title: Decoupling HZSM-5 catalyst activity from deactivation during upgrading of pyrolysis oil vapors.
abstract: The independent evaluation of catalyst activity and stability during the catalytic pyrolysis of biomass is challenging because of the nature of the reaction system and rapid catalyst deactivation that force the use of excess catalyst. In this contribution we use a modified pyroprobe system in which pulses of pyrolysis vapors are converted over a series of HZSM-5 catalysts in a separate fixed-bed reactor controlled independently. Both the reactor-bed temperature and the Si/Al ratio of the zeolite are varied to evaluate catalyst activity and deactivation rates independently both on a constant surface area and constant acid site basis. Results show that there is an optimum catalyst-bed temperature for the production of aromatics, above which the production of light gases increases and that of aromatics decrease. Zeolites with lower Si/Al ratios give comparable initial rates for aromatics production, but far more rapid catalyst deactivation rates than those with higher Si/Al ratios.
authors.affiliation: School of Chemical, Biological and Materials Engineering, University of Oklahoma, 100 E. Boyd St., Room T301 Norman, OK, 73019 (USA).
authors.forename: Shaolong
authors.initials: S
authors.lastname: Wan
authors.forename: Christopher
authors.initials: C
authors.lastname: Waters
authors.forename: Adam
authors.initials: A
authors.lastname: Stevens
authors.forename: Abhishek
authors.initials: A
authors.lastname: Gumidyala
authors.forename: Rolf
authors.initials: R
authors.lastname: Jentoft
authors.forename: Lance
authors.initials: L
authors.lastname: Lobban
authors.forename: Daniel
authors.initials: D
authors.lastname: Resasco
authors.forename: Richard
authors.initials: R
authors.lastname: Mallinson
authors.forename: Steven
authors.initials: S
authors.lastname: Crossley
mesh_terms: D018533:Biomass; D002384:Catalysis; D010578:Petroleum; D013696:Temperature; D014835:Volatilization; D017641:Zeolites / Q000737:chemistry*
chemical_list: D010578:Petroleum; D017641:Zeolites
keywords: aluminum; biomass; heterogeneous catalysis; sustainable chemistry; zeolites