Depolymerization of polyurethane foam using Ru/Al2O3 heterogeneous catalysts

This work demonstrates an efficient route for the catalytic chemical recycling of consumer-grade polyurethane (PU) foam via combined ethanolysis and hydrogenolysis over a Ru/Al₂O₃ catalyst. The process enables selective depolymerisation of highly cross-linked PU networks into valuable monomers, including linear carboxylic diethyl esters, glycols, and N-alkylated aromatic diamines, achieving up to 85 wt% cumulative monomer yield (225 °C, 10 bar H₂, 17 h). The study highlights the essential role of Ru/Al₂O₃ in promoting synergistic solvolysis–hydrogenolysis pathways, offering a promising circular alternative to landfill disposal and advancing catalytic strategies for PU upcycling.