Pyrolysis II Proceedings - Gas Technology Institute NonAtmospheric, Non-catalytic Method for...

Pyrolysis II Proceedings

Session Chair: Akwasi Boatang

U.S. Department of Agriculture, Agriculture Research Service

High Yield Process for Hydrocarbon

Fuels from Cellulosic Biomass by

Pyrolysis of Organic Acid Salts

M. Clayton Wheeler

University of Maine

Clayton Wheeler received a Ph.D. in Chemical Engineering from the

University of Texas at Austin in 1997.

He then worked as a research engineer for Texaco in the areas of enhanced

oil recovery and Fisher-Tropsch Gas-to-Liquids technologies. After leaving

Texaco, he received a National Research Council Postdoctoral Fellowship to

conduct catalytic gas sensor research at the National Institute of Standards

and Technology.

He is currently an Associate Professor of Chemical and Biological

Engineering and the Thermal Conversion Group Leader of the University of

Maine’s Forest Bioproducts Research Institute.

The group’s areas of expertise include pyrolysis, catalyst development for

pyrolysis and pyrolysis oil hydrodeoxygenation, ketonization of mixed organic

acids, thermal deoxygenation and hydrogenation.

Atmospheric Non catalytic Method for Atmospheric, Non-catalytic Method for Hydrocarbon Fuels from Cellulosic Biomass b P rol sis of Organic Acid SaltsBiomass by Pyrolysis of Organic Acid Salts

M. Clayton Wheeler, University of MainePaige A. Case, Scott J. Eaton, Adriaan R. P. van Heiningen, and William J. DeSisto

Forest Bioproducts Research InstitutepFBRI Technology Research Center

FBRIChemistry Chem. Bio. Eng.Chemistry

Advanced Composites

Forestry

Biology

Margaret Chase Smith Policy Center

Footer goes here2tcbiomass2011

Overview of Method for Biomass Conversion to Drop-in Hydrocarbon FuelsConversion to Drop-in Hydrocarbon Fuels

High yields of carbohydrate conversion to oilHHV=41MJ/kg<1% Oxygen<1% OxygenTAN = 1 mgKOH/g

Hydrolysis and

Dehydration

Neutralize with Ca(OH)

Pyrolysis

with Ca(OH)2


Removal of Oxygen from Biomass(E l C ll l )(Example: Cellulose)> Hydrodeoxygenation

─ ~81% theoretical energy yield

100% carbon efficiency

OHCHOHCH 2251062 566 +→+

─ 100% carbon efficiency

─ 48% mass efficiency

> Theoretical Decomposition> Theoretical Decomposition

─ ~87% theoretical energy yield2225106 24 COOHCHOHC ++→

─ 67% carbon efficiency

─ 35% mass efficiency


Ketonization of Organic AcidsKetonization of Organic Acids

O

O

O

ΔCa

O

CaCO3+

> Net removal of 1 CO2 and 1 H2O or 1.5 O atoms/acid:─ Slaking

O

( )22 OHCaOHCaO →+g─ Ketonization─ Calcination

> I b h i l th t R1+R2 +1

( ) 3221221 2 CaCOOHCORROHCaCOOHRCOOHR ++→++

23 COCaOCaCO +→

( )22

> Increases carbon chain length to R1+R2 +1> Ketones can be hydrogenated and dehydrated to olefins which

can then be oligomerized to hydrocarbon mixtures


Organic Acids from BiomassOrganic Acids from Biomass

> Acidogenic mixed-culture fermentation (Terrabon)─ Carbohydrates are converted to mixtures of C2 to C7 range

predominately aliphatic acids

> Acid hydrolysis and dehydration (Biofine)> Acid hydrolysis and dehydration (Biofine)─ Cellulose converted to levulinic and formic acids (1:1 ratio)

223855106 OHCOHCOHC +→

─ C5 Hemicellulose (xylan) converted to furfural

223855106


Ketonization of Calcium LevulinateKetonization of Calcium Levulinate450 CO

OH

10

20

Inte

nsity

OO

OH

OH

20 40 600

Retention Time (min)

> Ramp to 450°C with N2 purgeW t l bl d t

T. Schwartz, et al., Green Chem., 2010, 12, 1353–1356.

> Water soluble products> No predicted ketone observed> 35 MJ/kg (calorimetry of extracts)


> 35 MJ/kg (calorimetry of extracts)

Thermal Deoxygenation (TDO)O O

O

Base BaseCa

O

O

OO CaCO3 +

OO

OO

OOH

O OBase Bas

H+ H+

BaseCa

O

O

O CaCO3

O

O

+H2O

O

OH

O

+

H2O

se

Products can be explained by ─ initial Ketonization

O

─ followed by Pyrolysis• Aldol condensation + dehydration


• High-temperature free radical reactions

Thermogravimetric Analysis of Reagent Formate and Levulinate SaltsFormate and Levulinate Salts> Cellulose hydrolyzates contain equimolar levulinate and formate

> Ca(HCOO)2 → CO + H2 + CaCO3( )2 2 3

Virtually no carbon in residue of levulinate/formate mixture!


