Mariefel V. Olarte, Asanga B. PadmaperumaPacific Northwest National Laboratory

Jack Ferrell, Earl D. ChristensenNational Renewable Energy Laboratory

Analysis of distillate fractions from hydroprocessing of oak pyrolysis oil

Biomass as liquid fuel

• Biomass – considered as the most accessible source of

renewable liquid transportation fuel

2

Zacher, et al. 2014. Green Chem. 16: 491

Can we optimize the degree of deoxygenation?

Upgraded oil characteristics

• What is the effect of the final oxygen content on the characteristics of the oil fractions?

• How is the heteroatom distribution (O, S, N) affected?

3

Answers impact:• Techno-economic analysis• Product specifications acceptability• Processing decisions

Landmark Paper: Christensen, et. al., 2011

4

Low O

Content

Medium O

Content

High O

Content

Distillation

Lights

Naphtha

Jet

Diesel

Gas oil

Solid

Lights

Naphtha

Jet

Diesel

Gas oil

Solid

Lights

Naphtha

Jet

Diesel

Gas oil

SolidMix multiple HT runs

A

N

A

L

Y

S

I

S

Upgraded

product A

Upgraded

product B

Upgraded

product C

….

Christensen, E., et al. (2011), Energy & Fuels, 25, 5462-5471.

What was available…

Need to revisit: The sulfur question

High S content seem to contradict:

• Woody bio-oil selling point: generally has less S than crude oil.

• Elemental analysis of recently upgraded oils typically report less than 0.03 wt% S.

Current approach

6

Oak

pyrolysis oil

Distillation

Sulfided

catalyst HT

Non-sulfided

catalyst HT

Fraction 1

Fraction 2

Fraction 3

Fraction 4*

Fraction 5*

Fraction 1

Fraction 2

Fraction 3

Fraction 4*

Fraction 5*

A

N

A

L

Y

S

I

S

1.84 wt% O

(composite)

5.87 wt% O

(composite)

• 2 runs in the 60 mL reactor to produce

needed quantity for distillation

• RuS/C and commercial HT catalyst

Pre-

treatment

• 400 mL reactor

• Ru/C and Pd/C

Mix timed samples* Under vacuum

- Single bio-oil feed, targeted oxygen content

- Use of vacuum at high temperatureLOC

MOC

Fast Pyrolysis Unit

7

NREL’s TCPDU run conditions• N2 carrier gas flow rate = 20 kg/h

• Biomass feed rate = 10 kg/h

• Superheater T = 400°C

• Reactor T = 500°C

• Eductor P (SP) = 50 kPa

• Heat Trace T = 500°C

Baldwin & Feik. Energy & Fuels. 2013. 27: 3224-3238

Hydroprocessing Units

8

30/60 ml dual T

zone packed bed

reactor

400 /900 ml dual T

zone packed bed

reactors

Ru/CRu/C

Pd/CComml

HT cat

RuS/C

T = 140-170°CP = 1200 psigLHSV = 0.5 ml bio-oil/

ml catalyst-hr

T1 = 170-190°CT2 = 400°CP = 1800 psigLHSV = 0.22 ml bio-oil/

ml catalyst-hr(per bed)

T1 = 170-190°CT2 = 395-405°CP = 2000 psigLHSV = 0.28 ml bio-oil/

ml catalyst-hr(per bed)

Elliott, D.C., et. al. (2009). Env Prog & Sust Energy, 28 (3), 441-449.

Zacher, A. (2014). Green Chem .16 (2), 491-515

Liquid streams characterization

9

Oak Pyrolysis

oilPre-treated oil MOC composite oil

LOC

composite

oil

Carbon (D5373/D5291), dry wt% 45.2 56.92 81.88 84.91

Hydrogen (D5373/D5291), dry wt% 7.09 6.72 12.25 13.26

Nitrogen (D5373/D5291), dry wt% 0.07 0.07 <0.05 <0.05

Oxygen (D5373 mod), dry wt% 47.7 36.34 5.87 1.84

Sulfur (D4239/D1552), ppm <0.02 <0.02 <0.03 <0.02

O/C molar ratio 0.79 0.48 0.05 0.02

H/C molar ratio 1.88 1.42 1.80 1.87

Water content (KF, ASTM D6869), % 19.1 20.4 0.6 <0.3

Total acid number (TAN, ASTM D3339), mg

KOH/g oil106.9 109.7 39.29 <0.01

Density, g/cc 1.24 (40°C) 1.23 (40°C) 0.87 (20°C) 0.83 (20°C)

Viscosity, mm2/s 114 (40°C) 161 (40°C) 2.7 (20°C) 1.8 (20°C)

