Preparing methane-resistant Ru catalysts via moderate metal-support interactions for polyethylene hydrogenolysis

Polyethylene is the most abundant component of plastic waste. One dominant polyethylene recycling route is metal-catalyzed hydrogenolysis, since it operates at relatively low temperatures and favors formation of high-value liquid alkanes. Ru catalysts exhibit higher hydrogenolysis activity compared to Pt, Pd, Rh, and Ni. Nevertheless, this also brings a high tendency for terminal C–C scission to form low-value methane. Consequently, highly-selective Ru catalysts often require complex syntheses (e.g., site isolation, composite supports). Here, we report that methane-resistant Ru catalysts can be realized through simple, industrially-compatible impregnation via a moderate metal-support interaction. The choice of ZrO 2 strikes a balance: it promotes H 2 spillover to create an H 2 -rich surface beneficial for hydrocarbon fragment hydrogenation while avoiding excessive retention of the fragments that would favor undesirable overcracking. The resulting nano-sized Ru/ZrO 2 achieves 88.4% selectivity to liquids at full conversion—comparable to state-of-the-art systems—while being prepared by industrially-compatible impregnation.