(613g) High-Quality Biocrude Production from Reactive Catalytic Fast Pyrolysis

High-Quality
Biocrude Production from Reactive Catalytic Fast Pyrolysis

Joseph
Weiner, Phillip Cross, Elliot Reid, Ofei D. Mante, David C. Dayton

RTI
International, Research Triangle Park, NC 27709 USA.

Abstract

          Reactive
catalytic fast pyrolysis (RCFP) is a direct biomass liquefaction process that
yields a low-oxygen content hydrocarbon-rich biocrude which can be hydrotreated
to produce advanced biofuel (gasoline and diesel).  The process is operated under a reducing
atmosphere, hydrogen gas, which drives further catalytic hydrodeoxygenation of
the pyrolysis vapors to reduce biocrude oxygen content and inhibit char
formation. The lower oxygen content biocrude is more thermally stable compared
to bio-oil produced from conventional non-catalytic, thermal pyrolysis.  Lower char yields also translate into higher
biocrude yield, of the integrated RCFP process, from feedstock conversion to
upgraded biofuels, is being evaluated by RTI to demonstrate the technical
feasibility and economic viability of this advanced biofuels pathway.

          An extended
experimental campaign is currently being conducted to generate enough biocrude
(~3 gallons) from the RCFP process for hydrotreating studies. During this
campaign process conditions have been optimized and catalyst deactivation
behavior has been studied in detail. Dried loblolly pine with a particle size
distribution between 160-500 µm is fed into a laboratory-scale (2.5” diameter)
bubbling fluidized bed reactor containing a commercially-available
molybdenum-based catalyst maintained at 500°C in a large excess of hydrogen.   Pyrolytic vapors are collected in a condensation
train that includes a heat exchanger, a series of impingers, and an electrostatic
precipitator.  The biocrude is collected
and analyzed using GCMS, TGA, and elemental analysis. An online micro GC is
used to measure the composition of the permanent gases. Biocrude oxygen
contents of less than 10% have been measured by the lab-scale system used at
RTI.¹Material and element balances for the RCFP process
and detailed biocrude compositions will be presented. Insights into catalyst
deactivation mechanisms and long-term catalyst performance will be also be
presented. Preliminary results for RCFP biocrude upgrading will be compared to
previous results presented in the literature.²

Keywords:
bioproducts,
reactive catalytic pyrolysis, hydrotreatment, biofuel

References:

1)      K.
Wang, D. Dayton, J. Peters, O. Mante, Green
Chem., 2017, 19, 3243-3251.

2)      Mante,
O. D., D. C. Dayton, J. Gabrielsen, N. L. Ammitzboll, D. Barbee, S. Verdier, K.
Wang Green Chem., 2016, 18, 6123-6135.