Plastic upcycling into multi-walled carbon nanotubes via tandem zeolites and Fe/SiO2-based catalysts
Journal
Journal of the Taiwan Institute of Chemical Engineers
Journal Volume
185
Start Page
106674
ISSN
18761070
Date Issued
2026-08
Author(s)
Matsagar, Babasaheb M.
Liao, Weisheng
Chang, Yu-Chia
Raju, Abhay
Hsieh, Cheng-Kuan
Wu, Kevin C.-W.
Abstract
Background Plastic waste has recently been recognized as a promising carbon-rich feedstock for producing high-value carbon materials. Among these, multi-walled carbon nanotubes (MWCNTs) are particularly attractive due to their superior economic and functional value. However, direct conversion of plastics into CNTs remains under-explored, primarily because the broad hydrocarbon distribution generated during pyrolysis hinders selective nanotube growth. Methods To overcome this challenge, zeolites with varying acidities were introduced in the pyrolysis step to tune the composition of pyrolysis vapors. A finely dispersed Fe/SiO₂ catalyst (20–30 nm Fe nanoparticles) was employed in a two-stage pyrolysis-catalysis process. This strategy enabled selective carbon nanotube growth from plastic-derived gases. Significant Findings Using ultra-stable zeolite Y (USY) and Fe/SiO₂ catalyst under optimized conditions, a high MWCNT yield of 15% was achieved. The process was further evaluated with various post-consumer plastics, including low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polyethylene terephthalate (PET), and polystyrene (PS), confirming the feasibility and versatility of this plastic upcycling strategy and revealing the influence of plastic type on the formation of value-added carbon nanomaterials.
Subjects
Carbon nanomaterials
Metal nanoparticles
Multi-walled carbon nanotubes
Plastic upcycling
Zeolites
Publisher
Taiwan Institute of Chemical Engineers
Type
journal article