Catalytic oxidation of polystyrene to aromatic oxygenates over a graphitic carbon nitride catalyst

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Авг. 16, 2022

The continuous increase in manufacturing coupled with the difficulty of recycling plastic products has generated huge amounts waste plastics. Most existing chemical and upcycling methods suffer from harsh conditions poor product selectivity. Here we demonstrate a photocatalytic method to oxidize polystyrene aromatic oxygenates under visible light irradiation using heterogeneous graphitic carbon nitride catalysts. Benzoic acid, acetophenone, benzaldehyde are dominant liquid phase when conversion reaches >90% at 150 °C. For transformation 0.5 g waste, 0.36 is obtained. reaction mechanism also investigated various characterization procedes via activation form hydroxyl carbonyl groups over its backbone C-H bond oxidation which followed by oxidative breakage C-C further processes oxygenates.

Язык: Английский

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Biological Degradation of Plastics and Microplastics: A Recent Perspective on Associated Mechanisms and Influencing Factors

Microorganisms, Год журнала: 2023, Номер 11(7), С. 1661 - 1661

Опубликована: Июнь 26, 2023

Plastic and microplastic pollution has caused a great deal of ecological problems because its persistence potential adverse effects on human health. The degradation plastics through biological processes is significance for health, therefore, the feasibility plastic by microorganisms attracted lot attention. This study comprises preliminary discussion biodegradation mechanism advantages roles different bacterial enzymes, such as PET hydrolase PCL-cutinase, in polymers, PCL, respectively. With particular focus their modes action enzymatic mechanisms, this review sums up studies microplastics related to mechanisms influencing factors, along with enzymes enhancing synthetic process. In addition, also affected additives plasticizers. Plasticizers composition can cause harmful impacts. To further improve efficiency various pretreatments biodegradation, which significant reduction toxic pollution, were preliminarily discussed here. existing research data show large number involved though specific have not been thoroughly explored yet. Therefore, there employing strains efficient health safety.

Язык: Английский

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Chemical upcycling of polyethylene, polypropylene, and mixtures to high-value surfactants

Science, Год журнала: 2023, Номер 381(6658), С. 666 - 671

Опубликована: Авг. 10, 2023

Conversion of plastic wastes to fatty acids is an attractive means supplement the sourcing these high-value, high-volume chemicals. We report a method for transforming polyethylene (PE) and polypropylene (PP) at ~80% conversion with number-average molar masses up ~700 670 daltons, respectively. The process applicable municipal PE PP their mixtures. Temperature-gradient thermolysis key controllably degrading into waxes inhibiting production small molecules. are upcycled by oxidation over manganese stearate subsequent processing. ꞵ-scission produces more olefin wax yields higher acid-number than does ꞵ-scission. further convert large-market-volume surfactants. Industrial-scale technoeconomic analysis suggests economic viability without need subsidies.

Язык: Английский

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Catalytic strategies for upvaluing plastic wastes

Chem, Год журнала: 2022, Номер 8(11), С. 2912 - 2923

Опубликована: Сен. 7, 2022

Язык: Английский

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Microplastic materials in the environment: Problem and strategical solutions

Progress in Materials Science, Год журнала: 2022, Номер 132, С. 101035 - 101035

Опубликована: Окт. 19, 2022

Язык: Английский

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Bridging Plastic Recycling and Organic Catalysis: Photocatalytic Deconstruction of Polystyrene via a C–H Oxidation Pathway

ACS Catalysis, Год журнала: 2022, Номер 12(14), С. 8155 - 8163

Опубликована: Июнь 23, 2022

Chemical recycling of synthetic polymers represents a promising strategy to deconstruct plastic waste and make valuable products. Inspired by small-molecule C-H bond activation, visible-light-driven reaction is developed polystyrene (PS) into ∼40% benzoic acid as well ∼20% other monomeric aromatic products at 50 °C ambient pressure. The practicality this demonstrated deconstruction real-world PS foam on gram scale. proposed proceed via oxidation pathway, which supported theoretical calculations experimental results. Fluorescence quenching experiments also support efficient electron transfer between the photocatalyst polymer substrate, providing further evidence for mechanism. This study introduces concepts from catalysis provides method tackle global crisis pollution.

Язык: Английский

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Plastic Waste Valorization by Leveraging Multidisciplinary Catalytic Technologies

ACS Catalysis, Год журнала: 2022, Номер 12(15), С. 9307 - 9324

Опубликована: Июль 18, 2022

Plastic waste triggers a series of concerns because its disruptive impact on the environment and ecosystem. From point view catalysis, however, end-of-life plastics can be seen as an untapped feedstock for preparation value-added products. Thus, development diversified catalytic approaches valorization is urgent. Previous reviews this field have systematically summarized progress made plastic reclamation. In review, we emphasize design processes by leveraging state-of-the-art technologies from other developed fields to derive valuable polymers, functional materials, chemicals plastics. The principles, mechanisms, opportunities chemical (thermo-, electro-, photocatalytic) well biocatalytic ones are discussed, which may provide more insights future processes. Finally, outlooks perspectives accelerate toward feasible economy discussed.

Язык: Английский

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Photoredox-Catalyzed Plastic Waste Conversion: Nonselective Degradation versus Selective Synthesis

ACS Catalysis, Год журнала: 2023, Номер 13(6), С. 3575 - 3590

Опубликована: Фев. 27, 2023

Plastic waste pollution is becoming one of the most pressing environmental crises due to large-scale production without satisfactory recycling schemes, especially with outbreak COVID-19 pandemic in recent years. Upcycling plastic into valuable chemicals powered by solar energy presents a substantially untapped opportunity turn treasure. In this review, fundamental principles from nonselective degradation selective synthesis are first clarified. Then, we aim outline representative advances photoredox-based catalytic conversion. Particular emphasis placed on valorization regarding versus synthesis. Finally, present challenges and individual insights for further exploration conversion domain. It anticipated that timely critical review would provide an instructive direction foresight plastics value-added chemical feedstocks, thus stimulating development circular sustainable economy coming decades.

Язык: Английский

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Integrated strategy for the synthesis of aromatic building blocks via upcycling of real-life plastic wastes

Chem, Год журнала: 2022, Номер 8(9), С. 2472 - 2484

Опубликована: Июнь 21, 2022

Язык: Английский

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Mixed Plastics Wastes Upcycling with High-Stability Single-Atom Ru Catalyst

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(41), С. 22836 - 22844

Опубликована: Окт. 5, 2023

Mixed plastic waste treatment has long been a significant challenge due to complex composition and sorting costs. In this study, we have achieved breakthrough in converting mixed wastes into single chemical product using our innovative single-atom catalysts for the first time. The Ru catalyst can convert ∼90% of real methane products (selectivity >99%). unique electronic structure sites regulates adsorption energy intermediates, leading rapid decomposition plastics superior cycle stability compared traditional nanocatalysts. global warming potential entire process was evaluated. Our proposed carbon-reducing utilizing launches new era valorization.

Язык: Английский

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