Biogas Reforming

MSU Biogas to Liquid Fuel System

Reaction Conditions:

T = 200-350°C,

Gas flow rate =

50~300 mL/min,

P= 500~1000 psi,

Catalyst: 3 grams

Oil Phase

Water Phase

Liquid Sample Reactor System

Syngas containing 50 % H2, 42 % CO, 2% CH4, 1 % CO2, and 5% N2.

Calculation of Conversion / Selectivity

N2 in the syngas was chosen as internal standard for CO conversion calculation The CO

conversion and hydrocarbon selectivity were calculated according to Eqs. (1) and (2),

respectively, where F0 and F are the flow rates of the syngas and effluent gas after the reaction,

respectively, Ci0and Ci are the concentrations of component i in the syngas and effluent gas, and

n is the carbon number in a product i molecular.

Agilent 6890 GC-MS On-line Agilent 6890 gas

chromatograph system

Sample Analysis

Perkin Elmer Clarus

680 GC

Acknowledgement Funding for this work was provided by the U.S. Department of Energy under Grant DOE-DE-FG36-06GO86025 and

DE-FC2608NT01923. The assistance of Ms. Amanda Lawrence of the Electron Microscope Center at Mississippi

State University is gratefully acknowledged.

A continuous process includes reforming, syngas cleaning, and Fischer–Tropsch (FT)

synthesis was developed and evaluated to demonstrate biogas-to-liquid (BTL) hydrocarbon fuel

technology.

Biogas was first dry reformed to syngas over a home-built reformer.

A purification reaction system was designed to remove the impurities in the syngas, i.e.,

moisture, sulfur, and ammonia etc.

A multi-functional cobalt-based catalyst was developed and tested for catalytic converting

syngas to liquid fuels. The Fischer-Tropsch diesel fuel was found with the distillate boils in a wider range of 125 to 365 C, 83.4% (mass) of the liquid fuel is C11-C19 products.

Summary GC-MS of oil phase from wood chips

derived syngas.

Gas phase: On-line Agilent 6890 GC with TCD/TCD/FID.

Liquid samples: A Perkin Elmer Clarus 680 GC with a FID using ASTM D 5134-92 method.

Limited to compounds with carbon numbers less than 14. Another Agilent 6890 GC–MS is also

used for liquid sample analysis (qualitative).

Distillation of the syncrude was performed following ASTM-D86; flash point was tested according

to ASTM-D93.

Catalytic Conversion Syngas to

Liquid Fuels

INTEGRATED REFORMING, SYNGAS CONDITIONING AND CATALYTIC

CONVERSION PROCESS FOR BIOGAS TO WIDE-CUT DIESEL PRODUCTION

Qiangu Yan, Jason Street, Eugene Columbus, and Fei Yu*

Catalyst Gasoline

(C4-C10)

(%)

Wide cut

diesel (C11-

C19) (%)

Waxes (C20+)

(%)

10%Co/Al2O3 5.3 82.1 12.6

10%Co-

5%Mo/Al2O3

10.9 81.8 7.3

2%Pd-10%Co-

5%Mo/Al2O3

6.1 83.4 10.5

Liquid hydrocarbon product (C5+) distribution for

Co/Al2O3 , Co-Mo/Al2O3 , and Pd-Co-Mo/ Al2O3

catalysts.

* Catalyst tests performed at 270 C, 1000 psig, 2000 h-1, and wood syngas, 48 h on stream.

Catalyst Co-Mo Pd-Co-

Mo

Co

Specific gravity at 15 C

(Kg/m3)

825 832 840

Flash point ( C) 59 83 95

Average Molecular Weight 145.5 170.6 183.6

Total Oxygen Content (mass

%)

0.343 0.044 0.015

Total aromatics 21 18 12

Distillation ASTM D 86, °C

IBP 86 125 138

5 116 156 172

10 128 166 183

15 139 177 195

20 149 189 208

30 170 210 229

40 190 232 250

50 208 251 270

60 224 267 288

70 241 285 303

80 258 300 319

85 268 311 330

90 280 324 340

95 297 345 390

FBP 320 365 410

Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, MS, USA Corresponding Author. Tel: +1 662-325-0206; Fax: +1 662-325-3853; E-mail: fyu@abe.msstate.edu.

