and societal benefits accrued from adopting environmentally sustainable practices, ranging from cost savings to enhanced corporate social responsibility. Advancing Green Computing: Practices, Strategies, and Impact in Modern Software Development for Environmental Sustainability provides a comprehensive overview of the evolving landscape of green computing within the context of software development. It elucidates the myriad opportunities and challenges associated with fostering environmental sustainability in the computing industry and underscores the transformative potential of integrating green computing principles into modern software development practices.

Quantitative identification of the co-exposure effects of e-waste pollutants on human oxidative stress by explainable machine learning

Global electronic waste (e-waste) generation continues to grow. The various pollutants released during precarious e-waste disposal activities can contribute to human oxidative stress. This study encompassed 129 individuals residing near e-waste dismantling sites in China, with elevated urinary concentrations of e-waste-related pollutants including heavy metals, polycyclic aromatic hydrocarbons (PAHs), organophosphorus flame retardants (OPFRs), bisphenols (BPs), and phthalate esters (PAEs). Utilizing an explainable machine learning framework, the study quantified the co-exposure effects of these pollutants, finding that approximately 23% and 18% of the variance in oxidative DNA damage and lipid peroxidation, respectively, was attributable to these substances. Heavy metals emerged as the most critical factor in inducing oxidative stress, followed by PAHs and PAEs for oxidative DNA damage, and BPs, OPFRs, and PAEs for lipid peroxidation. The interactions between different pollutant classes were found to be weak, attributable to their disparate biological pathways. In contrast, the interactions among congeneric pollutants were strong, stemming from their shared pathways and resultant synergistic or additive effects on oxidative stress. An intelligent analysis system for e-waste pollutants was also developed, which enables more efficient processing of large-scale and dynamic datasets in evolving environments. This study offered an enticing peek into the intricacies of co-exposure effect of e-waste pollutants.

Identification of Electronic Waste (E-Waste) generation from the household and non-household sectors in Indonesia and its sustainable management system

The rapid development of technology has spurred competition among electronics manufacturers to innovate. The resulting electronic waste (e-waste) has potential hazards due to its composition. The prediction of e-waste generation is carried out using the Delay Model method, modified by applying end-of-life (EoL) value to the lifespan to adjust Indonesian society’s treatment of e-waste. The calculations show that the prediction of hazardous material from Indonesia’s household sector will reach 16,653.73 tonnes in 2040, while the non-household sector comes to 25,391.72 tonnes in 2040. The most e-product produced from the household sector is TV with 3,763.74 tonnes, while the non-household sector is also dominated by TV with 23,380.52 tonnes in 2040. The composition of materials obtained from e-waste, in general, is 1% hazardous materials, 31% ferrous metal, then 27% glass and plastic materials, 6% non-ferrous metals, and 8% other materials. Thus, the total generation of e-waste will reach 4,204,545.43 tonnes, and the hazardous components in e-products only reach 42,045.45 tonnes or about 1% of the total e-product generation. In the future, it is necessary to integrate and formalize the handling of e-waste from the informal sector, which has been developing into the formal sector. This research is expected to be used as a reference by the government to make regulations, plans, and strategies related to hazardous waste management to prevent harm to the environment and human health.

