Conversion of Bio-oil to

Hydrocarbons Via a Low Hydrogen Route

Philip H. Steele and Sathish K. Tanneru

Forest Products Department

Mississippi State University

1

Pyrolysis auger reactor:

• MSU has developed a 7 kg/h auger fast pyrolysis reactor to produce bio-oil from biomass. Bio-oil yields are 65% from pine wood. Pine wood bio-oil was utilized in our experiments.

2

Bio-oil properties:

40-50% oxygen content is the primary factor causing

the negative properties of bio-oil:

• High acidity

• Aging problem (polymerization)

• Immiscibility with petroleum-derived fuels

• Pungent odor

• Low energy density (35 – 40% petroleum fuels)

3

Alternate bio-oil hydroprocessing methods to produce hydrocarbons:

100% H2 or

bio-syngas*

Pretreated

bio-oil

*Patent pending

4

Hydrotreating via

HT

bio-oil

Hydrocracking

via 100%

H2

Hydrotreating bio-oil with syngas:

• MSU has developed a technique (patent pending) utilizing a proprietary bio-oil pretreatment process.

• This pretreated bio-oil allows hydrotreating (HT) with syngas containing 18% vs 100% H2. Required HT H2 is produced by the water gas shift reaction (WGS).

• Biomass syngas can be produced near the resource by gasifying biomass not suitable for pyrolysis. This will allow HT near the resource rather than at a centralized methane cracking facility; following HT the bio-oil is stabilized and can then be transported and stored without aging.

5

Materials and Methods: • Raw bio-oil required for this research

was produced from loblolly pine wood

chips in the Department of Forest Products,

MSU.

• The syngas was produced by a down-draft

gasifier and compressed to 1500 psi

in laboratory tanks. We thank Dr. Fei Yu for

supplying this compressed syngas for our

experiments.

• Catalysis was performed with nickel-based proprietary heterogeneous catalysts.

• Hydroprocessing treatments were performed in

a stirred batch autoclave.

6

1st stage hydrotreating (HT) comparing 100%

H2 and syngas results:

Property Raw bio-oil Hydrogen HT

product

Syngas HT

product

Acid value 98.0 55.5 51.6

HHV, MJ/kg 16.1 34.7 36.5

Water, % 30.6 3.1 2.7

C,% 37.99 73.7 76.4

H,% 7.97 9.7 9.1

N,% 0.14 0.3 0.4

O,% 53.6 15.2 14.0

Syngas HT

product

7

Hydrocarbon mix vs diesel properties compared to

both syngas and 100% H2 HT with 100% H2 HC;

there is little diff. between fuel properties: Property Raw bio-

oil

Hydrocarbon

mix H2 HT and

H2 HC

Hydrocarbon

mix syngas

HT and H2 HC

Diesel

Acid

value 98.0 0 0 0

HHV,

MJ/kg 16.1 46.1 45.1 45.8

Yield,% 30 26

Water, % 30.6 0.02 0.08 0

C,% 36.2 86.2 86.6 85.1

H,% 7.8 13.6 13.2 12.2

N,% 0.03 0.14 0.14 0

O,% 56.0 0 0 0 8

Simulated distillation of hydrocarbon

mix produced by syngas HT followed by

100% H2 HC:

9

0

20

40

60

80

100

120

0 50 100 150 200 250 300 350

Yie

ld %

Temperature oC

Diesel, 15% 250-350 oC

Gasoline, 55% 0-170 oC

Jet fuel, 30% 170-250oC

Simulated distillation of hydrocarbon mixture

produced by both 100% H2 HT and HC:

0

10

20

30

40

50

60

70

80

90

100

0 50 100 150 200 250 300

Yie

ld %

Temperature (oC)

Jet fuel, 11% 170-250 oC

Gasoline, 88% 50-170 oC Diesel, 1%

250-350 oC

10

WGS reaction: CO + H2O H2 + CO2 • Syngas HT exit gas

shows the consumption

of 17% CO to produce H2

via the WGS.

• This supplemented the

low 18% of syngas H2;

39% of CO2 (+28%).

• For the 100% H2 HT, exit

gas shows 49% of H2 was

consumed.

• For H2 HC for both

syngas and H2 HT, 21 and

33% of H2 was consumed;

CO2 is low without WGS.

Sample Name Hydrogen% CO% CO2%

Syngas 18.0 22.0 11.0

Syngas HT exit

gas

1.1

5.0

(17.0) 38.8

H2 HT exit gas 51.0 (49.0) 0.6 15.9

H2 HC exit gas

(From Syngas

HT) 79.0 (21.0) 0.0 9.7

H2 HC exit gas

(From H2 HT) 67.0 (33) 0.0 11.4

11

Syngas and reactor

exit gas components

Total H2 consumed using syngas HT vs H2 HT;

both followed by 100% H2 HC:

17% syngas H2 was consumed for HT

21% H2 consumed for H2 HC

39% total H2 consumed

49% H2 consumed for H2 HT

33% H2 consumed for H2 HC

82% total H2 consumed

Therefore, H2 consumption reduced by (82 – 39%)

43% if syngas HT is applied

12

MSSTATE pilot plant 2-t/h fast pyrolysis

auger feed reactor:

Infeed to biomass handling system

for pyrolysis reactor:

Summary:

• MSU has developed a pretreatment method that allows the utilization of syngas for HT of bio-oil.

