33Kinetic Study of Catalytic Degradation of Mixed Waste Plastics into Gasoline and Diesel Product


Waste polymer recycling has received a great attention due to increasing amounts of these materials which generate enormous environmental problems. This study investigates catalytic cracking of composite polymers (PE, PP, PS, PVC and PET) as an effective method to recycle these polymers and focuses on kinetic parameters of the reaction. The catalyst chosen is a novel catalyst made in research center of faculty. Kinetic analysis is based on Arrhenius equation. The results indicate that increasing of the catalyst leads more reaction constant and less activation energy required to cracking of the composite polymers. All experiments have been carried out at temperature of 380-450 ºC, using 10-50% catalyst/polymer ratio. Finally, the maximum yield of the reaction obtained in high temperature 450° C and catalyst ratio of 50% that include 84% liquid hydrocarbon (C5-C10) and 13% gas (C1- C4) with less percent of residue.

Keywords: Environment, cracking, kinetic analysis, fuel, mixed plastics, catalyst.


  • Q. Zhou, L. Zheng, Y.Z. Wang, GM. Zhao and B. Wang, Catalytic degradation of low-density polyethylene and polypropylene using modified ZSM-5 zeolites, Polymer Degradation and Stability., 84, 493 (2004).
  • J. Scheirs, “Polymer Recycling”, J. Wiley & Sons., (1998).
  • G. P. Karayannidis and D. S. Achilias, The chemical recycling of PET in the framework of sustainable development, Water, Air & Soil Pollution: Focus., 4, 385 (2004).
  • T. Paul, Williams and Ranbir. Bagri, Hydrocarbon gases and oils from the recycling of polystyrene waste by catalytic pyrolysis, international journal of energy research., 28, 31 (2004).
  • T. Maharana, Y. S. Negi and B. Mohanty, Review article: Recycling of polystyrene, Polymer-Plastics Technology and Engineering., 46, 729 (2007).
  • W.Zhao, S. Hasegawa, J. Fugito, F. Yoshii, T. Sasaki, K. Makuuchi, J. Sun and S. Nishimoto, Effects of zeolites on the pyrolysis of polypropylene, Polymer Degradation and Stability., 53, 129 (1996).
  •  W.C. McCaffrey, M.R. Kamal and D.G. Cooper, Thermolysis of polyethylene, Polymer Degradation and Stability., 47, 133 (1995).
  •  S.Y. Lee, J.H. Yoon, J.R. Kim and D.W. Park, Degradation of polystyrene using clinoptilolite catalysts, Analytical and Applied Pyrolysis., 64, 71 (2002).
  • D.S. Achilias, I. Kanellopoulou, P. Megalokonomos, E. Antonakou and A. Lappas, Chemical Recycling of Polystyrene by Pyrolysis: Potential Use ofthe Liquid Product for the Reproduction of Polymer, Macromolecular, 292, 923 (2007).
  • S.M. Al-Salem, P. Lettieri and J. Baeyens, Recycling and recovery routes of plastic solid waste (PSW): A review, Waste Management., 29, 2625 (2009).
  • G.P. Karayannidis and S. Dimitris, Chemical Recycling of Poly(ethylene terephthalate), Macromolecular Materials and Engineering., 292, 128 (2007).
  •  G. Audisio and A. Silvani, Catalytic thermal degradation of polymers: Degradation ofpolypropylene, Analytical and Applied Pyrolysis., 7, 83 (1984).
  • G. Manos, A. Garforth and J. Dwyer, Catalytic degradation of high-density polyethylene over different zeolitic structures, Industrials & Engineering Chemistry Research., 39, 1198 (2000).
  • H. Ukei, T. Hirose, S. Horikawa, Y. Takai, M. Taka, N. Azuma and A. Ueno, Catalytic degradation of polystyrene into styrene and a design of recyclable polystyrene with dispersed catalysts, Catalysis Today., 62, 67 (2000).
  • J. Aguado, J. L. Sotelo, D. P. Serrano, J. A. Calles, and J. M. Escola, Catalytic conversion of polyolefins into liquid fuels over MCM-41: Comparison with ZSM-5 and amorphous SiO2-Al2O3, Energy & Fuels., 11, 1225 (1997).
