- 1. Continuous deoxygenation of cellulose pyrolysis vapors in a
staged autothermal reactor Nils Persson, Samuel Blass, Corey
Rosenthal, Aditya Bhan, and Lanny Schmidt Department of Chemical
Engineering and Materials Science University of Minnesota Twin
Cities
2. Stage 1: Catalytic Partial Oxidation (CPO) of solid cellulose
Stage 2: bifunctional ZSM-5/Pt catalyzed deoxygenation High
throughput, autothermal, small scale Process Summary Integrated
Partial Oxidation and Upgrading Fuel + O2 + Co-feed Pt Catalyst
Oxidation + Pyrolysis Products Bifunctional zeolite Deoxygenated
hydrocarbons 3. Reactive flash volatilization (video) 4. 4 Reactor
HeatChemistry Fuel + O2 + Co-feed Catalyst Endothermic Exothermic
Endothermic Conduction Convection impact melting volatilizationno
char residue Oxidation + Pyrolysis Products Reactive flash
volatilization of solid feedstocks J.L. Colby, P.J. Dauenhauer,
Green Chem., 2008,10, 773-783 5. Cellulose Feed Grain hopper Auger
N2 H2 Mounted electrical connection Relief valve O2 Pt/-Al2O31.3mm
spheres CPO Stage700 C Atmospheric pressure Hydrogen co-feed for
temperature control ~ 3.5 Standard Liters per Minute total gas flow
rate GHSV = 75,000 h-1 9.5 g/h solid cellulose flow rate WHSV =
4.75 h-1 Effluent gases to gas chromatograph (GC) Apparatus Solid
feedstock introduces challenges 6. Pt/-Al2O31.3 mmspheres H2 O2 2
SLPM N2 9.5 g/hr cellulose 0% 20% 40% 60% 80% 100% CO CO2 C1 C2 C3
Oxygenates FirstStage Carbon Yield First stage product
distribution: predominantly oxygenates 7. Pt/-Al2O31.3 mmspheres H2
O2 2 SLPM N2 9.5 g/hr cellulose 0% 20% 40% 60% 80% 100% CO CO2 C1
C2 C3 Oxygenates Aldehydes Furans Acids Ketones Carbon Yield First
stage product distribution: predominantly oxygenates FirstStage
Levoglucosan 8. Cellulose Feed Grain hopper Auger N2 H2 Mounted
electrical connection Relief valve O2 Pt/-Al2O31.3mm spheres CPO
Stage700 C Apparatus Addition of second zeolite stage Use latent
process heat to drive downstream reactions skip bio-oil Zeolite
upgrading: HZSM-5, USY, HFER Bifunctional zeolite/Pt 9. Cellulose
Feed Auger N2 H2 Relief valve Pt/-Al2O3HZSM-5 Zeolite stageHeating
tape O2 Pt/-Al2O31.3mm spheres CPO Stage700 C 500 C Grain hopper
Mounted electrical connection Use latent process heat to drive
downstream reactions skip bio-oil Zeolite upgrading: HZSM-5, USY,
HFER Bifunctional zeolite/Pt Apparatus Addition of second zeolite
stage 10. Pt/-Al2O31.3 mmspheres H2 O2 2 SLPM N2 9.5 g/hr cellulose
0% 20% 40% 60% 80% 100% CO CO2 C1 C2 C3 Oxygenates Carbon Yield
Second stage deoxygenates incoming pyrolysis vapors FirstStage 11.
Pt/-Al2O31.3 mmspheres H2 Pt/-Al2O3HZSM-5O2 2 SLPM N2 9.5 g/hr
cellulose 0% 20% 40% 60% 80% 100% CO CO2 0% 20% 40% 60% 80% 100% CO
CO2 C1 C2 C3 Oxygenates C1 C2 C3 C4 Aromatics Mass balance closes
SecondStage Carbon Yield FirstStage Second stage deoxygenates
incoming pyrolysis vapors 12. Pt/-Al2O3 1.3 mm spheres H2 O2 N2,
cellulose 0% 20% 40% 60% 80% 100% FirstStage Overall Carbon Yield
SecondStage 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% HZSM- 5/Pt
HZSM-5 Pt/- Al2O3 -Al2O3 Pyrolysis Vapor Carbon Yield CO CO2 CH4 C2
- C4 Aromatics Oxygenates Bifunctional HZSM-5/Pt combines
individual functionalities 13. H2 O2 N2, cellulose SecondStage
Methane is hydrogenolysis or methanation (Pt-catalyzed) product
Aromatics are zeolite product Bi-functional catalyst exhibits
compromise in behavior 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
HZSM- 5/Pt HZSM-5 Pt/- Al2O3 -Al2O3 Pyrolysis Vapor Carbon Yield CO
CO2 CH4 C2 - C4 Aromatics Oxygenates Bifunctional HZSM-5/Pt
combines individual functionalities 14. Bifunctional catalysts
resist deactivation and coke formation HZSM-5/Pt: ~ 3% carbon yield
to coke after 60 min. on stream (quantified by burn-off and by
weight) No reactor plugging with solid coke formation 0 10 20 30 40
50 60 CarbonYieldtoOxygenates(%) 5 30Minutes on stream: 15.
Decarbonylation appears to be predominant pathway for deoxygenation
Short bed: C2-C4 are olefins Long bed: C2-C4 are paraffins Possible
hydrogenation of coke precursors 50% oxygenates HZSM-5 / Pt bed
length study decarbonylation predominates 16. Flash volatilization
of solid feedstock Heat integration of millisecond pyrolysis with
downstream zeolite upgrading High throughput, autothermal, small
scale Process Summary Fuel + O2 + Co-feed CPO Catalyst Oxidation +
Decomposition Products Bifunctional zeolite Deoxygenated
hydrocarbons 17. National Science Foundation EFRI: Hydrocarbons
from Biomass Bill Gruhlke Acknowledgements