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Title: Upcycling : converting waste plastics into paramagnetic, conducting, solid, pure carbon microspheres.

Abstract

The recent tremendous increase in the volume of waste plastics (WP) will have a harmful environmental impact on the health of living beings. Hundreds of years are required to degrade WP in atmospheric conditions. Hence, in coming years, in addition to traditional recycling services, innovative 'upcycling' processes are necessary. This article presents an environmentally benign, solvent-free autogenic process that converts various WP [low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene terephthalate (PET), polystyrene (PS), or their mixtures] into carbon microspheres (CMSs), an industrially significant, value-added product. The thermal dissociation of these individual or mixed WP in a closed reactor under autogenic pressure (1000 psi) produced dry, pure powder of CMSs. In this paper, the optimization of process parameters such as the effect of mixing of WP with other materials, and the role of reaction temperature and time are reported. Employing advanced analytical techniques, the atomic structure, composition, and morphology of as-obtained CMSs were analyzed. The room-temperature paramagnetism in CMSs prepared from waste LDPE, HDPE, and PS was further studied by electron paramagnetic resonance (EPR). The conducting and paramagnetic nature of CMSs holds promise for their potential applications in toners, printers, paints, batteries, lubricants, and tires.

Authors:
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); EE
OSTI Identifier:
982674
Report Number(s):
ANL/CSE/JA-66185
Journal ID: 0013-936X; TRN: US201015%%1281
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Environ. Sci. Technol.; Journal Volume: 44; Journal Issue: 12 ; Jun. 15, 2010
Country of Publication:
United States
Language:
ENGLISH
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 54 ENVIRONMENTAL SCIENCES; CARBON; ELECTRON SPIN RESONANCE; ENVIRONMENTAL IMPACTS; MICROSPHERES; PLASTICS; WASTES

Citation Formats

Pol, V. Upcycling : converting waste plastics into paramagnetic, conducting, solid, pure carbon microspheres.. United States: N. p., 2010. Web. doi:10.1021/es100243u.
Pol, V. Upcycling : converting waste plastics into paramagnetic, conducting, solid, pure carbon microspheres.. United States. doi:10.1021/es100243u.
Pol, V. Tue . "Upcycling : converting waste plastics into paramagnetic, conducting, solid, pure carbon microspheres.". United States. doi:10.1021/es100243u.
@article{osti_982674,
title = {Upcycling : converting waste plastics into paramagnetic, conducting, solid, pure carbon microspheres.},
author = {Pol, V.},
abstractNote = {The recent tremendous increase in the volume of waste plastics (WP) will have a harmful environmental impact on the health of living beings. Hundreds of years are required to degrade WP in atmospheric conditions. Hence, in coming years, in addition to traditional recycling services, innovative 'upcycling' processes are necessary. This article presents an environmentally benign, solvent-free autogenic process that converts various WP [low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene terephthalate (PET), polystyrene (PS), or their mixtures] into carbon microspheres (CMSs), an industrially significant, value-added product. The thermal dissociation of these individual or mixed WP in a closed reactor under autogenic pressure (1000 psi) produced dry, pure powder of CMSs. In this paper, the optimization of process parameters such as the effect of mixing of WP with other materials, and the role of reaction temperature and time are reported. Employing advanced analytical techniques, the atomic structure, composition, and morphology of as-obtained CMSs were analyzed. The room-temperature paramagnetism in CMSs prepared from waste LDPE, HDPE, and PS was further studied by electron paramagnetic resonance (EPR). The conducting and paramagnetic nature of CMSs holds promise for their potential applications in toners, printers, paints, batteries, lubricants, and tires.},
doi = {10.1021/es100243u},
journal = {Environ. Sci. Technol.},
number = 12 ; Jun. 15, 2010,
volume = 44,
place = {United States},
year = {Tue Jun 15 00:00:00 EDT 2010},
month = {Tue Jun 15 00:00:00 EDT 2010}
}
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