Catalytic pyrolysis of waste polyethylene terephthalate granules using a Lewis-Bronsted acid sites catalyst

Among municipal polymer wastes, polyethylene terephthalate (PET) is unique due to its widespread use in the plastics industry. The wide range of gaseous products produced during the catalytic cracking of PET makes it one of the most difficult polymer products to recycle. The aim of this study is to achieve more liquid products in pyrolysis of PET by introducing a Lewis-Bronsted acid sites catalyst. The pyrolysis of polyethylene terephthalate (PET) was studied in a semi-batch reactor using the Lewis-Bronsted acid sites catalyst. The experiments were carried out under isothermal condition to determine the kinetic parameters, product distribution, catalyst/PET mass ratio, and the effect of temperature on the conversion rate. The reaction products consisted of a gas, solid and liquid phase with a maximum liquid product of 6% at 350 degrees C. The optimum catalyst/PET mass ratio and temperature were also determined. In addition, the reaction order and activation energy for the reaction were determined. Since few detailed studies on the kinetics of PET pyrolysis by thermogravimetric analysis have been reported in the literature, this work presents the results of this investigation using the kinetic model.

Automated summary

This study aims to achieve more liquid products in the pyrolysis of PET by introducing a Lewis-Bronsted acid sites catalyst. The experimental results show that the maximum liquid product is 6% under certain conditions, and the optimum catalyst/PET mass ratio and temperature have been determined.