Characterization of liquid fuels from syngas

Temp

(ºC)

CO

Conversi

on

(mol%)

CO2

selectivit

y

(mol%)

Hydrocarbon selectivity

(mol%)

C1 C2 C3 C4 C5+

230 42.3 8.0 4.7 1.3 0.8 1.9 83.3

250 49.8 8.4 5.0 1.5 1.3 2.1 81.7

270 54.9 9.2 5.2 2.0 1.5 2.3 79.8

290 57.4 9.5 5.1 2.1 2.5 2.8 78.0

310 65.6 9.9 5.5 3.0 2.8 3.2 75.6

330 67.2 10.3 5.7 2.9 3.1 3.5 75.2

Tem

p

(ºC)

CO

Conver

sion

(mol%)

CO2

selecti

vity

(mol%)

Hydrocarbon selectivity

(mol%)

C1 C2 C3 C4 C5+

230 45.5 8.3 4.2 1.5 0.5 1.3 84.2

250 53.3 8.6 4.5 1.6 0.8 1.9 82.6

270 59.5 9.7 4.9 1.9 1.1 2.7 79.7

290 64.8 10.2 5.3 2.3 1.5 2.9 77.8

310 71.2 10.5 5.6 2.5 2.0 3.6 75.8

330 73.3 11.7 6.5 2.6 2.1 3.8 73.3

Temp

(ºC)

CO

Convers

ion

(mol%)

CO2

selectivi

ty

(mol%)

Hydrocarbon

selectivity

(mol%)

C1 C2 C3 C4 C5+

230 55.1 7.1 3.9 0.8 0.5 1.4 86.3

250 60.5 7.5 4.1 1.1 0.8 2.3 84.2

270 69.4 7.8 4.5 1.3 0.9 2.6 82.9

290 72.8 8.3 5.2 1.9 1.3 2.9 80.4

310 77.3 8.5 5.3 2.3 1.8 3.5 78.6

330 80.2 8.7 5.5 2.8 2.1 3.9 77.0

Syngas Cleaning

Lab scale Pilot scale

Syngas cleaning for removing

ammonia, and sulfur etc.

Components NH3 H2S + COS

Before Cleaning 200-1000 200-400 ppm

After Cleaning <1ppm <10ppb

Impurities identified from bio-syngas before and

after cleaning.

CO conversion, CO2 and hydrocarbon selectivity

over the 10% Co/Al2O3 for the FTS process*

•Catalyst tests performed at 6.7MPa, 2000 h-1, and woody syngas, 48 h on stream..

CO conversion, CO2 and hydrocarbon selectivity

over the Co-Mo/Al2O3 for the FTS process*

CO conversion, CO2 and hydrocarbon selectivity

over the Pd-Co-Mo/Al2O3 for the FTS process*

•Catalyst tests performed at 6.7MPa, 2000 h-1, and woody syngas, 48 h on stream..

•Catalyst tests performed at 6.7MPa, 2000 h-1, and wood syngas, 48 h on stream..

FT Catalytic Performance

Time of stream of CO conversion, light

hydrocarbon and liquid product selectivity

on the catalyst at 310oC and 1000 psi

over the Pd-Co-Mo/Al2O3 .

Typical properties of synthetic fuels from syngas.

Temperature( C) H2 (%) CO (%) N2 (%) CH4 (%) CO2 (%) H2/CO

750 48.96 40.82 6.33 1.75 2.01 1.2

775 49.45 41.22 6.27 1.3 1.74 1.2

800 50.06 42.2 6.05 0.96 1.12 1.19

825 50.57 42.7 6.03 0.57 0.78 1.18

850 50.75 43.11 5.93 0.4 0.25 1.18

Product gas composition for simultaneous dry and partial oxidation of biogas

(Biogas feedstock: 60% CH4, 40% CO2; reforming reaction over a Ni/ -Al2O3 catalyst at

8000 h-1GHSV and O2/CH4 ratio of 1/6 under atmospheric pressure.)

Effect of O2/CH4 ratio on the catalyst performance (Biogas

feedstock: 60% CH4, 40% CO2; reforming reaction over a Ni/ -

Al2O3 catalyst at 8000 h-1GHSV under atmospheric pressure).

SEM images of a Ni-based catalyst samples

Fresh Used

H2-TPR results of the Ni-based catalyst samples.

Temperature-programmed methane dry reforming over Ni-based catalysts: catalyst #1 (left) and Catalyst #2 (right).

SYNGAS PRODUCTION

HYDROCRACKING

FISCHER-TROPSCH SYNTHESIS

Gasoline, Diesel

Natural Gas/Biogas