Hydrotreatment and Compound Identification of Distillate Bio-crude Fractions from Continuous Hydrothermal Liquefaction of Wood

Transcription

1 Hydrotreatment and Compound Identification of Distillate Bio-crude Fractions from Continuous Hydrothermal Liquefaction of Wood Claus Uhrenholt Jensen Steeper Energy ApS & Aalborg University Denmark

2 Motivation HTL enables feedstock flexible processing of wet biomass Reaction medium is water at alkaline and supercritical conditions High quality bio-crude: Oxygen below 10wt% HHV above 38 MJ/kg TAN below 25 Mg KOH/g Subsequent deoxygenation to produce bio-fuels or bio-chemicals from lignocellulosic biomass 2

3 Continuous Hydrothermal CBS1, Aalborg University, DK Continuous Bench Scale Capacity around 0.5 BPD 400 C and 300 bar Biocrude presented at TC Biomass is: From co-liquefaction of hardwood and glycerol Comparable, but of slightly lower quality compared to Steeper Energy Hydrofaction oil 3

4 15:5 Fractional Distillation of Bio-crude (ASTM D2892) Fraction F1 Boiling point IBP-100 C Yield 1.6 wt.% F C 4.1 wt.% Fractional distillation (ASTM D2892) enables detailed analysis of particular fractions, e.g. heteroatom distribution and yields F C 6.3 wt.% HTL bio-crude is distillable as produced F C 6.0 wt.% Vacuum distillation is important to protect biocrude from thermal degradation F5 F C C 15.3 wt.% 10.3 wt.% Analysis and utilization of large residue fraction has high priority, but left our of current presentation Residue > 350 C 51.8 wt.% 4

5 Analysis of Biocrude Distillates Sulfur and Nitrogen below calibration level wood contains very little S and N H/C ratio a decreasing function of TBP Oxygen rather evenly distributed HHV rather constant due to similar amount of oxygen in all fractions TAN seems to increase as function of TBP 5

6 Compound Identification of Distillates by GC-MS Boiling point IBP-100 C Yield 1.6 wt.% C 4.1 wt.% C 6.3 wt.% C 6.0 wt.% C 15.3 wt.% C 10.3 wt.% Nice separation by distillation Some overlay is expected from ASTM D2892 fractionation

7 GC-MS indicates: Compound Identification of Distillates by GC-MS Boiling point IBP-100 C C Complex mix of oxygenates C 6.3 wt.% Many phenolic and carbonyl functional groups C5 and C6 derivatives from lignocellulosic precursors C 6.0 wt.% (cellulose, hemicellulose and lignin) Similar hydrocarbon backbone -> Deoxygenation C 15.3 wt.% C Yield 1.6 wt.% 4.1 wt.% 10.3 wt.% 3 most abundant compounds by GC-MS

8 Hydrotreatment of Distillate & Crude bio-oil Hydrotreating on pre-activated and stabilized conventional NiMo/Al2O3 catalyst Microbatch conditions: 360 C, bar, 540 NL H2/L biooil, 1.5h and 4h Successful HDO of both crude bio-oil and fractional distillates Repeatability ensured Indication of slow kinetics 8

9 Compound Identification of HTP by GC-MS HTP of 1.5 hours Incomplete HDO Possibly useful as platform bio-chemicals HHV improved from 35.2 to 42.9 MJ/kg HDO of phenols likely to be of slow kinetics HTP of 4 hours Complete HDO Drop-in biofuels (high octane blend) HHV: from 35.2 to 43.2 MJ/kg Indication of paraffin degradation 9

10 Conclusions The Hydrofaction platform enables bulk production of drop-in bio-fuels and biochemicals from lignocellulosic biomass, e.g. wood Oxygen distributed rather evenly as function of TBP Homogenization of complex oxygenates by hydrotreating entire bio-crude or distillates Future Challenges Hydrotreating in continuous reactors enables catalyst evaluation, mass balance, hydrogen consumption, feasibility studies Downstream process design e.g. product separation, conditioning & hydrotreating Extraction of commodity chemicals Appropriate use of residue fraction? FCC? Hydrotreating of entire crude or fractionation before hydrotreating? 10

11 Acknowledgements Steeper Energy: Steen B. Iversen Göran Olofsson Aalborg University: Lasse A. Rosendahl Thomas Helmer Pedersen Jessica Hoffmann Center for BioOils, C3BO Grant # B Aarhus University: Patrick Biller Industrial PhD Grant # B 11