Insight the influence of the catalyst basicity on glycolysis behavior of Polyethylene terephthalate (PET)

Although polyethylene terephthalate (PET) is one of the most prevalent plastics, a cumulative disposal of PET waste has caused adverse effects on both economy and environment. Catalytic glycolysis of PET waste has emerged as a prevalent and sustainable pathway to address this problem. Due to the limitations of recovery and recycling, the catalytic development trend for PET glycolysis has recently changed from homogenous to heterogeneous designs. Herein, metal oxides with different basicity, including calcium, cerium, and cobalt, were supported on alumina and first employed in the glycolysis process of waste PET plastic. A plausible mechanism is proposed and reveals the correlation between the basicity of as-prepared catalyst and glycolysis performances. Among these catalysts, 10%Ce/Al2O3 exhibited a complete conversion of waste PET with the highest selectivity to the main product BHET. There is no significant drop in catalytic activity after five consecutive runs. Furthermore, the excellent quality of the monomer product BHET was confirmed via different analysis techniques. This work has contributed to a promising notion for engineering efficient heterogeneous catalysts of PET recycling technology.

Automated summary

This study explored the catalytic glycolysis of waste PET plastic using metal oxide catalysts supported on alumina. The basicity of the catalyst was found to be correlated with the glycolysis performances. Among the catalysts tested, 10%Ce/Al2O3 exhibited the highest conversion of waste PET with the highest selectivity to the main product BHET. The catalytic activity remained stable after five consecutive runs, and the quality of the monomer product BHET was confirmed to be excellent. This work contributes to the development of efficient heterogeneous catalysts for PET recycling technology.