Carbon nanotubes production from real-world waste plastics and the pyrolysis behaviour

The investigation of the pyrolysis behaviour of real-world waste plastics (RWWP) and using them as the feed-stock to produce carbon nanotubes (CNTs) could serve as an effective solution to address the global waste plastics catastrophe. This research aimed to characterize the pyrolysis behaviour of RWWP via thermogravimetric analysis (TG) and fast pyrolysis-TG/mass spectrometry (Py-TG/MS) analyses. Activation energies (131.04 kJ mol-1 -171.04 kJ mol-1) for RWWP pyrolysis were calculated by three methods: Flynn-Wall-Ozawa (FWO) method, Kissinger-Akahira-Sunose (KAS) method, and Starink method. Py-TG/MS results indicated that the RWWP could be identified as polystyrene (RWWP-1), polyethylene (RWWP-2), polyethylene terephthalate (RWWP-3, 4), and polypropylene (RWWP-5, 6). In addition, RWWP-1, 2, 5, 6 outperform RWWP-3 and 4 as sources of carbon for producing CNTs. The results showed a high carbon yield of 32.21 wt% and a high degree of CNT purity at 93.04%.

Automated summary

Investigating the pyrolysis behavior of real-world waste plastics (RWWP) and using them to produce carbon nanotubes (CNTs) could be an effective solution to the global waste plastics crisis. Thermogravimetric analysis (TG) and fast pyrolysis-TG/mass spectrometry (Py-TG/MS) were used to characterize the pyrolysis behavior of RWWP. The activation energies for RWWP pyrolysis were calculated using three methods, and the results showed that polystyrene, polyethylene, polyethylene terephthalate, and polypropylene were present in RWWP. Among them, polystyrene, polyethylene, and polypropylene were found to be better carbon sources for producing CNTs. The research also demonstrated a high carbon yield of 32.21 wt% and a high degree of CNT purity at 93.04%.