Formate-Enhanced TDO Produces a H d b OilHydrocarbon Oil

Aqueous +nt

ribut

ion

Aqueous + Gas

arbo

n C

on Oil

Char

% C

a

F i /L li i A id R ti

Char

Carbonate

> Oil contains 82% of theoretical carbon (to 44MJ/kg) and 78% of theoretical mass at Formic/Levulinic = 1/1

Formic/Levulinic Acid Ratio


78% of theoretical mass at Formic/Levulinic 1/1

13C NMR of Oils Indicate Very Low O C t t Oxygen Content


Formate Increases Relative Fraction of U t t d C b i OilUnsaturated Carbons in Oil

70Aromatic/Alkene

50

60

13C

NM

R

Alk l

Aromatic/Alkene

30

40

rbon

s fro

m Alkyl

10

20

% o

f Car

Carbonyl00.0 0.5 1.0 1.5

Formate/Levulinate Mole Ratio


Insignificant Increase of HHV or H/C R ti Ab 5% F tH/C Ratio Above 5% Formate

1.9

44

1.5

1.7

40

42

Rat

io

kg)

H/C

HHV

1.1

1.3

36

38

H/C

Mol

e R

HH

V (M

J/k H/C

0.7

0.9

30

32

34 H

0.5300.0 0.5 1.0 1.5

Formate/Levulinate Mole Ratio


Efficiencies of Carbohydrate Conversiony2225106 24 COOHCHOHC ++→

222485 67.167.0333. COOHCHOHC ++→

Cellulose:Xylan:

Mass Efficiency (%) Energy Efficiency (%) §

Basis Theoretical Actual/Calculated Theoretical Actual/Calculated

Levulinate/Formate1/1 35 27† 87 63

Cellulose 35 19† 87 44Xylan 35 13‡ 89 32Wood* 26 13 59 27

§ HHV(MJ/k ) b(17 5) li i (25) f t il(44) d t l il(41)§ HHV(MJ/kg) = carb(17.5), lignin(25), perfect oil(44), and actual oil(41)† 70% levulinic acid yield, 78% oil yield‡70% furfural yield, 70% conversion to levulinic acid, 78% oil yield


* Ash-free, 50% C6, 25% C5, 25% Lignin

Independent Testing of Washed Crude TDO Oil Produced from Biomass Hydrolyzate

Boiling Point Distribution ( S 69)

Total Acid Number 1.02 mg KOH/gRamsbottom Carbon Residue 0 48 wt%

80

90

100

(ASTM D7169)

OXYGENATES (0.86%) GC Low Ox method (ppm)

Ramsbottom Carbon Residue 0.48 wt%

TRACE METALS

ICP (ppm)

Aluminum <0.1 A i <0 1

50

60

70

80

ecov

ered

Acetaldehyde 43 Methanol 18

Ethanol 53 Propanols 44 n-Butanol 14

Butyraldehyde 16

Arsenic <0.1Barium <0.1

Beryllium <0.1 Bismuth <0.1

Boron <0.1 Cadmium <0 1

10

20

30

40

%R

eButyraldehyde 16 Methyl T-Butyl Ether 24

Ally Alcohol 4 tert-Amyl Alcohol 15

Vinyl Acetate 8338

Cadmium <0.1Calcium 4.5

Chromium <0.1 Cobalt <0.1

Copper 0.4 Iron 8 8

0

10

100 200 300 400 500Boiling Point, °C

Iron 8.8Lead 0.3

Magnesium <0.1 Potassium 0.2

Sodium 0.2


Comparison of Boiling Point DistributionsCrude TDO OilRetorted Oil ShaleOil Sands HGOLight Arabian Crude#2 Diesel

ure

(°F)

Tem

pera

tuT

> ~80% Overlap with #2 dieselRecovery (mass%)


80% Overlap with #2 diesel

PONA Analysis (ASTM D6730)35

30

35

P ffi (2 7%)Calculated PropertiesO t (R+M)/2 81 9

Sub-400°F "Gasoline" Cut (28% of sample)

20

25

cove

red Paraffins (2.7%)

I-Paraffins (30.0%)Olefins (16.8%)Cyclo-Paraffins (19 0%)

Octane, (R+M)/2 = 81.9Specific Gravity = 0.793H/C ratio = 1.75Benzene = 0 8 vol%

15

e %

Rec Cyclo Paraffins (19.0%)

Aromatics (31.5%)Benzene = 0.8 vol%

5

10

Volu

me

03 4 5 6 7 8 9 10 11 12 13 14 15

Carbon Number


Conclusions/ImplicationsConclusions/Implications

> Two-step pathway to fungible hydrocarbon oil (41 MJ/kg)!

> 0.9 BOE / ODMT Wood demonstrated (1.9 BOE potential)

> Atmospheric pressure TDO

> No hydrogen

> No precious metal or other solid catalysts

> Cation may be regenerated in pulp mill based biorefinery

> Pyrolytic “deoxyhydrogenation” tolerant to impuritiesy y y y g p

> Future improvements likely from lignin (1 BOE potential) and improved carbohydrate yields


AcknowlegementsAcknowlegements> Co-Authors:

─ Paige A. Case

─ Scott J. Eaton

─ Adriaan R. P. van Heiningen

─ William J. DeSisto

> Significant Contributions─ Thomas J. Schwartz

─ Sedat H. Beis Mild hydro-t t t─ G. Peter van Walsum

─ Hemant P. Pendse

> Funding

treatment

─ UMaine Forest Bioproducts Research Institute

─ U.S. Dept. of Energy DE-FG02-07ER46373 and DE-FG36-08GO18165


Questions?Questions?

50°C 75°C 125°C 175°C150°C100°C85°C50°C122°F

75°C167°F

125°C257°F

175°C347°F

150°C302°F

100°C212°F

85°C185°F


Co-Processing of Standard Gas Oil

and Stable Pyrolysis Oil to

Hydrocarbon Fuels

Foster A. Agblevor

Utah State University

Foster A. Agblevor

- Biological Engineering, Utah State University, Logan UT.

