Abstract
Plastics waste has become a major environmental threat, with polyethylene being one of the most produced and hardest to recycle plastics. Hydrogenolysis is potentially the most viable catalytic technology for recycling. Ruthenium (Ru) is one of the most active hydrogenolysis catalysts but yields too much methane. Here we introduce ruthenium supported on tungstated zirconia (Ru-WZr) for hydrogenolysis of low-density polyethylene (LDPE). We show that the Ru-WZr catalysts suppress methane formation and produce a product distribution in the diesel and wax/lubricant base-oil range unattainable by Ru-Zr and other Ru-supported catalysts. Importantly, the enhanced performance is showcased for real-world, single-use LDPE consumables. Reactivity studies combined with characterization and density functional theory calculations reveal that highly dispersed (WOx)n clusters store H as surface hydroxyls by spillover. We correlate this hydrogen storage mechanism with hydrogenation and desorption of long alkyl intermediates that would otherwise undergo further C-C scission to produce methane.
Original language | English (US) |
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Pages (from-to) | 1422-1434 |
Number of pages | 13 |
Journal | JACS Au |
Volume | 1 |
Issue number | 9 |
DOIs | |
State | Published - Sep 27 2021 |
Keywords
- hydrogen spillover
- hydrogenolysis
- low-density polyethylene
- plastic waste
- ruthenium
- tungstated zirconia
ASJC Scopus subject areas
- Analytical Chemistry
- Chemistry (miscellaneous)
- Physical and Theoretical Chemistry
- Organic Chemistry