Kinetic Study of Catalytic Cracking of Mixed Polymers (HDPE, LDPE, PP, PS, PVC, PET) into Middle Distillate Product  


Waste polymer recycling has received a great attention due to increasing amounts of waste polymers generate enormous environmental problems. This study investigates catalytic cracking of mixture of polymers (HDPE, LDPE, 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 AIT100 that is a novel catalyst made in research center of Abadan institute of technology. The catalyst made is in acidic catalyst group that is suitable for cracking of heavy hydrocarbons. Kinetic analysis is based on Arrhenius equation. The results indicates that increasing of the catalyst leads to increasing of the reaction constant and also decrease on activation energy required to cracking of the polymers mixed. All the 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. The experiments show that increasing of the catalyst leads to converting more polymers to middle distillate products.

Key words: Environment, cracking, kinetic analysis, fuel, mixed plastics, catalyst.

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