- 1996-2010: Professor, Biological Systems Engineering, Virginia Polytechnic

Institute and State University, Blacksburg, VA.

- Research Interest: thermochemical and biochemical conversion of biomass

to fuels and chemicals.

Co-Processing of standard gas oil and

stable pyrolysis oils to hydrocarbon fuels

Foster A Agblevor, O. Mante*, R.

McClung**, F. Battaglia*, Ted Oyama*,

Biological Engineering, Utah State

University, Logan, UT

*Virginia Tech, Blacksburg, VA

**BASF Inc

tcbiomass11.presentation.Chicago.2011

Objectives

• Develop low temperature catalytic process

to produce stable pyrolysis oils

– Develop suitable catalysts for the process

– Develop integrated processing of biocrude

and petroleum crude oils to produce ―drop in

fuels‖

– Develop fundamentals of fractional catalytic

pyrolysis

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

OH

O

HO

H3CO

OH

OCH3

OCH3

O

O

O

OH

OCH3

OCH3

H3CO

OO

HO

H3CO

HO

OCH3

OCH3

OH

O

HO

H3CO

OH

OCH3

OCH3

O

O

OH

OCH3

OCH3

OCH3

O

O

O

OH

HO

O

O

O

O

OH

HO

OH

OH

O

O

O

OH

HO

OH

OH

O

O

O

OH

HO

OH

OH

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

O

O

O

OH

OH

OH

HO

HO

OHO

Lignin: 15-25%

Complex aromatic structure

Very high energy content

Cellulose: 38-50%

Polymer of glucose, very good biochemical feedstock

Biomass

Constituents

Hemicellulose: 23-32%

Polymer of 5 & 6 carbon sugar

Solid

Gas or Liquid

Pyrolysis molecular beam mass spectra of biomass

MCC

Poplar wood

13C-NMR spectra of FCP heavy oils

Materials and Methods

• Materials

– Hybrid poplar wood ground to pass 1-mm

screen

– Proprietary catalyst/silica sand

– Fluidizing gas –Nitrogen, pyrolysis gas

• 2-inch Bubbling fluidized bed reactor

• Pilot scale pyrolysis unit

Biomass Catalytic Pyrolysis Unit

1- Fluidized bed reactor,

3- Thermocouple, 4- Mass flow controller, 5- jacketed air-cooled

feeder tube, 6- Hopper, 7- Screw feeder, 8- Computer, 9- Heating tape,10-Hot gas filter, 11-Reservoir, 12-Condenser, 13-ESP,14-AC power supply, 15-Filter, 16-Wet gas meter, 17-Gas

chromatograph)

Materials and Method

• Method

• Pyrolysis temp = 450-600 C

• Vapor residence time = 1 s

• Electrostatic precipitator at 18-30 kV

• Run time – 2-3 hours

• Biomass feed rate 100 g/h.

• Catalyst = 100-150 g

Materials and Method

• Analysis

– FTIR and 13C NMR analysis of oils

– GC/MS analysis of liquid products

– High temperature simulated distillation

– GC analysis of gases

– FCC co-cracking

– 14C analysis of cracked products

Results and Discussion

Product yields for stable oils

Biomass FCP oil (wt%) Char (wt%) Gas (wt%) Oil pH

Hybrid poplar 33.3 12.2 55.0 3.4

Pinewood 43.3 35.1 21.5 3.3

Oakwood 41.8 33.8 24.6 4.4

Corn stover 40.1 24.8 35.5 4.2

Switchgrass 35.5 27.6 36.7 4.2

Hybrid poplar FCP oil

Molecular weight distribution of poplar FCP oil

Mn = 120 Mw = 257Mz = 555Mp = 134Mn/Mw = 2.136

Properties SPO

C (%) 71.16±1.81

H (%) 6.82±0.14

O (%) 21.85±1.95

N (%) <0.5

S (%) <0.05

Ash (%) <0.08

pH 3.73±0.03

Viscosity of fresh oil (cP) 11.24±0.20

Moisture content of fresh oil (%) 8.59±0.40

Viscosity of stored oil (cP) 12.70±0.20

Moisture content of stored oil (%) 8.66±0.20

Density fresh oil (g/ml) 1.116±0.001

Density stored oil (g/ml) 1.117±0.001

TAN (mgKOH/g oil) 41.01±0.82

HHV (MJ/kg) 30.5

Properties of stable pyrolysis oils (SPO).

13C-NMR SPECTRA OF CONVENTIONAL AND STABLE WOOD BIOOILS

0

200

400

600

800

1000

1200

1400

0 20 40 60 80 100

Tem

pera

ture

( d

eg

.F)

Wt.% distilled

Standard gasoil and biooils distillation curves—(BASF)

VPI-1

VPI-3

VPI-6

VPISU001

Pilot Scale

Std. Gas OIl

Catalyst ID VPI-1 VPI-3 VPI-6 HZSM-5 Pilot scale Disposition

<430oF (heavy naphtha(wt%))

17.5 21.5 17.5 21.5 21.5 Naphtha hydrotreater

430-650 oF[middle distillate --diesel and heating oils] (wt%)

42.5 57.5 45.5 46.5 45.0 Diesel or heating oil hydrotreater

>650oF [FCC unit feed] (wt%)

40 22.5 37 32 33.5 FCC feed hydrotreater

Distillate fractions of stable biomass pyrolysis oils (biosyncrude)

FCC Co-Cracking Data—(BASF)

