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The ever-growing plastic production and the caused concerns of plastic waste accumulation have stimulated the need for waste plastic chemical recycling/valorization. Current methods suffer from harsh reaction conditions and long reaction time. Herein we demonstrate a non-thermal plasma-assisted method for rapid hydrogenolysis of polystyrene (PS) at ambient temperature and atmospheric pressure, generating high yield (>40 wt%) of C1–C3 hydrocarbons and ethylene being the dominant gas product (Selectivity of ethylene, SC2H4 > 70%) within ~10 min. The fast reaction kinetics is attributed to highly active hydrogen plasma, which can effectively break bonds in polymer and initiate hydrogenolysis under mild condition. Efficient hydrogenolysis of post-consumer PS materials using this method is also demonstrated, suggesting a promising approach for fast retrieval of small molecular hydrocarbon modules from plastic materials as well as a good capability to process waste plastics in complicated conditions.
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Quantifying the Chemical Composition and Real-Time Mass Loading of Nanoplastic Particles in the Atmosphere Using Aerosol Mass Spectrometry
Plastic debris, including nano-plastic particles (NPPs), has emerged as an important global environmental issue due to its detrimental effects on human health, ecosystems, and climate. Atmospheric processes play an important role in the transportation and fate of plastic particles in the environment. In this study, a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was employed to establish the first online approach for identification and quantification of airborne submicron polystyrene (PS) NPPs from both laboratory-generated and ambient aerosols. The fragmentation ion C8H8+ is identified as the major tracer ion for PS nanoplastic particles, achieving a one-hour detection limit being 4.96 ng/m3. Ambient PS NPPs measured at an urban location in Texas are quantified to be 30 ± 20 ng/m3 by applying the AMS data with a constrained positive matrix factorization (PMF) method using the multilinear engine (ME-2). Careful analysis of ambient data reveals that atmospheric PS NPPs were enhanced as air masses passed through a waste incinerator plant, suggesting incineration of waste may serve as a source of ambient NPPs. The online quantification of NPPs achieved through this study can significantly improves understandings of the source, transport, fate, and climate effects of atmospheric NPPs to mitigate this emerging global environmental issue.
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- Award ID(s):
- 2131369
- PAR ID:
- 10545698
- Editor(s):
- Hornbuckle, Keri C
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Environmental Science & Technology
- Edition / Version:
- 1
- Volume:
- 58
- Issue:
- 7
- ISSN:
- 0013-936X
- Page Range / eLocation ID:
- 3363-3374
- Subject(s) / Keyword(s):
- Nanoplastic Particles (NPPs), Aerosol Mass Spectrometer, Polystyrene, Positive Matrix Factorization (PMF), Multilinear Engine (ME-2), Real-time Measurement
- Format(s):
- Medium: X Size: 3.2MB Other: pdf
- Size(s):
- 3.2MB
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1021/acs.est.3c10286
