2024 AIChE Annual Meeting

(569fl) Direct Hydrogenolysis of Post-Consumer PET into BTX Using Platinum-Supported Catalyst

Authors

Hong, D. Y. - Presenter, Korea Research Institute of Chemical Technology
Zhang, H., Korea Research Institute of Chemical Technology
Choi, J., Korea Research Institute of Chemical Technology
Kanwal, S., Korea Research Institute of Chemical Technology
The growing usage of polyethylene terephthalate (PET) has resulted in a surge in the amount of waste PET, which accounts for a significant portion of global discarded plastic. To address this challenge, chemical recycling of waste PET into value-added chemicals has obtained considerable attention. Recently, it has been reported that benzene, toluene, and xylene (BTX), which are widely used as commodity chemicals in the petrochemical industry, can be produced from waste PET via a catalytic process. A few studies conducted the direct hydrogenolysis of waste PET, but equivalent amounts of catalysts are required to convert it selectively due to limited catalytic activity. Therefore, it is very important to develop a highly active and selective catalyst for the direct hydrogenolysis of waste PET into BTX.

In the present study, a highly active and selective catalyst is developed with platinum-supported alumina for the direct hydrogenolysis of waste PET into BTX, with a particular focus on enhancing the production of para-xylene, performed in the absence of solvent. The catalytic performances are evaluated in a semi-batch reaction system at elevated hydrogen pressure up to 85 MPa and temperature reaching 290℃ for 12 h. The complete conversion of PET and 77% yield of BTX are achieved with a modest 10 wt.% catalyst loading, and the BTX yield is further enhanced up to 99% with 30 wt.% catalyst loading. To study the role of the platinum, promoter, and support, various characterization techniques such as XRD, TEM, H2-TPR, XANES, and EXAFS are investigated. The reactions are also conducted in various conditions to gain further insight into the reaction pathways for the direct hydrogenolysis over the platinum-supported catalyst.