Standard

4350VPI-4 VPI-4ST VPISU001

H2 (%) 0.61 0.53 0.44 0.56

Total C2- (%) 2.98 2.99 2.92 2.94

LPG (%) 16.00 16.19 16.00 15.95

Gasoline (%) 43.97 44.01 44.44 44.35

LCO (%) 17.06 16.93 17.23 17.23

HCO (%) 12.94 13.07 12.77 12.77

Coke (%) 7.06 6.81 6.64 6.76

Conversion (%) 70.00 70.00 70.00 70.00

Cat/Oil 6.00 6.08 5.96 5.81

200 150 100 50 0 PPM

13C-NMR SPECTRUM OF FCC CRACKED BIOOIL/GASOIL BLEND

Aromatic SPO

Co-cracked SPO

Aliphatic SPO

14C analysis of SPO/SIGO Blend cracked products

• Beta Analytical Inc, Miami, FL

• ASTM D6866 method used for the analysis

• The cracked SPO/SIGO product contained 3% biocarbon.

Parameter As received

basis

Calorific value 24.94 MJ/kg

Karl Fischer water content (%) 2.89

Ash (%) <0.09

Carbon (%) 65.96

Hydrogen (%) 7.11

Oxygen (%) 26.36

Nitrogen (%) 0.54

Sulfur (%) <0.5

Chlorine (ppm) 54

Viscosity (cP) 1024

pH 2.8

Characteristics of FCP Heavy oil.

Summary

• We have developed a process to produce stable FCC-crackable pyrolysis oils.

• The viscosity of the stable pyrolysis oil increased from 10.1 cSt to 11.4 cSt after ten months of storage at ambient laboratory conditions

• The stable pyrolysis oils were completely distillable without char formation (no residuum)

• 85/15 blend of Standard Gulf coast FCC feed and stable pyrolysis oils were crackable without any problem. The blend produced slightly less coke than the Standard Gulf coast FCC feed cracked under similar conditions

Summary

• How transformational is the technology?

• Pyrolysis oils could be co-processed in

existing petroleum refineries

• Existing petroleum refineries could

claim ―green credits‖ by processing the

biosyncrude.

• We have also developed technology to

produce heavy oils to complement

stable oils

Grassoline for your car?

Acknowledgement

• DOE for funding the pyrolysis oil stability

studies.

• Contract# DE-FG36-08GO18214-1

Thank you!!

• Questions?

The Role of the Lignocellulosic

Composition on the Pyrolysis of

Waste Crops: Fractionation and

Kinetic Study

Marion Carrier

Stellenbosch University

Marion Carrier obtained a degree in chemical engineering from the CPE

Lyon Engineering School as well as a Masters degree in Analytical

Chemistry from the University of Lyon.

In 2007, she completed her PhD in Chemistry at the University of Lyon in

collaboration with IRCELYON-CNRS (Lyon), INRA (Thonon-les-bains) and

Cemagref (Lyon) laboratories. The focus of her PhD was the treatment of

wastewaters from wine fermentation by advanced oxidation processes:

photocatalysis, sonolysis and catalyzed wet air oxidation.

Marion joined the Department of Process Engineering in November 2008 as a

postdoctoral research fellow and she has been granted by the NRF

Innovation fellowship in 2010 to pursue her research on the conversion of

lignocellulosic biomass to biofuels and chemicals with pyrolysis and

gasification.

The role of the

lignocellulosic composition

on the pyrolysis of waste

crops: Fractionation and

kinetic study

Dr Marion Carrier, Stellenbosch University, South-Africa

Footer goes here2

tcbiomass2011

Lignocellulosic composition

Lignin

Really complex

3 main

compounds

Hemicelluloses 20-40 %

Polymerisation degree 50-300

Hexosanes/Pentosanes blocks

Cellulose 43-60 %

Polymerisation degree 10000

Glucose blocks linked by ether bonds Mineral content

Si, K, Mg, Ca, Na, P, Fe, Al, Zn

Linked with cellulose

Footer goes here3

tcbiomass2011

How to predict the influence of biomass

nature on the pyrolysis process?

> Natural or synthetic compounds?

> Which wet chemical extraction methods?

> Which type of kinetic study?

Footer goes here4

tcbiomass2011

OBJECTIVE

Understand the thermal behaviour of the lignocellulosic

composition to reach efficient pyrolysis conversion

> by understanding the role of interactions between

macrocomponents,

> by establishing a mathematical correlation between the

lignocellulosic composition and thermal properties.

Footer goes here5

tcbiomass2011

> Using synthetic biomass studies, no detectable

interaction among the commercial components during

pyrolysis.

> A possible synergistic effect arising from the coincidence

of the ingredients in the parent sample in the favor of

lowering the activation energy.

Natural or synthetic compounds?

Raveendran et al., Fuel (1996) 75 (8) 987-998

Haykiri-Acma et al., Fuel Processing technology (2010) 91 759-764.

Footer goes here6

tcbiomass2011

Which wet chemical analysis to

fractionate the whole structure?

NDF: Neutral Detergent Fibre

ADF: Acid Detergent Fibre

ADL: Acid Detergent Lignin

Weende

HOLO: Holocellulose

α: α-cellulose

LIG: Klason lignin

Sluiter et al., J.Ag. Food Chem. (2010) 58 (16) 9043-9053.

