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The growing textile industry is polluting the environment and producing waste at an alarming rate. The wasteful consumption of fast fashion has made the problem worse. The waste management of textiles has been ineffective. Spurred by the urgency of reducing the environmental footprint of textiles, this review examines advances and challenges to separate important textile constituents such as cotton (which is mostly cellulose), polyester (polyethylene terephthalate), and elastane, also known as spandex (polyurethane), from blended textiles. Once separated, the individual fiber types can meet the demand for sustainable strategies in textile recycling. The concepts of mechanical, chemical, and biological recycling of textiles are introduced first. Blended or mixed textiles pose challenges for mechanical recycling which cannot separate fibers from the blend. However, the separation of fiber blends can be achieved by molecular recycling, i.e., selectively dissolving or depolymerizing specific polymers in the blend. Specifically, the separation of cotton and polyester through dissolution, acidic hydrolysis, acid-catalyzed hydrothermal treatment, and enzymatic hydrolysis is discussed here, followed by the separation of elastane from other fibers by selective degradation or dissolution of elastane. The information synthesized and analyzed in this review can assist stakeholders in the textile and waste management sectors in mapping out strategies for achieving sustainable practices and promoting the shift towards a circular economy. [ABSTRACT FROM AUTHOR]

Plastic mulches have become an essential component of modern agriculture since their introduction in the 1950s. However, disposal of plastic mulches poses serious environmental challenges as plastics that are not considered biodegradable or compostable can take several hundred years to degrade. Each year in the United States, only 9% of overall plastic waste is recycled while 79% is accumulated in landfills or the natural environment. Recycling of plastic mulch is especially constrained due to the contamination that results from their use in farming. Currently, recovered mulches are reported to have 30%–80% surface contamination, primarily from soil and plant debris. Plastic mulch waste is concentrated in areas where they are used and can provide logistical opportunities to the plastic recycling industries. Plastic recycling includes mechanical, advanced (chemical and thermal), and biological methods, that may all be used for polyethylene (PE). Most plastic is recycled using the mechanical method, while advanced and biological methods are promising but face significant financial and technical challenges. For all recycling methods, strategies are needed for managing surface contamination to realize the recycling potential of plastic mulch.

Chemical recycling offers the opportunity to foster the transition towards a circular economy for plastics as a complementary strategy for mechanical recycling. For the implementation of chemical recycling technologies, there are still significant challenges ahead that – besides the definition of binding legal frameworks – need for intensified research: knowledge‐based methods for both the identification of suitable process technologies considering decentralized waste conditions and the design of conversion steps and downstream processing are strongly needed for process development and process evaluation. [ABSTRACT FROM AUTHOR]

Multilayer plastic film use increased in multiple packaging applications due to its versatility and overall increased performance over monolayer structures. However, the performance gains from multiple layers also make recycling difficult because they contain multiple polymers that can be immiscible and burdensome to traditional mechanical recycling operations. A possible solution is the solvent‐targeted recovery and precipitation (STRAP) process, but the effect on the retrieved polymer is still unknown. The STRAP process is applied to two different multilayer films and samples of recovered polymers are evaluated for physical, molecular, and thermal properties. Changes in the molecular weight are not significant, but differences in thermal properties are reported along with the coprecipitation of different polymers. Solvent retention in the polymer matrix from STRAP reduced the glass transition temperature of samples, but enhanced drying recovered it. Heavy metals, such as Cd, Cr, and Pb are not detected, indicating regulatory compliance for different applications. [ABSTRACT FROM AUTHOR]

The plastic pollution to the environment, especially to the ocean, has been draw a lot of attention from the public which results some negative impact to the entire value chain of plastic industry. Circularity and low carbon have been perceived as the solution to tackle these challenges. Efforts required from the feedstock, polymerization, product design and recycling, are all need to be considered. Shifting to the low carbon feedstock is key to reduce the total emission of plastics, while make it recyclable is crucial to achieve low carbon emission for the entire life cycle of plastics. Mechanical recycling aims to make more post-consumer recycles (PCR) being used to some high-end applications to incentivize more plastics being collected and regenerated. The advanced recycling is the last stop for those unrecyclable, avoiding them to the undesired incineration or landfill, and generate value through the pyrolysis or gasification process. The scale is key to make it profitable and sustainable.

Disposal of plastic waste has become a widely discussed issue, due to the potential environmental impact of improper waste disposal. Polyethylene terephthalate (PET) packaging accounted for 44.7% of single-serve beverage packaging in the US in 2021, and 12% of global solid waste. A strategic solution is needed to manage plastic packaging solid waste. Major beverage manufacturers have pledged to reduce their environmental footprint by taking steps towards a sustainable future. The PET bottle has several properties that make it an environmentally friendly choice. The PET bottle has good barrier properties as its single-layer, mono-material composition allows it to be more easily recycled. Compared to glass, the PET bottle is lightweight and has a lower carbon footprint in production and transportation. With modern advancements to decontamination processes in the recycling of post-consumer recycled PET (rPET or PCR), it has become a safe material for reuse as beverage packaging. It has been 30 years since the FDA first began certifying PCR PET production processes as compliant for production of food contact PCR PET, for application within the United States. This article provides an overview of PET bottle-to-bottle recycling and guidance for beverage manufacturers looking to advance goals for sustainability. [ABSTRACT FROM AUTHOR]

Waste generation has been increasing drastically based on the world's population and economic growth. This has significantly affected human health, natural life, and ecology. The utilization of limited natural resources, and the harming of the earth in the process of mineral extraction, and waste management have far exceeded limits. The recycling rate are continuously increasing; however, assessments show that humans will be creating more waste than ever before. Some difficulties during recycling include the significant expense involved during the separation of recyclable waste from non-disposable waste. Machine learning is the utilization of artificial intelligence (AI) that provides a framework to take as a structural improvement of the fact without being programmed. Machine learning concentrates on the advancement of programs that can obtain the information and use it to learn to make future decisions. The classification and separation of materials in a mixed recycling application in machine learning is a division of AI that is playing an important role for better separation of complex waste. The primary purpose of this study is to analyze AI by focusing on machine learning algorithms used in recycling systems. This study is a compilation of the most recent developments in machine learning used in recycling industries. [ABSTRACT FROM AUTHOR]

Advanced plastic waste recycling via pyrolysis and subsequent steam cracking of pyrolysis oils has the potential to partly close the cycle between the petrochemical production of plastics and current end-of-life waste management (i.e., downcycling, incineration, landfilling). However, the greatest obstacle is the complex composition of real plastic waste and their contamination with numerous additives and residues. Consequently, the lower quality of pyrolysis products compared to fossil feedstocks needs to be drastically improved by universally applicable upgrading and decontamination techniques. Techniques range from waste pre-treatment to reduce the halogen and additive contents, via in-situ techniques applied during pyrolysis to post-treatment techniques to purify the obtained pyrolysis oils using hydrotreatment, filtration or adsorption. Incorporated into a petrochemical cluster, high-quality petrochemical feedstocks can be produced from plastic waste, which, combined with electrification, could lead to a CO 2 emission reduction of >90% compared to incineration as the current mostly used disposal method. [Display omitted] • High contamination of plastic waste is the main bottleneck for chemical recycling. • Decontamination techniques are inevitable before, during and/or after pyrolysis. • Dehalogenation is the most effective waste pre-treatment. • Today the most efficient post-treatment is hydrotreatment and adsorption. • Smart combinations of different treatment steps have the highest economic potential. [ABSTRACT FROM AUTHOR]