In the last few decades, the rapid technological evolution has led to a growing generation of waste electrical and electronic equipment (WEEE). Not rarely, it has been exported from industrialized to developing countries, where it represents a secondary source of valuable materials such as gold, copper, and silver. The recycling of WEEE is often carried out without any environmental and health protection. This paper reviews recent literature dealing with the informal treatment of WEEE in developing regions, gathering and analyzing data on concentration of both inorganic and organic pollutants in the environment. Open burning practices are revealed as most polluting ‘technology’, followed by mechanical treatment and leaching. Significant levels of pollutants have been detected in human bodies, both children and adults, working in or living in areas with informal WEEE treatment.

Waste plastic today is a global threat. The rapid increase in global production and use has led to increasing quantities of plastics in industrial and municipal waste streams. While in industrialized countries plastic waste is taken up by a waste management system and at least partly recycled, in low-income countries adequate infrastructure to collect and treat waste adequately is often not in place. This paper analyzes how plastic waste is handled in Vietnam, a country with a fast-growing industry and growing consumption. The recycling of plastic waste typically takes place in an informal context. To demonstrate this in more detail, two rural settlements—so-called craft villages—are taken as case studies. Technologies and processes for plastic recycling are described and related risks for human health and the environment are shown, as well as the potential for the improvement of this situation.

Plastics are a ubiquitous material with good mechanical, chemical and thermal properties, and are used in all industrial sectors. Large quantities, widespread use, and insufficient management of plastic wastes lead to low recycling rates. The key challenge in recycling plastic waste is achieving a higher degree of homogeneity between the different polymer material streams. Modern waste sorting plants use automated sensor-based sorting systems capable to sort out commodity plastics, while many engineering plastics, such as polyoxymethylene (POM), will end up in mixed waste streams and are therefore not recycled. A novel approach to increasing recycling rates is tracer-based sorting (TBS), which uses a traceable plastic additive or marker that enables or enhances polymer type identification based on the tracer’s unique fingerprint (e.g., fluorescence). With future TBS applications in mind, we have summarized the literature and assessed TBS techniques and spectroscopic detection methods. Furthermore, a comprehensive list of potential tracer substances suitable for thermoplastics was derived from the literature. We also derived a set of criteria to select the most promising tracer candidates (3 out of 80) based on their material properties, toxicity profiles, and detectability that could be applied to enable the circularity of, for example, POM or other thermoplastics.

With the rise of electric vehicles (EVs) and thus lithium‐ion batteries (LIBs), the number of end‐of‐life (EoL) LIBs after their first life in EVs is about to increase significantly. These end‐of‐first‐life (EoFL) EV LIBs still have sufficient energy density for less‐demanding second‐life applications like stationary battery energy storage systems (BESSs) or mobile applications (e.g., forklifts, tools). Repurposing EoFL EV LIBs extends their lifespan, offering sustainability benefits and supporting several United Nations (UN) Sustainable Development Goals (SDGs). However, prevailing market entry barriers, such as high repurposing costs, little information on battery history and aging, or lacking performance indicators, hinder the widespread implementation of second‐life applications. Thus, this study aims to identify preconditions for considering and selecting useful EoFL LIBs and to determine key performance indicators (KPIs) to minimize economic risks for a successful second‐life market launch. KPIs were rated according to importance using a Likert scale, and reference values were introduced. A mixed‐methods approach, using expert interviews, an exploratory workshop, and an online survey, was applied. Twelve important preconditions were identified, with the “availability of information on battery specification” and “compliance with standards and regulations” considered very important. In addition, 12 KPIs were derived, covering six economic, three environmental, and three technical and safety‐related indicators. The KPIs “state of safety (SoS)” and “resource savings (R_sav)” were rated as highly important. Overall, the findings provide performance measurement guidance for repurposing companies, facilitating the market launch and adoption of second‐life applications. Future research can build on these results and investigate variations among different battery types, ultimately promoting a circular economy.

Engineering plastics, such as polyoxymethylene (POM), are high-performance thermoplastics designed to withstand high temperature or mechanical stress and are used in electronic equipment, the automotive industry, construction, or specific household utensils. POM is immiscible with other plastics but due to a low volume of production, no methods were developed to separate it from the residual plastic waste stream. Therefore, POM recycling is minimal despite its high market value. This paper provides a proof of concept for tracer-based sorting (TBS) as a potential solution for increasing the separation efficiency of low-volume, high-quality polymers. For this purpose, yttrium oxide (Y₂O₃) and cerium (IV) oxide (CeO₂) have been embedded into the POM matrix. Mechanical tests of samples at varying concentrations (0.1 to 1000 ppm) of both tracers were conducted, followed by an analysis of detectability and dispersibility using a portable X-ray fluorescence spectrometer (p-XRF), subsequently optimizing detection time and tracer concentration. Finally, an experimental scenario was developed to test the fate and potential recovery of the tracer material after the thermal treatment of plastics. A low detectable concentration, short measurement time, low influence on mechanical parameters of the compound, and low loss ratio after simulated recycling prove Y₂O₃ to be a suitable tracer for the industrial implementation of TBS.

Zusammenfassung Im Vergleich zu Metallerzen der Erdkruste sind Metalle in Elektro- und Elektronikaltgeräten (EAGs) in deutlich höheren Konzentrationen vorhanden, sind aber häufig in komplexe Matrizen unterschiedlicher Metalle oder in Nichtmetall-Metall-Komplexe eingebunden. Aufgrund der komplexen Materialzusammensetzung von EAGs, die v. a. durch eine Vielzahl von am Markt verfügbaren Gerätetypen und rasche Technologieentwicklung bedingt ist, wird das volle Recyclingpotenzial derzeit bei weitem noch nicht ausgeschöpft. Davon sind besonders edle und kritische Metalle betroffen, die trotz umfassender Recyclingprozesse mit sehr geringer Effizienz zurückgewonnen werden. Die Erhöhung der Rückgewinnungsrate dieser Metalle erfordert effizientere Methoden und Verfahren. Daraus resultiert der Bedarf an besseren Datengrundlagen zur Charakterisierung von EAGs. Im Rahmen dieser Forschungsarbeit wurden besonders wertvolle Bauteile aus EAGs durch eine Tiefenzerlegung und anschließend mit einer Reihe von einfachen Methoden analysiert, wie z. B. Nickeltest, Aluminium/Magnesium-Test, um einen möglichst praktikablen Ansatz für die Materialanalyse von EAGs bereitzustellen. Die vorgestellten Ergebnisse basieren einerseits auf Literaturrecherchen, anderseits auf den Ergebnissen der durchgeführten Versuche zur Bestimmung der Materialzusammensetzung von EAGs. Dadurch ist es möglich, die besonders wertvollen Typen von EAGs bzw. deren Bauteile in Bezug auf edle und kritische Metalle zu bestimmen. Anschließend werden neben dem Materialgehaltpotenzial auch die Herausforderungen und Potenziale für die Bestimmung der Materialzusammensetzung von EAGs diskutiert.