Prof. Jonggeol Na of Ewha Womans University and Prof. Hyeong Jun Kim of Sogang University have jointly developed recoverable solid bead catalysts that can be repeatedly reused in the chemical recycling of PET. The study presents a new approach to simplifying the complex catalyst separation and purification processes used in conventional PET recycling.
The research team designed bead-shaped solid catalysts that can be easily recovered through simple filtration after the reaction. Their interconnected porous structure allows reactants to penetrate into the interior of the beads, achieving more than 99% PET depolymerization and a maximum BHET yield of 96.9%. The catalysts also maintained an average BHET yield of 90.7% and 89% of their initial weight after 30 reuse cycles.
By introducing recoverable catalysts, the conventional repeated recrystallization process could be replaced with a two-step evaporation process using the difference in boiling points between BHET and ethylene glycol. The research team estimated that the resulting process could produce BHET at a minimum selling price of $1.02 per kg, while greenhouse gas emissions from recycled PET production were estimated at 1.90 kg CO₂ per kg of PET. The study was published in Nature Communications and supported by the National Research Laboratory (NRL 2.0) Program through IMMS, among other research programs.
IMMS will continue to expand interdisciplinary research on plastic resource circulation and sustainable materials and processes, fostering collaborative research that addresses major industrial and societal challenges.
Related Link
Read the Ewha News Article (EN): A Catalyst You Can Filter Out — and Use Thirty Times Over