• The potential of using syngas, rather than hydrogen, for HT was tested. Results show that much of the HT H2 required is supplied by the WGS reaction. H2 consumption was reduced by 43% by use of syngas for the HT step.

• The respective HT intermediate products differed little between syngas treated and H2 treated.

• Likewise, there was little difference between the final H2 HC products whether the HT was performed by syngas or H2.

15

Summary:

• The ratio of hydrocarbon fuel types differed between syngas HT and H2.

• MSU is near completion of fabricating a 2-ton/day pyrolysis pilot plant with biomass feed capability and fuels conversion technology.

16

Acknowledgement:

• This research is based upon work funded through the Sustainable Energy Research Center at Mississippi State University and is supported by the Department of Energy under Award Number DE-FG3606GO86025.

Thank you

17

Conversion of Bio-oil to

Hydrocarbons Via a Low Hydrogen Route

Philip H. Steele and Sathish K. Tanneru

Forest Products Department

Mississippi State University

18

DHA analysis of hydrocarbon mixture

produced by syngas HT and 100% H2 HC and

both 100% H2 for HT and HC:

6.84

17.51

26.9

13.79

7.21

10.04

15.02

2.11

23.38 24.71

20.53

6.69

21

1.55

0

5

10

15

20

25

30

Paraffin

s

I-Paraffin

s

Olefin

s

Nap

thn

es

Aro

matics

Un

kno

wn

s

Total C

14

+

M

a

s

s

%

Class type

Syngas hydrocarbon mix H2 hydrocarbon mix

19

Syngas and reactor exit gas components:

Water gas shift reaction (WGS):

CO + H2O H2 + CO2

• Syngas HT exit gas shows the

consumption of 17% CO to

produce H2 via the WGS

• This supplemented the low 18%

of syngas H2; 39% of CO2was

produced from the WGS

• For the 100% H2 input for HT,

exit gas shows that 49% of H2

was consumed

• For H2 HC for both syngas and

H2 HT, 21 and 33% of H2 was

consumed, respectively; CO2

produced is low without WGS

Sample Name Hydrogen% CO% CO2%

Syngas 18.0 22.0 11.0

Syngas HT exit

gas

1.1 5.0 38.8

H2 HT exit gas 51.0 (49.0) 0.6 15.9

H2 HC exit gas

(From Syngas HT) 79.0 (21.0) 0.0 9.7

H2 HC exit gas

(From H2 HT) 67.0 (33) 0.0 11.4

20

Total H2 consumed using syngas HT vs

H2 HT; both followed by 100% H2 HC:

17% syngas H2 was consumed for HT

21% H2 consumed for H2 HC

39% total H2 consumed

49% H2 consumed for H2 HT

33% H2 consumed for H2 HC

82% total H2 consumed

Therefore, H2 consumption reduced by (82 – 39%)

43% if syngas HT is applied

21

Input of H2

vs H

2

consumed from

that produced by the WGS:

• When 100% H2 was applied for HT, 49% of it was

consumed for the HT reaction. It is probable that less total hydrogen than 49% was produced by the 18% H2 contained in the syngas added to that produced by the WGS. However, the quality of the syngas HT bio-oil indicates that the reaction had adequate hydrogen to produce an HT product quite similar to that produced by 100% H2

HT.

• Evidence that the WGS produced H2 was provided by the high 39% production of CO2 for syngas HT compared to 16% for H2 HT.

Water gas shift reaction (WGS): CO + H2O H2 + CO2

Hydrocarbon mix vs diesel properties produced

with syngas HT and100% H2 hydrocracking (HC):

Property Raw bio-oil Hydrocarbon

mix from 100%

H2 HC

Diesel

Acid value 98.0 0 0

HHV, MJ/kg 16.1 45.1 45.8

Water, % 30.6 0.08 0

C,% 36.2 86.6 85.1

H,% 7.8 13.2 12.2

N,% 0.03 0.15 0

O,% 56.0 0 0

23

Hydrocarbon mix vs diesel properties

produced with both 100% H2 HT and HC:

Property Raw Bio-oil Hydrocarbon

mix

Diesel

Acid value 98.0 0 0

HHV, MJ/kg 16.1 46.1 45.8

Water, % 30.6 0.02 0

C,% 36.2 86.2 85.1

H,% 7.8 13.6 12.2

N,% 0.03 0.14 0

O,% 56.0 0 0

24