One-pot Upcycling of Waste Plastics for Selective Hydrogen Production at Low-Temperature

Abstract

Towards global efforts for efficient and sustainable ways to utilize polyethylene terephthalate (PET)-based plastic waste, herein we report an integrated process for the complete one-pot transformation of PET-based plastic waste for hydrogen gas production in an alkaline aqueous condition over a heterogeneous ruthenium catalyst at low temperature (110-160 °C). We could achieve complete selectivity with a high yield of H2 gas (∼38,000 mL H2/gPET/gRu) without any traces of CO and CO2 contaminations. Complete depolymerization of different types of PET-based plastic waste was also achieved with high carbon yield (∼98 %) for disodium terephthalate (Na2TPA, 5.2 mmol/gPET) and sodium formate (SF, 9.6 mmol/gPET), along with H2 gas. Moreover, the developed process is scalable to bulk-level production of hydrogen gas from PET-based plastic waste, highlighting the potential application of the developed process.