Catalytic conversion of hard plastics to valuable carbon nanotubes

The management of waste hard plastics is a big challenge in the world. Conventional pyrolysis and gasification of hard plastics have been extensively reported. However, producing high values carbon nanotubes as the main product or byproduct from hard plastics has been rarely reported. In this work, we studied and reported this work by using pyrolysis of phenolic formaldehyde resin producing high value carbon nanotubes to promote the economic competitiveness of the technology. The produced carbon nanotubes were characterized by scanning electronic microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy and temperature programme oxidation. The yield of CNTs using the Ni catalysts is about 24.07 % and its purity is 93.13 %. Compared with the Ni catalysts, the Fe catalysts have higher yield and purity of CNTs, reaching 34.39 % and 97.45 %, respectively. Through transmission electron microscopy and Raman characterization, it is found that the graphitization quality of CNTs produced from Fe catalysts is higher than that of the CNTs produced from Ni catalysts.