Simulated distillation of composite

LOC MOC

BP Range Frxn # SimDist SimDist

0-150 1 34% 28%

150-184 2 9% 11%

184-250 3 16% 18%

250-338 4 20% 27%

>338 5 20% 16%

� SimDist of composites

� LOC and MOC boiling ranges encompass multiple petroleum blend stock

ranges

Fractionation of upgraded oils

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Fraction 1 20°C-150°C, atmospheric

Fraction 2 150°C-184°C, atmospheric

Fraction 3 184°C-250°C, atmospheric

Fraction 4 250°C-338°C (atm.), vacuum applied (107°C-198°C @ 6 mmHg)

Fraction 5 >340°C (atm.), vacuum applied (>198°C @ 6 mmHg)

Distillation cut-off points for LOC and MOC oils

Simulated distillation of fractions

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� MOC fraction 1 falls within BP requirements for gasoline – however, other considerations exist

� Fraction 3 falls within jet BP

� Fraction 4 falls within diesel BP

PIONA Analysis: Fraction 1

LOC LOC LOC LOC MOC MOC MOC MOC FCC naphtha*FCC naphtha*FCC naphtha*FCC naphtha*

ParaffinParaffinParaffinParaffin 44.4 12.9 3.75 - 5.38

IIII----ParaffinsParaffinsParaffinsParaffins 14.0 12.7 20.11 - 35.65

AromaticsAromaticsAromaticsAromatics 2.8 2.1 4.28 - 36.99

NaphthenesNaphthenesNaphthenesNaphthenes 36.7 43.9 5.76 - 9.57

OlefinsOlefinsOlefinsOlefins 1.6 1.9 32.11 - 48.93

UnidentifiedUnidentifiedUnidentifiedUnidentified 0.5 14.6 -

BenzeneBenzeneBenzeneBenzene 0.5 0.1 -

RONRONRONRON 65 78 -

MONMONMONMON 60 59 -

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� Fraction 1 boiling point range falls within gasoline requirement� Research and motor octane numbers (RON and MON) are low

*Hudebine, D. and Verstraete, J.J. (2011), Oil & Gas Sci Technol, 66, 437-460.

Total Acid Number

TAN (ALS) TAN (PNNL)

LOC frxn 1 <0.01 0

LOC frxn 2 <0.01 0

LOC frxn 3 <0.01 0

LOC frxn 4 <0.01 0

LOC frxn 5 <0.01 0

MOC frxn 1 55.31 51.2

MOC frxn 2 116.62 122.6

MOC frxn 3 39.44 41.9

MOC frxn 4 4.77 5.1

MOC frxn 5 0.3 0

� Only MOC has measurable TAN

Elemental Analysis� For LOC:

� ↑ C, ↓ H as ↑ BP of fraction� Almost same O content� ↓ H/C – more unsaturation

~ aromatics� Highest S in Fraction 1� Negligible N

15

� For MOC:

� ↑ C, ↓ H as ↑ BP of fraction but H decrease not as dramatic

� ↓ O content

� Lowest S in Fraction 1

� Highest N in heaviest fraction

Recalcitrant S present and similar trend in fractions irregardless of catalyst used; except for Fraction 1

van Krevelen Chart

16

� For LOC (O = 1.84 wt%), H/C decreasing

� For MOC (O = 5.87 wt%), H/C and O/C follows a linear trend

� LOC and MOC oils compared to other oils

Oxygenated compounds: Acids and phenols

� Only found in fractions 1 to 3

� LOC has phenols

� MOC has acids and phenols

� Acid: valeric acids (n + iso) > butyric acid > acetic acid

� Phenol: o-cresol

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� Found in fractions 1 to 5

� Benzaldehyde > butyraldehyde > 2,5-dimethylbenzaldehyde

Oxygenated compounds: Aldehydes

Conclusions

• Presented a comprehensive analysis of distillates with two composite O content from a single source

• Difference in S distribution was found to be only at the lightest fraction

• May impact sulfur management

• Determining the effect of oxygenates on fuel blends is an important research effort

• Fractions may be within SimDist boiling point ranges but may have oxygenates present that can affect specification acceptability

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Acknowledgements

PNNL� Analysis Team

• Rich Hallen

• Rich Lucke

• Sarah Burton

• Teresa Lemmon

• Marie Swita

• Heather Job

• Beth Hofstad

• Juan Lopez Ruiz

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� Hydroprocessing Team

• Gary Neuenschwander

• Leslie Rotness

• Miki Santosa

• Craig Lukins

• Igor Kutnyakov

� Discussion/Insight

• Corinne Drennan

• Alan Zacher

• Doug C. Elliott

NREL

� Gina Chupka

Thank you for listening!

Funding : US DOE BETO