Footer goes here7

tcbiomass2011

Results

Method Lignin(wt% dry)

Holocellulose(wt% dry)

Calculated

hemicelluloses(wt% dry)

-cellulose(wt% dry)

Extractibles(wt% dry)

“wood-

industry”35 ± 2 (a) 68 ± 5 (d) 34 ± 9 (e) 34 ± 4 (f) 3 ± 2

“food-

industry” 22 ± 5 (c) 4 ± 2 (g) 26 ± 10 (h)

“food-

industry” 18 ± 3 (b) 13 ± 2 (k)

37 ± 6 (j)

35 ± 9 (l)

“wood-

industry”25 ± 2 (a) 71 ± 5 (d) 28 ± 10 (e) 43 ± 5 (f) 5 ± 3

“food-

industry” 16 ± 4 (c) 9 ± 4 (g) 41 ± 16 (h)

Extraction methods used: (a) LIG, (b) ADL, (c) ADLB, (d) (HOLO), (e) (HOLO-α), (f)

(α), (g) (NDFB-ADFB), (h) (ADFB-ADLB), (i) unknown, (j) Weende, (k) NDF-ADF

and (l) NDF-ADL.

Yields of lignin, holocellulose, hemicelluloses and cellulose from fern (dry matter, 91 %) and

wood (dry matter, 97 %).

Footer goes here8

tcbiomass2011

Results

-1

0

1

2

3

4

5

6

0 200 400 600 800

DT

G d

m/d

m0

(%)

Temperature (°C)

α-Cellulose

Lignin

Holocellulose

Crude poplar

Washed

DTG curves of the crude and washed biomasses, and macromolecules (5 ºC min-1): holocellulose, α-cellulose, and lignin extracted from the washed Populus nigra L.

Footer goes here9

tcbiomass2011

Results

Hemicellulosesy = 49x

R2 = 0.99

y = 32xR2 = 0.90

0

100

200

300

400

0 5 10

Aera

(au)

Mass (mg)

α-cellulose

Cellulose

pulps-Pine

α-cellulose

(wt.% dry) (1)

wood

(wt.% dry) (2)

fern

(wt.% dry) (2)

110106 87.6 79 ± 7 74 ± 6

5092 90.3 97 ± 7 91 ± 6

5094 92.8 96 ± 8 91 ± 7

5096 93.6 99 ± 8 93 ± 7

Cellulose

pulps-Pine

Hemicelluloses

(wt.% dry) (3)

wood

(wt.% dry) (2)

fern

(wt.% dry) (2)

110106 11.7 8 ± 4 17 ± 10

5092 7 6 ± 3 13 ± 7

5094 4.7 6 ± 4 13 ± 9

5096 3.6 5 ± 4 10 ± 9

Carrier et al., Biomass and Bioenergy, 35 (2011) 298-307.

(1) R10 method

(2) Calibration curves

(3) 100-R18 method

Calibration curves for the wood.

Footer goes here10

tcbiomass2011

Which kinetic method to apply for

solid state reactions?

„Model-free‟ or isoconversional methods

Model-fitting

Differential method or Integral method

Arrhenius rate expressionk(T): reaction rate constant

T: Temperature in K

A: Frequency factor or pre-

exponential

Ea: Activation energy

R: Universal gas constant

Kinetic expressionα: degree of conversiont: timek(T): reaction rate constant

f(α): conversion function

White et al., Journal of Analytical and Applied Pyrolysis, 91 (2011) 1-33

Vyazovkin et al., Thermochimica Acta, 520 (2011) 1-19.

Kinetic triplet: A, Ea and f(α)

Friedman‟s method

Footer goes here11

tcbiomass2011

Results

Experimental results

Sugar cane bagasse

0

10

20

30

40

50

0

50

100

150

200

250

0 0.5 1

Conversion α

ln(A

*f(α

)) (

1/s

)

E (

kJ

/mo

l)

010203040506070

0

100

200

300

0 0.5 1

Conversion α

ln(A

*f(α

)) (

1/s

)

E (

kJ

/mo

l)

Hemicelluloses

0

10

20

30

40

50

60

0

100

200

300

0 0.5 1

Conversion α

ln(A

*f(α

)) (

1/s

)

E (

kJ

/mo

l)

Cellulose

0

10

20

30

40

50

60

0

100

200

0 0.5 1

Conversion α

ln(A

*f(α

)) (

1/s

)

E (

kJ

/mo

l) Lignin

Footer goes here12

tcbiomass2011

Results

Comparison of predicted and experimental curves of bagasse pyrolysis at 50°C min-1

Aboyade et al., Thermochimica Acta 517 (2011) 81-89.

0

0.005

0.01

0.015

100 200 300 400 500 600

DT

G (

s-1

)

Temperature (oC)

Cellulose

predictedHemicelluloses

predicted

Lignin predicted

Total predicted

Experimental

Footer goes here13

tcbiomass2011

Conclusions

> Variation inherent to the selection of the extraction method (∆% = 20 %).

> Alkaline extraction recommended for the hemicellulose

content determination.

> α-cellulose and hemicellulose contents determination

successful.

> Kinetic parameters determined by Friedman‟s method

applicable to the prediction of experimental data.

> TGA technique is suitable to point out and quantify

synergistic effects.

Footer goes here14

tcbiomass2011

Future works

> Improve the lignin extraction technique.

> Determinate the calibration curve for the lignin.

> Compare the kinetic parameters of extracted products

with the ones obtained from predicted products.

> Evaluate the accuracy and precision of predictions.

Footer goes here15

tcbiomass2011

Acknowledgements

> Supercritical team from CNRS-ICMCB, Bordeaux, France

(Cyril Aymonier, Anne Serani-Loppinet, Michel Mench).

> Process Engineering department from Stellenbosch

University, South Africa (Hansie Knoetze, Johann

Görgens, Wale Aboyade).

