As the accumulation of waste from solar panels and solar scraps rapidly increases, recycling these materials has become increasingly critical. Unfortunately, the complexity of disassembling solar ...panels often renders the recycling process unprofitable due to the low value of the recovered products, resulting in high service fees. Although numerous studies have sought to simplify the disassembly process and enhance the purity of the recovered products, these solutions often involve costly, toxic, and complex methods. In response, we introduce an innovative green recycling technique using a straightforward alkaline leaching process. This method allows for efficient recycling and refining of solar cells, yielding high-purity SiO2 (99.994 %) at a recycling rate of 92.74 % and generating green hydrogen. A preliminary cost analysis indicates that this process holds substantial commercial potential and high profitability. The proposed technique offers a new pathway towards making renewable energy sources more sustainable and economically feasible.
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The rapid proliferation of electric vehicles equipped with lithium‐ion batteries (LIBs) presents serious waste management challenges and environmental hazards for recyclers after scrap. Closed‐loop ...recycling contributes to the sustainable development of batteries and plays an important role in mitigating raw material shortages and supply chain risks. Herein, current direct cathode regeneration methods for industrialized recycling are outlined and evaluated. Different regeneration methods for spent cathode materials are summarized, which provide a new perspective for realizing closed‐loop recycling of LIBs. A reference recycling route for retrofitting existing cathode production lines is proposed and minimizes the costs. In addition to promoting the industrialization of direct cathode recycling, the environmental, economic, and political benefits of battery recycling are also highlighted.
Direct cathode regeneration methods are summarized to highlight the technical challenges, current status, supply chain, carbon footprints, and possible solutions for closed‐loop battery recycling. The environmental, economic, and political benefits of the direct cathode regeneration methods are also considered, and a reference recycling route with available automated recycling technology is proposed and minimizes the costs.
With increasing usage of polyethylene terephthalate (PET) wastes polluting the oceans and environment, the recycling of PET wastes has become a crucial issue to be overcome. In this article, a review ...of the different technologies that have been developed to recycle PET wastes and common routes for recycled PET (rPET) is presented. The impacts of varied recycling technologies on the properties of rPET are also discussed herein. The review also focuses on the recovered products by each of the technology and their uses that have been reincorporated into new applications for example, from plastic bottle wastes to 3D scaffolds for biomedical application. Different recycling technologies such as reactive extrusion, chemical recycling and dissolution/precipitation exhibit specific properties due to the influence of the different concepts from one technology to another. A new trend called electrospinning of rPET to produce nanofibers has also garnered attention to be used for different applications. This article will first introduce the recycling technologies concept, and then the properties of the recovered product will be discussed and finally, we will focus on the applications of rPET produced from each of the technologies in various fields such as construction, textile, filtration, and biomedical applications.
Polyethylene terephthalate (PET) is completely recyclable and among the most recycled plastic globally. Recycling of PET can be done through various ways including mechanical recycling such as reactive extrusion and also by chemical means which transforms the PET into its monomers or various valuable chemicals. Other recycling technologies include dissolution/precipitation as well as blending and compatibilization. Once PET has been recycled, it is known as recycled PET (rPET) and can be used in various applications such as construction and textile. Another route that is gaining massive attention for rPET is the fabrication of rPET fibrous membranes by electrospinning. These elctrospun rPET fibers provide more possibilities for engineered application of rPET such as air and water filtration purposes.
Closed‐loop recycling of polymers represents the key technology to convert plastic waste in a sustainable fashion. Efficient chemical recycling and upcycling strategies are thus highly sought‐after ...to establish a circular plastic economy. Here, we present the selective chemical depolymerization of polycarbonate by employing a vanillin derivative as bio‐based feedstock. The resulting di‐vanillin carbonate monomer was used in combination with various amines to construct a library of reprocessable poly(imine‐carbonate)s, which show tailor‐made thermal and mechanical properties. These novel poly(imine‐carbonate)s exhibit excellent recyclability under acidic and energy‐efficient conditions. This allows the recovery of monomers in high yields and purity for immediate reuse, even when mixed with various commodity plastics. This work provides exciting new insights in the design of bio‐based circular polymers produced by upcycling of plastic waste with minimal environmental impact.
Upcycling of polycarbonate (BPA‐PC) with a bio‐based vanillin derivative into novel dialdehyde monomer DVEC is shown. DVEC was further polymerized by using primary amines into high‐performance poly(imine‐carbonate)s. These modular polymers are reprocessable and chemically recyclable under acidic and energy‐efficient conditions, thereby enabling a closed‐loop recycling scheme.
The current global plastics economy is highly linear, with the exceptional performance and low carbon footprint of polymeric materials at odds with dramatic increases in plastic waste. Transitioning ...to a circular economy that retains plastic in its highest value condition is essential to reduce environmental impacts, promoting reduction, reuse, and recycling. Mechanical recycling is an essential tool in an environmentally and economically sustainable economy of plastics, but current mechanical recycling processes are limited by cost, degradation of mechanical properties, and inconsistent quality products. This review covers the current methods and challenges for the mechanical recycling of the five main packaging plastics: poly(ethylene terephthalate), polyethylene, polypropylene, polystyrene, and poly(vinyl chloride) through the lens of a circular economy. Their reprocessing induced degradation mechanisms are introduced and strategies to improve their recycling are discussed. Additionally, this review briefly examines approaches to improve polymer blending in mixed plastic waste streams and applications of lower quality recyclate.
Degradation during mechanical recycling remains the largest barrier to efficient recycling. This review presents innovations in plasticizers, fillers, stabilizers, chain extenders, and blending technologies to reverse extrusion‐induced degradation for packaging polymers. Secondary uses of lower quality recyclates are also briefly discussed in order to curb land‐fill.