ЦИФРОВІ РІШЕННЯ В УПРАВЛІННІ ЕЛЕКТРОННИМИ ВІДХОДАМИ

The article is devoted to the actual problem of substantiating directions for the use of innovative digital solutions in the management of waste electrical and electronic equipment. The structure of e-waste in developed countries in 2022, which includes IT and telecommunications devices, consumer devices and solar panels, power tools and medical devices, was analyzed and it was found that the largest share is household large-sized appliances (52.7%). Analysis of the dynamics of electronic waste generation per capita in industrialized countries in 2013–2022 showed that in 2022, each resident of Australia – 22.42 kg, Canada – 20.58 kg, Israel – 14.56 kg of electronic waste was generated, Japan – 20.55 kg, Korea – 16.80 kg, Great Britain – 24.63 kg, USA – 21.50 kg, EU – 28.54 kg. Considered the practice of waste management in industrially developed countries. For example, Japan (18–25%) is most actively involved in the processing of electronic waste. The EU has developed a strategy - an action plan for the closed cycle economy, in which the reduction of electrical and electronic waste is a key priority, and a number of proposals have been submitted to promote the repair of goods. The well-founded role of digitalization in the management of electronic waste, which consists in increasing the speed of waste processing and increasing its economic efficiency. The areas of use of innovative digital solutions in electronic waste management are defined, such as: robotics, artificial intelligence and neural networks, the Internet of Things, cloud solutions and data analytics. The advantages of digitization in waste management are disclosed, which includes: automation in waste disposal; improvement of the recycling process; ensuring waste minimization and saving natural resources; creating opportunities to identify problem areas and assess the efficiency of electronic waste disposal; helps to save money, energy and time for waste collection and disposal. The directions for handling electrical and electronic equipment waste have been defined, which consist in preventing the generation of waste, its collection, separation, processing, extraction of secondary raw materials through reuse, recycling and other forms of recovery, which will contribute to the realization of the goals of sustainable production and consumption and the improvement of environmental indicators.

Green cryptocurrencies and portfolio diversification in the era of greener paths

The shift towards cleaner fuels from hydrocarbons has influenced nearly all market types and asset classes, and cryptocurrencies are no exception. The complex mechanism of blockchain and mining consumes high levels of electricity and surges environmental footprints in electronic waste generation. Existing studies that examine green and sustainable investments are limited to sustainable equities or green bonds; therefore, this study opens up a new research direction by considering green (energy-efficient) cryptocurrencies. First, this study develops a four-step screening process to systematically select cryptocurrencies that are greener than others. A comprehensive set of green and non-green assets and a battery of empirical tests are then employed to examine the diversification benefits of selected green cryptocurrencies against several well-diversified equity portfolios at the global, regional, and country levels. The diversification benefits of green cryptocurrencies are compared with non-green cryptocurrencies using (i) the four-moment modified value at risk and conditional value at risk, (ii) four different portfolio optimization strategies, and (iii) dynamic correlation-based hedge and safe-haven regression analyses. The results show that green cryptocurrencies provide diversification benefits that are at least comparable to, and in some cases, superior to, non-green (energy-intensive) cryptocurrencies. Cardano and Tezos are identified as green cryptocurrencies offering the most diversification benefits to investors, followed by EOS, Steller, and IOTA. This study provides valuable insights to investors and policymakers, specifically those concerned with achieving sustainability and ESG-compliance (environmental-social-governance) goals and seeking green assets to hedge and diversify various traditional investments.

Achieving ultrasensitivity and high breathability in biodegradable piezoresistive electronic skins

Nonbiodegradable components, such as synthetic polymers, have been widely used in the fabrication of flexible piezoresistive sensors and electronic skins (e-skins), resulting in the generation of electronic waste (e-waste) and toxic by-products. To overcome this issue, a wide range of biodegradable natural biopolymers and synthetic polymers have been employed. However, most of the current biodegradable e-skins demonstrate limitations such as low sensitivity, poor electrical conductivity, limited breathability, and low stability. To address these limitations, this study proposes a highly breathable and ultrasensitive piezoresistive e-skin based on the oxidized single-walled carbon nanotube (Ox-SWCNT)/silver nanowire (AgNW)-coated leaf skeletons. The developed disposable piezoresistive e-skin exhibits a remarkable performance including high sensitivity (19.75 ± 1.5 kPa−1, <3 kPa), sensing range of ≤42 kPa, ultralow limit of detection (∼0.27 Pa), linearity for low- and high-pressure regimes, high flexibility, high stability (3000 cycles), low weight, ultrahigh breathability, and biodegradability. In addition, the developed leaf-based e-skin demonstrates outstanding sensing performance in human-motion monitoring by detecting various motions such as subtle and vigorous flexions, airflow, and vocal-cord vibrations. The proposed piezoresistive e-skin is a promising platform for the development of various low-cost, biocompatible, fully biodegradable, and point-of-care (POC) e-skins for a wide range of subtle and vigorous pressure-monitoring applications including human–machine interfaces (HMIs), robotics, prosthesis, and flexible electronics.

