Bifunctional tandem catalytic upcycling of polyethylene to surfactant-range alkylaromatics

Scientific Achievement

  • The rates of tandem hydrogenolysis/aromatization of polyethylene and the selectivity to alkylaromatics are greatly enhanced by the synergy between strong Brønsted acid sites and Pt nanoparticles. 
  • Pt is responsible for hydrogenation/dehydrogenation, while Brønsted acid sites convert olefins to carbenium ions that readily undergo skeletal transformations (isomerization, C-C bond scission, cyclization). 

Significance and Impact

  • Bifunctional catalysts improve the viability of chemical upcycling for waste polyolefins to value-added surfactant-range alkylaromatics. 
  • This work also advances quantitative catalyst assessment and product analysis in polyolefin upcycling.

Research Details

  • Pt/F-Al2O3 and physical mixtures of Pt/g-Al2O3 and F-Al2O3 are effective.
  • The rates of C-C bond scission, alkane isomerization, and aromatization all correlate linearly with the total number of strong Brønsted acid sites. 
  • Nanoscale proximity between Pt and acid sites is not required to convert alkanes to alkylaromatics.

Sun et al., Chem 2023, 9, 2318–2336. https://doi.org/10.1016/j.chempr.2023.05.017 

iCOUP is an EFRC, supported by Basic Energy Sciences

Work was performed at UCSB, UIUC and Cornell