Recent Progress in Polyolefin Plastic: Polyethylene and Polypropylene Transformation and Depolymerization Techniques

Molecules, Journal Year: 2024, Volume and Issue: 30(1), P. 87 - 87

Published: Dec. 29, 2024

This paper highlights the complexity and urgency of addressing plastic pollution, drawing attention to environmental challenges posed by improperly discarded plastics. Petroleum-based polymers, with their remarkable range physical properties, have revolutionized industries worldwide. Their versatility—from flexible rigid hydrophilic hydrophobic—has fueled an ever-growing demand. However, versatility has also contributed a massive global waste problem as plastics pervade virtually every ecosystem, from depths oceans most remote terrestrial landscapes. Plastic pollution manifests not just visible waste—such fishing nets, bottles, garbage bags—but microplastics, infiltrating food chains freshwater sources. crisis is exacerbated unsustainable linear model production consumption, which prioritizes convenience over long-term health. The mismanagement only pollutes ecosystems but releases greenhouse gases like carbon dioxide during degradation incineration, thereby complicating efforts achieve climate sustainability goals. Given that mechanical recycling addresses fraction macroplastics, innovative approaches are needed improve this process. Methods pyrolysis hydrogenolysis offer promising solutions enabling chemical transformation depolymerization into reusable materials or valuable feedstocks. These advanced methods can support circular economy reducing creating high-value products. In article, focus on underscores need move beyond traditional recycling. exemplify potential for science technology mitigate while aligning objectives. Recent advances in polyolefins recycling, breaking down at molecular level create feedstocks new products fuels. Pyrolysis produces oil syngas, applications renewable energy chemicals. some process include scalability, feedstock variety, standardization, well concerns about emissions. Companies Shell ExxonMobil investing heavily overcome these barriers efficiencies. By leveraging transformative strategies, we reimagine lifecycle address one pressing our time. review updates knowledge fields derived based recent works available literature, highlighting techniques used, types obtained, highest yields.

Language: Английский

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Efficient Hydrogenolysis of Consumer-Grade High-Density Polyethylene Wastes over MgAl-Layered Double Oxide-Supported Ru Catalysts

ACS Sustainable Chemistry & Engineering, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 20, 2024

Hydrogenolysis of consumer-grade high-density polyethylene (HDPE) is a pivotal strategy for upcycling plastic waste into value-added fuels. Though Ru catalysts demonstrated activity in the hydrogenolysis inert C–C bonds HDPE, precise design nanoparticles still represents critical challenge to boost performance. Here, ultrafine (∼1 nm) supported on MgAl-layered double oxides (MgAl-LDO) exhibited selectivity over 90% liquid fuels, lubricants, and waxes HDPE. By tuning thermal treatments Mg/Al ratios, Ruδ+/Ru0 ratio acidity/basicity MgAl-LDO were determined as performance descriptors. Notably, confining effects layered structure can be optimized facilitate effective dispersion nanoparticles, even at elevated loadings up 9%. Moreover, Ru/Mg1Al-LDO catalyst good applicability various HDPE substrates excellent stability, maintaining five recycling runs.

Language: Английский

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The role of size and structure of catalytic active sites in polyolefin hydrogenolysis

Chem Catalysis, Journal Year: 2024, Volume and Issue: 4(9), P. 101076 - 101076

Published: Aug. 20, 2024

Language: Английский

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Production of Branched Alkanes by Upcycling of Waste Polyethylene over Controlled Acid Sites of SO4/ZrO2‐Al2O3 Catalyst

Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 14, 2024

Abstract Branched alkanes, which enhance the octane number of gasoline, can be produced from waste polyethylene. However, achieving highly selective production branched alkanes presents a significant challenge in upcycling Here, we report one‐pot process to convert polyethylene into gasoline‐range hydrocarbons (C 4 –C 13 ) with yield 73.3 % over SO /ZrO 2 ‐Al O 3 catalyst at 280 °C. The proportion reaches 90.1 within C fraction. Incorporation sulfate group endows strong Lewis acid sites and weak moderate Brønsted sites. In situ X‐ray absorption, infrared spectroscopy, small angle neutron scattering, DFT calculations reveal that activation occurs through synergy between groups (Zr sites). preferentially catalyze isomerization type A β‐scission processes, favors formation while suppressing competing reactions produce straight‐chain alkanes.

Language: Английский

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Two-step conversion of waste plastic into light olefins and aromatics on metal-free carbon felt catalyst under radiofrequency heating

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 158158 - 158158

Published: Nov. 1, 2024

Language: Английский

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