Knowledge, attitude, practice, and generation of electronic waste (e-waste) among students of health sciences in a private college in Pune

Background: In "the era of information," e-waste is a major threat to solid waste management and public health. E-waste contains dangerous and destructive compounds that may affect the environment and human health if not properly handled. The objective of the study was to assess the knowledge, attitude, practice on e-waste and to determine e-waste generation rates for two electronic products: computers and cell (mobile) phones among health science students of the Symbiosis Institute of Health Sciences, Pune. Methodology: A web-based and institution-based cross-sectional study of students pursuing different health science courses was conducted. Out of 680 students, 405 were randomly selected, dispersed in six strata, and the Google questionnaire was disseminated using a proportionate probability to size ratio, with 188 participants responding at a 46.41% response rate. Results: Out of 188 respondents, 95 (50.6%) and 77 (41.2%) study subjects knew about the health and environmental risks associated with e-waste. Physical damage caused 126 (67%) of the research participants to replace their electronics. 67% would learn about e-waste management if it were on the course. 66% purchase 1-3 electronics devices every year, while 23% purchase 4-6. Overall e-waste generation rates among the participants were 0.223 units/capita/year for computers and 0.42 units/capita/year for mobile phones. Conclusion: This research reveals a lack of understanding and behaviours related to e-waste among students of health sciences, highlighting the need for health education on e-waste for public health and awareness on safe e-waste disposal, both of which are critical for a risk-free future.

Measuring and Indexing the Durability of Electrical and Electronic Equipment

Due to the large and unsustainable use of valuable natural resources and electronic waste generation worldwide, which poses risks to human health and the environment, different organizations have initiated efforts to shift from a linear economy to a circular economy. A crucial aspect of promoting a circular economy is improving product durability, which can reduce resource extraction and waste because products remain in use for a longer period. Methods for measuring and indexing durability should encourage consumers to buy more durable products and incentivize manufacturers to compete in improving durability. This paper reviews past research on measuring product durability. It proposes an overall framework based on the promise of product life as well as its readiness to perform required functions for indexing durability. Finally, it presents an example of durability assessment. The proposed framework enables manufacturers to improve the design and communication of product durability. Furthermore, it supports establishing durability standards by standard development organizations and promotes sustainability through durability initiatives.

Transforming E-Waste into Opportunities: Driving Organizational Actions to Achieve Sustainable Development Goals

With technological advancements, there has been a significant increase in the generation of electronic waste (e-waste), leading to severe environmental consequences. Inadequate e-waste management poses obstacles to achieving the Sustainable Development Goals (SDGs) and results in detrimental effects such as pollution, health risks, and resource depletion. Recycling and reusing are vital due to the presence of toxic and valuable elements in e-waste. However, several barriers impede effective management, including limited collection points, insufficient awareness, and inadequate policies. For this reason, this paper aims to propose drivers for developing and improving organizational actions that enhance e-waste management, enabling companies to contribute to the achievement of the SDGs. Content analysis was employed as the research method to identify booster elements and systematize e-waste management drivers. Thirty-six booster elements related to SDGs 3, 6, 7, 8, 9, 11, 12, and 17 were identified based on 30 relevant scientific articles from Scopus and 16 sustainability reports from well-ranked companies on the New York Stock Exchange. The systematized drivers encompass recycling and treatment techniques, sustainable manufacturing and consumption, e-waste management technologies, and cooperation networks. The scientific contribution of this work lies in incorporating empirical elements into the literature and enriching the theory of sustainable practices in the electronic equipment industry. In an applied manner, this article contributes to managers who can use the proposed drivers to improve the management of e-waste, thus reducing costs and enhancing the socio-environmental performance of their companies.

Electrohydrodynamic Printed PEDOT:PSS/Graphene/PVA Circuits for Sustainable and Foldable Electronics