> The National Research Foundation for sponsoring the

study.

THANK YOU

Lignin Pyrolysis in a Fluidized Bed

Reactor with Fractional

Condensation

Cedric Briens

ICFAR at the University of Western Ontario

Lignin Pyrolysis in a Fluidized Bed Reactor

Pietro Palmisano, Federico Berruti,

Valentina Lago, Franco Berruti,

Cedric Briens

Why pyrolyze lignin?

• Organosolv lignin:– Newer process

• Kraft lignin:– Kraft process used for most of worldwide paper

production– Black Liquor side product is currently burned– Lignin can be extracted from Black Liquor

• 50 million tonnes of lignin available worldwide• Most of it is burned

Why pyrolyze lignin?

Cracking of lignin → interesting aromatic products?

Objective

• Pyrolyze lignin (> 200 g / run)

• Lignin cannot be pyrolyzed in standard equipment

• Develop equipment for reliable pyrolysis of lignin

Outline

• Equipment

• Why is lignin difficult to pyrolyze?

• Solutions

• Results

• Conclusions

• What is next

Equipment

Solid feeder

FluidizedBedReactor

Condensing zone

Gas sampling

N2 for fluidization

Reactor diameter = 7.5 cm (3 in)

1.5 kg of sand with dpsm = 180 μm

Lignin

• Very fine particles ( < 30 μm)

• Particle density = 575 kg/m3

Why is lignin difficult to pyrolyze?

• Lignin starts melting at low temperature: 150 – 200 ºC

• Lignin needs a high reactor temperature to crack fully

1) Solids feeder plugs

Lignin

Fluidized sand

Why is lignin difficult to pyrolyze?

• Lignin starts melting at low temperature: 150 – 200 ºC

• Lignin needs a high reactor temperature to crack fully

1) Solids feeder plugs

2) Low density foam forms

at the bed surfaceLignin foam

Lignin

Fluidized sand

3 in

Solution 1: Pulsed feeder

N2 Pulse

N2 continuous

Solution 1: Pulsed feeder

Foam forms at bed surface (only with Kraft Lignin)

Bio-oil vapours and gases

What causes foam at the top?

2 possibilities:

1) Injected particles do not mix well with sand particles

2) Reacting lignin particles rise to the bed surface

Solution 2: Premix lignin with sand

Sand premixed with lignin before injection into the hot bed (sand/lignin = 5/1 wt/wt).

3 in

Solution 3: Use a mechanical stirrer

Mechanical stirrer in the fluidized bed to bringsolids from the bed surface down into the bed

Solution 3: Use a mechanical stirrer

No mixer. 200g of lignin fed.

Mixer. 80 rpm.200g of lignin fed.

Lignin particles rose to the surface and agglomerated

Strong top to bottom mixing: no foam

Reactor temperature, oC

440 460 480 500 520 540 560

yie

ld,

wt%

0

10

20

30

40

50

60

70

80

char

bio-oil

gas

Product yields: Kraft lignin1.8 s vapor residence time


440 460 480 500 520 540 560 580 600 620

yie

ld,

wt%

0

10

20

30

40

50

60

char

bio-oil

gas

Product yields: Kraft lignin0.4 s vapor residence time


440 460 480 500 520 540 560

yie

ld,

wt%

20

25

30

35

40

45

50

0.4 s

1.8 s

Effect of vapor residence time on liquid yield


400 450 500 550 600 650

HH

V, kJ/g

8

10

12

14

16

18

20

22

0.4 s

1.8 s

Heating value of bio-oil


400 450 500 550 600 650

(liq

uid

HH

V)

/ (lig

nin

HH

V),

%

5

10

15

20

25

30

35

40

0.4 s

1.8 s

% energy recovered in bio-oil

Bio-oils from Organosolv and Kraft lignins

Bio-oil from Kraft lignin

Bio-oil from Organosolv lignin

Yield at 550 ºC, 1.8 s 31% 35%

Pesticide activity X 3

Conclusions

• First practical technology for fast Kraft lignin pyrolysis

• Low but reasonable liquid yields

• Energy from lignin recovered in liquid < 40%

• Strong effect of vapor residence time

What is next

• Detailed chemical analysis of bio-oil

• Separation methods to extract valuable compounds

• Study of effect of vapor residence time

• Replace mechanical stirrer with draft/lift tube

Acknowledgements

• Technical support:– Clayton Stanlick and Rob Taylor (mechanical stirrer)

– Mohammad Hossain and Dr. Ian Scott, Agriculture and AgriFood Canada (Pesticide testing)

• Lignoworks network for financial support:– NSERC

– FPInnovations

– Lignol

– Weyerhaueser

Prospects for a Thermolytic

Sugar Platform

Robert Brown

Bioeconomy Institute at Iowa State University

Dr. Robert Brown is Anson Marston Distinguished Professor of

Engineering and Gary and Donna Hoover Chair in Mechanical Engineering at

Iowa State University (ISU).

He also holds courtesy academic appointments in the Departments of

Chemical and Biological Engineering and Agriculture and Biosystems

Engineering. He is the director of ISU’s Bioeconomy Institute.

His research focuses on the thermochemical processing of biomass and

fossil fuels into energy, fuels, and chemicals.

