Upcycling Waste Plastics into Multi-Walled Carbon Nanotube Composites via NiCo2O4 Catalytic Pyrolysis

In this work, multi-walled carbon nanotube composites (MWCNCs) were produced by catalytic pyrolysis of post-consumer plastics with aluminium oxide-supported nickel, cobalt, and their bimetallic (Ni/alpha-Al2O3, Co/alpha-Al2O3, and NiCo/alpha-Al2O3) oxide-based catalysts. The influence of catalyst composition and catalytic reaction temperature on the carbon yield and structure of CNCs were investigated. Different temperatures (800, 900, 950, and 1000 & DEG;C) and catalyst compositions (Ni, Co, and Ni/Co) were explored to maximize the yield of carbon deposited on the catalyst. The obtained results showed that at the same catalytic temperature (900 & DEG;C), a Ni/Co bimetallic catalyst exhibited higher carbon yield than the individual monometallic catalysts due to a better cracking capability on carbon-hydrogen bonds. With the increase of temperature, the carbon yield of the Ni/Co bimetallic catalyst increased first and then decreased. At a temperature of 950 & DEG;C, the Ni/Co bimetallic catalyst achieved its largest carbon yield, which can reach 255 mg g(plastic)(-1). The growth of CNCs followed a particle-wire-tube mechanism for all studied catalysts. This work finds the potential application of complex oxide composite material catalysts for the generation of CNCs in catalytic pyrolysis of wasted plastic.

Automated summary

In this study, multi-walled carbon nanotubes composites (MWCNCs) were produced by catalytic pyrolysis of post-consumer plastics using complex oxide composite material catalysts. The Ni/Co bimetallic catalyst exhibited higher carbon yield at 900°C compared to monometallic catalysts. This research highlights the potential application of complex oxide composite material catalysts in producing CNCs from waste plastics through catalytic pyrolysis.