  • A. Lopez, I. De Marco, B.M. Caballero, M.F. Laresgoiti, A. Adrados and A. Aranzabal, Catalytic pyrolysis of plastic wastes with two different types of catalysts: ZSM-5 zeolite and red mud, Applied Catalysis B: Environmental., 104, 211 (2011).
  • J. Shah, J.M. Rasul, F. Mabood and F. Jabeen, Catalytic pyrolysis of LDPE leads to valuable resource recovery and reduction ofwaste problems, Energy Convers Manage., 51, 2791 (2010).
  • J.M. Encinar and J.F. Gonza’lez, Pyrolysis of synthetic polymers and plastic wastes. Kinetic study, Fuel Process Technol., 89, 678 (2008).
  • G.D.L. Puente, C. Klocker and U .Sedran, Conversion of waste plastics into fuels recycling polyethylene in FCC, Applied Catalysis B: Environmental., 36, 279 (2002).
  • S.M. Salem and P. Lettieri, Kinetic study of high density polyethylene (HDPE) pyrolysis, Chemical Engineering Research and Design., 88, 1599 (2010).
  • F. Tiziano, B. Giulia, C. Mauro, R. Eliseo and D. Mario, Kinetic modeling of the thermal degradation of polyethylene and polystyrene mixtures, Analytical Applied Pyrolysis., 70, 761 (2003).
  • D. Hooshmand, B. Roozbehani and A. Badakhshan, Thermal and Catalytic Degradation of Polystyrene with a Novel Catalyst, International Journal of Science & Emerging Technologies., 5, 234 (2013).
  • S. A. Sakaki, B. Roozbehani, M. Shishesaz and N. Abdollahkhani, Catalytic degradation of the mixed polyethylene and polypropylene into middle distillate products, Clean Technologies and Environmental Policy., 16, 901 (2013).
  • M.A. Jaskiewicz, Production of Liquid Fuels from Recycled Plastics using Acidic HNaY Catalysts., (2011).
  • T.T. Weia, K.J. Wua, S.L. Leeb and Y.H. Lin, Chemical recycling of post-consumer polymer waste over fluidizing cracking catalysts for producing chemicals and hydrocarbon fuels., Resources, Conservation and Recycling., 54, 952 (2010).
  • K.H. Lee and D.H. Shin, Catalytic degradation of waste polyolefinic polymers using spent FCC catalyst with various experimental variables, Korean Journal of Chemical Engineering, 20, 89 (2003).
  • N.S. Akpanudoh, K. Gobin and G. Manos, Catalytic degradation of plastic waste to liquid fuel over commercial cracking catalysts Effect of polymer to catalyst ratio/acidity content, Journal of Molecular Catalysis A: Chemical., 235, 67 (2005).
  • J.M. Encinar and J.F. Gonzalez, Pyrolysis of synthetic polymers and plastic wastes: Kinetic study, Fuel Processing Technology., 89, 678 (2008).
  • S. Sarathy, M.D. Wallis and S. Bhatia, Effect of Catalyst Loading on Kinetics of Catalytic Degradation of High Density Polyethylene: Experiment and Modelling, Chemical Engineering Science., 65, 796 (2010).
  • N. Miskolczi, L. Bartha, Gy. Dea’ K, B. Jo’ Ver and D. Kallo’, Kinetic Model of The Chemical Recycling of Waste Polyethylene Into Fuels, Process Safety and Environmental Protection., 82, 223 (2004).
  • J.M. Encinar and J.F. Gonzalez, Pyrolysis of Synthetic Polymers and Plastic Wastes. Kinetic Study, Fuel Processing Technology., 89, 678 (2008).
  • Y.H. Lin A, W.H. Hwu, M.D. Ger, T.F. Yeh and J. Dwyer, A Combined Kinetic and Mechanistic Modeling of The Catalytic Degradation of Polymers, Journal of Molecular Catalysis A: Chemical., 171, 143 (2001).
  •  Roozbehani, B., Motevassel, M., Mirdrikvand, M., Moqadam, S. I., & Kharaghani, A. Gasoline production from a polymeric urban disposal mixture using silica–alumina catalyst. Clean Technologies and Environmental Policy, 1-14
  • Roozbehani, B., Dashtbozorg, A. Catalysts and Natural Gas Partial Oxidation. American Journal of Oil and Chemical Technologies: Volume 4.4 (2016)
  • Motevassel, M., Roozbehani, B., and Shahi, A. “Catalytic Degradation of Mixed Polymers into Environmental Friendly and Useful Products.” American Journal of Oil and Chemical Technologies: Volume 2.12 (2014).