Prospects for a ThermolyticProspects for a Thermolytic Sugar Platform

Robert C. Brown

g

Center for Sustainable Environmental TechnologiesIowa State University

Ames IAAmes, IA

TC Biomass ConferenceChicago, IL

September 27‐30, 2011

AcknowledgmentsIowa State University’s thermochemical research program is conducted atIowa State University s thermochemical research program is conducted at the Center for Sustainable Environmental Technologies (CSET). Current staff include Ryan Smith, Marge Rover, Pat Johnston, Lysle Whitmer, and Jordan Funkhouser and postdoctoral research associates Sunitha Sadula and Tristan Brown. Faculty collaborators include Profs. Brent Shanks, Guiping Hu, and Xianglan Bai at ISU and Profs. Wolter Prins and Frederik Ronsse at Ghent University, Belgium. I am indebted to several current and former graduate students who have contributed to this presentation:former graduate students who have contributed to this presentation: Pushkaraj Patwardhan, Mark Wright, Yanan Zhang, Najeeb Kuzhiyil, AJ Pollard, Dustin Dalluge, Andrew Olthoff, and Andrew Friend.

CSET’ h h i l j d b h C PhilliCSET’s thermochemical projects are supported by the ConocoPhillips Company, ADM, the U.S. Department of Energy, the National Advanced Biofuels Consortium, the U.S. Department of Agriculture, the state of Iowa, and gifts from Gary and Donna Hoover and John Pappajohn.Iowa, and gifts from Gary and Donna Hoover and John Pappajohn.

The goal of this work is to develop a thermal process for the production of “cheap sugars” from cellulosic biomasscheap sugars from cellulosic biomass

Fast PyrolysisRapid thermal decomposition of organic compounds in the absence of oxygen to produce

Conventional Products from Fast Pyrolysisyg p

predominately liquid product

Composition of Conventional Bio‐Oil from Oak Wood (wt%)

y y

Aqueous phase (carbohydrate‐derived)

Oil from Oak Wood (wt%)

Saccharides 14.1

Aldehydes 16.3

Pyrolytic lignin (water insolubles)

Char*

Syngas

Biochar

Furans 1.4

Ketones 3.2

Carboxylic acids 4.7

Syngas

*Also called biochar

Phenolic Monomers 7.3

Other GC/MS Detected 2.2

Phenolic oligomers 22.4

Water 28.4

Source: ISU (2010)

Cellulose Decomposition: Conventional WisdomConventional Wisdom

Fast pyrolysis yields predominately anhydrosugar, which decomposes into low molecular weight products or in

Li ht t

decomposes into low molecular weight products or, in the presence of char, dehydrates to char and water.

Fast

Decomposition

Levoglucosan

Light oxygenates

Tarry vaporsVaporization

Cellulose

SlowChar + water

Char + waterChar-catalyzed

dehydration

Vaporization

Ch ll i C i l Wi d bChallenging Conventional Wisdom about Carbohydrate Pyrolysis (Working Hypotheses)

• Pure holocellulose depolymerizes to monomeric anhydrosugars;

• Alkali and alkali earth metals (AAEM) catalyze decomposition of holocellulose to undesirable “light oxygenates” inundesirable light oxygenates in competition with depolymerization;

• AAEM can be “passivated” through biomass Pyrolytic Molasses

pretreatments;

• Sugar yields are strongly influenced by secondary processes of evaporation andsecondary processes of evaporation and polymerization of anhydrosugars

/Fundamental Studies with Py‐GC/MS or FIDFrontier ~ 500 μg

FeedstockMicro-pyrolyzer

500 μg

He

Capillary Separation

Mass Spectrometer

( )Capillary Separation Column (MS)

Gas Chromatograph (GC)

Effects of Cations on Deconstruction of Cellulose

20Formic acid

60 LevoglucosanNaCl

NaClKCl

10

20

Wt %

20

40

wt %

NaClKClMgCl2CaCl2

MgCl2CaCl2

00 0.1 0.2 0.3 0.4

moles of salt/g of cellulose

00 0.1 0.2 0.3 0.4


3

4

%

Acetolmoles of salt/g of cellulose

3

4

5

%

Furfural

NaClNaClKCl

0

1

2

Wt %

0

1

2Wt

KClMgCl2CaCl2

MgCl2CaCl2

Patwardhan et al., Bioresources Technology (2010) 4646-4655.

00 0.1 0.2 0.3 0.4


00 0.1 0.2 0.3 0.4


M h i f C ll l D iti Vi C tiMechanism of Cellulose Decomposition Via CationsCoordination bonding of cations on cellulose

induces homolytic fission of glucose rings

Cellulose

Ca2+

y g gK+

Depolymerized fragment

Intermediate

LevoglucosanPonder et. al., J Anal. App.Pyrolysis, 1991, Yang et al. Chem. Res. Chinese U. 2006

Passivating Alkali in BiomassPassivating Alkali in Biomass

Pretreating switchgrass with most mineral acids (with the exception of nitric acid)

TC Biomass POSTER: Kuzhiyil et al. “Passivating Alkali Metal during Pyrolysis of Biomass”

Pretreating switchgrass with most mineral acids (with the exception of nitric acid) significantly increases yields of anhydrosugars and decreases yields of light oxygenates. Organic acids and nitric acid had little affect on pyrolysis.