AbstractThe generation of electronic waste (e‐waste) poses a significant environmental challenge, necessitating strategies to extend electronics’ lifespan and incorporate eco‐friendly materials to enable their rapid degradation after disposal. Foldable electronics utilizing eco‐friendly materials offer enhanced durability during operation and degradability at the end of their life cycle. However, ensuring robust physical adhesion between electrodes/circuits and substrates during the folding process remains a challenge, leading to interface delamination and electronic failure. In this study, electrohydrodynamic (EHD) printing is employed as a cost‐effective method to fabricate the eco‐friendly foldable electronics by printing PEDOT:PSS/graphene composite circuits onto polyvinyl alcohol (PVA) films. The morphology and electrical properties of the printed patterns using inks with varying graphene and PEDOT:PSS weight ratios under different printing conditions are investigated. The foldability of the printed electronics is demonstrated, showing minimal resistance variation and stable electronic response even after four folds (16 layers) and hundreds of folding and unfolding cycles. Additionally, the application of printed PEDOT:PSS/graphene circuit is presented as a resistive temperature sensor for monitoring body temperature and respiration behavior. Furthermore, the transient features and degradation of the PEDOT:PSS/graphene/PVA based foldable electronics are explored, highlighting the potential promise as transient electronics in reducing electronic waste.

A Fully Biodegradable and Biocompatible Ionotronic Skin for Transient Electronics

AbstractWearable electronics have impacted many aspects of human life including health monitoring, disease diagnosis, and human‐machine interfacing. However, the rapid development also accelerates the generation of electronic waste (e‐waste), which is threatening the health of ecological systems. Accordingly, high‐performance biodegradable materials suitable for transient electronics are highly demanded and challenging. In this work, a fully biodegradable and biocompatible ionotronic skin is designed based on double‐network natural polyelectrolytes derivatives. It consists of carboxylated chitosan (CCS) and sulfobetaine methacrylate (SBMA) polymerized in glycerol and water followed by cross‐linking with hydrogen bonds and electrostatic attraction (namely SBMAX‐CCSY‐Glyz). By macromolecular engineering, the ionotronic skin exhibits high ionic conductivity, good compliance with skin, as well as complete degradability, which is capable of transient measurement of electrophysiology. Applied on the sciatic nerve of bullfrog, it can accurately record action potentials and fully degrade in only 3 days without any residue. Such biodegradable and biocompatible ionotronic skin will shed light on the design of ionotronic materials for future transient electronics.

Electronic waste (E-waste) generation and management scenario of India, and ARIMA forecasting of E-waste processing capacity of Maharashtra state till 2030

This article addresses a critical environmental issue largely attributed to Gen-Z, namely Electronic waste (E-waste). The modern human lifestyle has significantly impacted waste management, with new technological advancements posing both environmental challenges and economic opportunities. E-waste, generated due to the disposal or end-of-life of electronic products, is now one of the fastest-growing domestic waste streams. Proper E-waste management and monitoring are essential for achieving maximum resource utilization and reducing the adverse impacts of E-waste, in line with the Sustainable Development Goals. India has laws and legislation in place to ensure the safe handling, management, and treatment of E-waste, with the pollution control board serving as the monitoring and tracking authority. This study focuses on the state of Maharashtra, investigating past and future trends using Auto Regressive Integrated Moving Average (ARIMA) models, commonly used in time series analysis and forecasting. The study predicts that the average E-waste processing capacity (recycling/dismantling) from 2023–2030 will be 163563.15 MT (metric tons), with forecasted values increasing steadily over the years, reaching 248 recyclers by the year 2030. By analysing rate of change in E-waste processing capacity from 2023–2030, there will be chances of 6.86 % annually. This is also highlighting the scope of entrepreneurship in E-waste recycling industries by detecting average expansion of recyclers by 7.23 % per year. The study emphasizes the significant role of policy and decision-making in managing this rapidly growing waste stream from an environmental management and circular economic perspective.

Inventory analysis of potential electronic waste generation in Setu, Tangerang Selatan

