Remediating plastic waste into carbon nanotubes.
Polyethylene-based used plastics needs hundreds of years to degrade in atmospheric conditions. Thus, in addition to conventional recycling facilities for polymer waste (PW), innovative solutions are required. This paper describes a solvent-free process that converts PW such as low-density (LD) and high-density polyethylene (HDPE) into multi-walled carbon nanotubes (MWCNTs) via thermal dissociation in the presence of chemical catalysts in a closed system under autogenic pressure. Specifically, the optimization of process parameters, e.g. selection and amounts of catalysts, density effects of PE, autogenic pressure measurements, and a reaction mechanism for the growth of MWCNTs is explained. The composition, morphology, and atomic structure of the as-obtained MWCNTs are characterized employing advanced structural, spectroscopic, and imaging techniques. We have measured the unique magnetic and electrical conductivity behaviours of as-prepared MWCNTs to assess their potential applications as advanced materials. This reproducible process presents an opportunity to use PW as a feedstock for the production of MWCNTs, industrially significant value-added products. Among the known methods for the fabrication of MWCNTs, the present controlled dissociation of PW is one of the inexpensive and straightforward methods.
Intense Pulse Neutron Source, Argonne National Laboratory, Argonne, IL 60439, USA. pol@anl.gov
Vilas Ganpat
VG
Pol
Pappanan
P
Thiyagarajan
D003247:Conservation of Natural Resources / Q000379:methods*; D004578:Electron Spin Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D010969:Plastics / Q000737:chemistry*; D011095:Polyethylenes / Q000737:chemistry*; D014961:X-Ray Diffraction
D037742:Nanotubes, Carbon; D010969:Plastics; D011095:Polyethylenes