On the metal- and bio-catalyzed solvolysis of polyesters and polyurethanes wastes

Catalysis is a crucial tool to efficiently address the recycling and upgrading of polymeric waste within the context of a circular economy, providing affordable and selective methods for waste valorization in alignment with the principles of green chemistry. Various catalysts, including metals, metal–organic frameworks, and biocatalysts, have been explored for the degradation of chemical poly(ethylene terephthalate) (PET) and polyurethane (PU) waste through processes like hydrolysis or alcoholysis. This critical review specifically focuses on catalytic tools, examining both homogeneous systems (such as metal salts or coordination organometallic complexes) and heterogeneous systems where the catalysts are immobilized on solids, including metal oxides, layered or porous solids, or inorganic–organic coordination polymers as well as biocatalytic counterparts from 2017 to the present. We provide a comparative analysis of the chemo-catalysts researched, evaluating their performance relative to biocatalysts using a SWOT analysis of both technologies to highlight their strengths and limitations in the context of sustainable waste management practices.