Electronic waste (E-waste) is currently one of the waste streams with the most significant growth rate due to the incredible technological advancement and greater use of information and telecommunications (IT) technologies. One of the main concerns regarding environmental contamination that people worldwide have is the management of electronic waste. This problem is due to the quickly rising use of technological devices. As a result, electrical and electronic equipment has a finite shelf life and eventually becomes outdated. Lack of knowledge regarding the amount of waste produced and the transit of materials is one of the problems Indonesian governments have while handling e-waste. This study aimed to outline the possibilities of producing electronic waste in Setu, Tangerang Selatan. Online surveys of respondents from households were used as the methodology, but just for appliances like refrigerators, air conditioners, televisions, laptops, and mobile phones. Since this problem becomes one of the most challenging parts of gaining the closest data to the actual waste stream, it is thought that this method is an effective way to gather the vast amounts of data required for the government to establish related policies. Fifty-two residences in Setu District, Tangerang Selatan City, were surveyed using a modified UNEP questionnaire. The study’s findings revealed that in terms of quantity-78 units produced as opposed to 244 units of the products listed-mobile phones are the most frequently produced electronic waste. Meanwhile, the refrigerator accounts for the most significant percentage of e-waste in terms of weight, or 40.93%. The findings of this study help policymakers create a formal e-waste management system by allowing them to calculate the amount of e-waste generated in Setu, Tangerang Selatan. Additionally, the approach used can be a valuable, user-friendly tool to produce the closest actual data that are typically required by the Ministry of Environment and Forestry, such as to develop a database that becomes a part of Sistem Informasi Pengelolaan Sampah Nasional (SIPSN) or National Waste Management Information System.

Female Directors, Sustainability Steering Committee and E-Waste Information Disclosure in Malaysian Technology and Telecommunication Industries

The digitalisation era has brought an environmental issue regarding the generation of electrical and electronic waste (e-waste). The global scenario has started questioning how these appliances are taken care of when they reach the end of their useful lives. The advent of these obsolete appliances has created a catastrophe for the health of humans and the environment. Furthermore, business firms in telecommunication and technology industries face the pressure to engage in more severe action towards e-waste management and to report the activities in the annual reports due to their activities which are highly related to the generation of e-waste. In addressing this issue, the study intends to examine the e-waste information disclosure by firms in the two industries. In addition, the study also investigates if the e-waste information disclosure would differ between firms with more female directors and with a sustainability steering committee compared to their counterparts. This study hypothesises that firms with high female directors and a sustainability steering committee will show significantly higher e-waste information disclosure by utilising the virtue ethics theory. Fifty-nine companies of Bursa Malaysia listed firms in the technology and telecommunication industries were taken as samples. The results were consistent with the hypotheses, where firms with a high proportion of female directors and firms with a sustainability steering committee exhibit significantly high e-waste information disclosure compared to their counterparts. The results from this study may give some insights into how business firms address their e-waste management issue and can be significant in achieving the Sustainable Development Goals (SDGs).

A Comprehensive Review on E-Waste Management Strategies and Prediction Methods: A Saudi Arabia Perspective

Electronic waste generation is increasing dramatically throughout the world. Consequently, this increase in E-waste harms the environment, health, and other aspects of human life. Moreover, hazardous substances and the informal disposal of E-waste severely threaten human health and the environment. Saudi Arabia is the largest Arab country in terms of electronic waste generation and is the Arab country that generates the most E-waste. Over the past few decades, several initiatives and policy implementations have been undertaken in the country. However, the management of E-waste is still a source of distress and an unresolved issue. Sustainable development requires much more effort, primarily efficient E-waste management, which can only be achieved by establishing a formal collection system, early forecasting, and accurate estimations. The purpose of this study is to provide an overview of the fundamental and emerging trends in E-waste production worldwide and in Saudi Arabia. This paper aims to summarize the hazardous elements present in E-waste, their dangerous effects, and the economic potential for recycling E-waste as a means of developing sustainable communities. This study explores the practices regarding efficient E-waste management and E-waste estimation and prediction globally, specifically in Saudi Arabia and other Arab countries. This study suggests that more than the use of a single management probe will be needed to achieve significant results. Instead, a complementary approach can be used to achieve the most effective results. Additionally, people should be aware of the importance of handling and recycling E-waste. This study emphasizes the importance of formal collection and documentation to ensure effective monitoring and sustainable development in any developed country.

Super-Flexible, Transparent Synaptic Transistors Based on Pullulan for Neuromorphic Electronics

With the development of artificial intelligence, super-flexibility and transparent neuromorphic electronics are gradually showing high application value in the fields of wearable see-through electronics and biomedical applications. However, it is still a huge problem to realize synaptic devices with super-flexibility and transparent characteristics. Here, an organic synaptic transistor (OST) based on natural pullulan is fabricated with super-flexibility and high transmittance (~83.3%), which enables it to achieve conformal and non-destructive attachment to arbitrary-shaped objects without affecting viewing. Various synaptic behaviors are successfully simulated even under extreme bending, showing outstanding mechanical stability. Moreover, our OSTs can achieve ultrarapid degradation in ambient water, which will reduce the generation of electronic waste. This work provides a guide for the development of super-flexible and transparent neuromorphic electrons, demonstrating a great step toward next-generation artificial intelligence.