What Do We Know About Metal Recycling Rates? Graedel, T. E.; Allwood, Julian; Birat, Jean-Pierre ...
Journal of industrial ecology,
June 2011, Volume:
15, Issue:
3
Journal Article
Peer reviewed
Open access
Summary
The recycling of metals is widely viewed as a fruitful sustainability strategy, but little information is available on the degree to which recycling is actually taking place. This article ...provides an overview on the current knowledge of recycling rates for 60 metals. We propose various recycling metrics, discuss relevant aspects of recycling processes, and present current estimates on global end‐of‐life recycling rates (EOL‐RR; i.e., the percentage of a metal in discards that is actually recycled), recycled content (RC), and old scrap ratios (OSRs; i.e., the share of old scrap in the total scrap flow). Because of increases in metal use over time and long metal in‐use lifetimes, many RC values are low and will remain so for the foreseeable future. Because of relatively low efficiencies in the collection and processing of most discarded products, inherent limitations in recycling processes, and the fact that primary material is often relatively abundant and low‐cost (which thereby keeps down the price of scrap), many EOL‐RRs are very low: Only for 18 metals (silver, aluminum, gold, cobalt, chromium, copper, iron, manganese, niobium, nickel, lead, palladium, platinum, rhenium, rhodium, tin, titanium, and zinc) is the EOL‐RR above 50% at present. Only for niobium, lead, and ruthenium is the RC above 50%, although 16 metals are in the 25% to 50% range. Thirteen metals have an OSR greater than 50%. These estimates may be used in considerations of whether recycling efficiencies can be improved; which metric could best encourage improved effectiveness in recycling; and an improved understanding of the dependence of recycling on economics, technology, and other factors.
•Investigation of optimal timing of pricing in a dual-channel reverse supply chain.•Consideration of a supply chain consisting of a recycling company and a collector.•We have the following two major ...findings.•There is a first-mover advantage to acquisition price announcement.•The company should announce the online price before announcing the transfer price.
The rapid development of information technologies enables recycling companies to purchase and collect used products from consumers through both traditional and Internet-based online channels. Because an online channel transmits price information instantly to consumers, choosing the best time to announce the recycling price (i.e., acquisition price) of used products to consumers has become a critical problem for recycling companies. This paper seeks to solve this problem by developing a game-theoretic model describing a dual-channel reverse supply chain consisting of a recycling company and a third-party collector in which the recycling company purchases products not only through a third-party collector, but also directly from consumers online. We derive two major results by solving the model. The first is that first-mover advantage arises, which indicates that each firm constituting a dual-channel reverse supply chain should announce its own recycling price before the other. This first result is notable because it is exactly opposite to conventional wisdom that the second-mover advantage of pricing usually emerges when price competition occurs among firms in a horizontal relationship, which is well known in noncooperative game theory. The second result is that the recycling company can maximize its own profit and consumers' surplus by announcing its recycling price in the online channel before or upon, but not after, determining the transfer price paid to the collector for products collected in the offline channel. Both results can be used as practical decision-making guidelines in dual-recycling channel reverse supply chain management.
•3 out of 9 chemical recycling technologies have the highest TRL of 9.•Plasma gasification of plastics could soon be fully commercialized.•Economic feasibility of chemical recycling is still ...challenging to asses.•Chemical recycling is only a part of solution for plastic recovery.
Chemical recycling is considered an attractive technological pathway for reducing waste and greenhouse gas emissions, as well as promoting circular economy. In the EU, readiness to develop a full commercial plant is becoming increasingly important given the ambitious goal to recycle all plastics by 2030. Household packaging streams tend to be of lower quality and lower recycling performance compared to industrial and commercial waste streams, thus requiring particular attention. This paper assesses chemical recycling technologies available and identifies the most suitable for recycling of household plastic waste. We identify eight different technologies and compare them in terms of process temperature, sensitivity to feedstock contamination and level of polymer breakdown, three critical factors affecting the cost and attractiveness of a chemical process. In addition, we carry out a Technology Readiness Level (TRL) assessment for eight technologies based on the stage of their present development. The review is based on peer-reviewed scientific papers and information collected from technology developers and providers, as well as interviews with experts. Our analysis outlines advantages and disadvantages of technologies available for chemical plastic recycling and their TRL. The chemical recycling technologies with the highest TRL are pyrolysis, catalytic cracking and conventional gasification. However, the economic feasibility of these technologies is difficult to assess due to the low number of projects in operation and scarcity of data available for comparison. The results of this analysis provide timely information as policy makers and developers set targets for recycling, and contemplate investments on research and chemical plastic recovering plants.
The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, ...dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling.
Recycling is a cornerstone of waste management. Despite its significance and growing interest, the US recycling rate has stagnated at around 35% for more than the past decade. In this study, we ...investigate an effective waste collection method as well as factors that may negatively affect recycling program management as a proxy measure of the recycling rate. To this end, recycling program managers and coordinators were surveyed since they play a pivotal role in the flow of recyclable materials. We found a combination of curbside and drop-off recycling to be the most cost-effective, but when managers’ experience level is factored in, the perceived significance of the combination approach decreases. Concerning barriers to recycling, we found that market variability for recycled materials, insufficient public participation in waste collection, and knowledge of best practices are critical inhibiting factors. In addition, China’s complete ban on waste import by 2030, an organizational framing effect of recycling, and a strong need for public education and outreach activities about recycling have emerged as new problems for recycling. Our findings point out recycling systems that reduce those setbacks to improve recycling performance and increase the recycling rate.
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