Carbon nanotubes formation on clay and fly ash from catalytic thermal decomposition of recycled polypropylene

  • Nur A. Atikah Kamaruddin (Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis) ;
  • Norzilah A. Halif (Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis) ;
  • Siti A. Hussin (Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis) ;
  • Mohd. N. Mazlee (Centre of Excellence for Frontier Materials Research, Universiti Malaysia Perlis)
  • Received : 2023.08.24
  • Accepted : 2024.01.03
  • Published : 2024.06.25


Fly ash, plastic waste, and clay are mineral materials and residues commonly found in Malaysia. In this study, these materials were fully utilized as raw materials for synthesizing carbon nanotubes (CNTs). Recycled polypropylene, previously used as a food container, served as a carbon source. Fly ash and clay were explored as potential substrates for CNTs growth. The recycled polypropylene was thermally decomposed at 900 ℃ in an inert environment for 90 minutes. Carbon atoms released during this process were deposited on fly ash and clay substrates, which had been immersed in a ferrocene solution to provide a metal catalyst for CNTs growth. The deposited products were characterized using a Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). Morphological analysis revealed that both fly ash and clay were coated with fiber-like structures, confirmed to be CNTs based on a diffraction peak around 26° from the XRD pattern. In conclusion, clay and fly ash demonstrate the potential to be utilized as substrates for CNTs formation.



This study was supported by Ministry of Higher Education (MoHE) Malaysia through the Fundamental Research Grant Scheme (FRGS) under a grant number of FRGS/1/2022/TK08/UNIMAP/02/76.


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