A Critical Review on the Recovery of Base and Critical Elements from Electronic Waste-Contaminated Streams Using Microbial Biotechnology.

Pollution by end-of-life electronics is a rapid ever-increasing threat and is a universal concern with production of million metric tons of these wastes per annum. Electronic wastes (E-waste) are rejected electric or electronic equipment which have no other applications. The aggrandized unproper land filling of E-waste may generate hazardous effects on living organisms and ecosystem. At present, millions of tons of E-waste await the advancement of more efficient and worthwhile recycling techniques. Recovery of base and critical elements from electronic scraps will not only reduce the mining of these elements from natural resources but also reduces the contamination caused by the hazardous chemicals (mostly organic micropollutants) released from these wastes when unproperly disposed of. Bioleaching is reported to be the most eco-friendly process for metal recycling from spent electronic goods. A detailed investigation of microbial biodiversity and a molecular understanding of the metabolic pathways of bioleaching microorganisms will play a vital function in extraction of valuable minerals from the end-of-life scraps. Bioleaching technique as an economic and green technology costs around 7 USD per kg for effective reusing of E-waste as compared to other physical and chemical techniques. This review provides a summary of worldwide scenario of electronic pollutants; generation, composition and hazardous components of electronic waste; recycling of valuable elements through bioleaching; mechanism of bioleaching; microorganisms involved in base and critical element recovery from E-waste; commercial bioleaching operations; and upcoming aspects of this eco-friendly technique.

Introducing heterotrophic iron ore bacteria as new candidates in promoting the recovery of e-waste strategic metals.

Electrical instruments are an integral part of human life resulting in a vast electronic waste generation (74.7 Mt by 2030), threatening human life and the environment due to its hazardous nature. Therefore, proper e-waste management is a necessity. Currently, bio-metallurgy is a sustainable process and an emerging research field. Simultaneous leaching of metals using two groups of indigenous heterotrophs and autotrophs was an exciting work done in this study. Bioleaching experiments using pre-adapted cultures were investigated at three e-waste densities: 5, 10, and 15g/L. Statistical analysis was done using two-way ANOVA. Copper (93%), zinc (21.5%), and nickel (10.5%) had the highest recovery efficiencies. There was a significant difference between copper, nickel, tin, and zinc concentrations and the bacterial group (P < 0.05); Iron-oxidizing bacteria showed the most weight decrease and recovered 46-47% of total metals, mainly copper and nickel, while sulfur oxidizers were more capable of zinc leaching. The heterotrophs solubilized tin preferably and substantially decreased e-waste weight. Using heterotrophs alongside autotrophs is proposed to promote metal recovery.

A sustainable route for the recovery of metals from waste printed circuit boards using methanesulfonic acid

The rapid increase in electronic waste (e-waste) generation and its unsustainable management pose a threat to the environment and human well-being. However, various valuable metals are present in e-waste, which makes it a potential secondary source to recover metals. Therefore, in the present study, efforts were made to recover valuable metals (Cu, Zn, and Ni) from waste printed circuit boards (WPCB) of computers using methanesulfonic acid (MSA). MSA is contemplated as a biodegradable green solvent and has a high solubility for various metals. The effect of various process parameters (MSA concentration, H2O2 concentration, stirring speed, liquid to solid ratio, time, and temperature) was investigated on metal extraction to optimize the process. At the optimized process conditions, 100% extraction of Cu and Zn was achieved, while Ni extraction was around 90%. The kinetic study for metal extraction was performed using a shrinking core model and findings showed that MSA-aided metal extraction is a diffusion-controlled process. Activation energies were found to be 9.35, 10.89, and 18.86 kJ/mol for Cu, Zn, and Ni extraction, respectively. Furthermore, the individual recovery of Cu and Zn was achieved using the combination of cementation and electrowinning, which resulted in 99.9% purity of Cu and Zn. The current study proposes a sustainable solution for the selective recovery of Cu and Zn from WPCB.