Comparison of Different Pretreatments

16.0018.0020.00

basi

s)

pSwitchgrass ControlAcetic AcidFormic AcidNitric Acid

10.0012.0014.00

mas

s (w

et Hydrochloric Acid

Phosphoric AcidSulfuric Acid

4.006.008.00

t% o

f bio

m

0.002.00

Light Oxygenates Anhydrosugars Furans Phenols

wt

Th i i l l l f id i f iThere is an optimal level of acid infusionTC Biomass POSTER: Kuzhiyil et al. “Passivating Alkali Metal

during Pyrolysis of Biomass”during Pyrolysis of Biomass

The AAEM passivation hypothesis predictsThe AAEM passivation hypothesis predicts optimal acid infusions

TC Bi POSTER K hi il t l “P i ti Alk li M t lTC Biomass POSTER: Kuzhiyil et al. “Passivating Alkali Metal during Pyrolysis of Biomass”

Correlation between amount of minerals in biomass and amount of acid required to achieve optimal levoglucosan yieldof acid required to achieve optimal levoglucosan yield

Role of Secondary Reactions in Determining Yield of Levoglucosan

• Rapid quenching of primary products thought essential to prevent decomposition ofessential to prevent decomposition of levoglucosan

Ch th ht t t l d h d ti f• Char thought to catalyze dehydration of levoglucosan

Decomposition of levoglucosan suppressed by acid washing of char, which suggests that alkali is the catalytic agent

TC Biomass POSTER: Ronsse et al. “Secondary reactions of levoglucosan and char in the fast pyrolysis of cellulose”

unwashed

acid washed

M T f M Li it S Yi ld f AAEMMass Transfer May Limit Sugar Yields from AAEM Passivated Biomass

TC Biomass POSTER: Bai et al. “The Role of Levoglucosan

0.010

0.012

5 Deg. C/minLG evaporation peak

/s)

Dehydration peak

gPhysiochemistry on Cellulose Pyrolysis”

Cellulose

0.004

0.006

0.008

2 mg open cup

10ss Loss Ra

te (m

g/

y p

Differential Thermogravimetry

L l

Pyrolysis

0.000

0.002

50 100 150 200 250 300 350 400 450 500

10 mg open cup

Mas Levoglucosan

Temperature (⁰C) Vaporization Polymerization

DehydrationResidue of cellulose y

CharTar

pyrolysis in TGA sample cups

ll l d dCellulose Decomposition: Updated

Fast pyrolysis consists of two stages of competitive

• Depolymerization and alkali‐catalyzed decomposition of cellulose

Fast pyrolysis consists of two stages of competitive processes:

• Vaporization and polymerization/dehydration of levoglucosan

Alk li t l d d iti

Fast

Alkali-catalyzed decompositionLight oxygenates

LG polymerization/ dehydration

Depolymerization Furans + char + waterCellulose

SlowChar + water

LG vapors

Depolymerizationto levoglucosan

LG evaporation

Rethinking Strategy for Upgrading Recover Bio Oil asRethinking Strategy for Upgrading: Recover Bio‐Oil as Stage Fractions

TC Biomass POSTER: Pollard et al. “Analysis of Bio-oil Produced in a C o ass OS o a d et a a ys s o o o oduced aFractionating Bio-Oil Recovery System during Pyrolysis of Red Oak,

Switchgrass, and Cornstover”

Biomass feederSF 1

SF 2: ESPs SF 4: ESP

Pyrolyzer

SF 1: Condenser

SF 3: C d

CyclonesCondenser

SF 5:Condenser

R thi ki St t f Bi Oil U diRethinking Strategy for Bio-Oil UpgradingTC Biomass POSTER: Pollard et al. “Analysis of Bio-oil Produced in a

Fractionating Bio-Oil Recovery System during Pyrolysis of Red Oak, Switchgrass, d C t ”

Current pilot plant at ISU’s BioCentury Research Farm produces five distinct t f ti f bi il

and Cornstover”

stage fractions of bio-oil

Bio-Oil from Red Oak Stage Fraction 1

Stage Fraction 2

Stage Fraction 3

Stage Fraction 4

Stage Fraction 5

Yield (wt% of biomass)) 21.0 26.5 5.5 11.1 36.0Moisture (wt% bio-oil) 7 8 9 15 63Water Insoluble (wt% bio-oil) 44 45 8 13 <1Levoglucosan (wt% bio-oil) 4.8 3.2 1.0 1.5 0.2Levoglucosan (wt% bio oil) 4.8 3.2 1.0 1.5 0.2Total Acid Number 35 32 79 117 117Oxygen content (wt% m.f. basis) 28.6 29.1 41.1 39.6 53.3Higher Heating Value (MJ/kg) 24.2 24.4 20.2 18.7 7

Heavy ends (sugar and phenol oligomer-rich fractions of bio-oil)

Viscosity (cSt @ 40°C)* 4400 3400 36 50 1.3

Separating Heavy Ends into SugarSeparating Heavy Ends into Sugar and Phenolic Oligomers

TC Biomass POSTER: Rover et al “Sugar Recovery from the

Sugar solution (20-40 wt%)

TC Biomass POSTER: Rover et al. Sugar Recovery from the Heavy Ends of Fractionated Bio-Oil”

Raffinate (mostly phenolic oligomers)

Estimating the Cost of Pyrolytic SugarsEstimating the Cost of Pyrolytic SugarsTC Biomass POSTER: Zhang et al. “Biomass Fast

Pyrolysis and Upgrading for Production of Cheap Sugars

Product Yield Market ValueHydrogen 8.23 million kg/yr $2/kgGasoline 8.60 million gal/yr $3.26/galDiesel 7.25 million gal/yr $3.26/galProduct Yield Production CostSugar 128 millionSugar

(glucose syrup) 128 million

kg/yr$0.54/kg

Conclusions• AAEM passivation increases levoglucosan fromAAEM passivation increases levoglucosan from biomass pyrolysis to levels comparable to pyrolysis of pure carbohydrate;

• Levoglucosan undergoes competing processes of evaporation (recovered as “tar”) and polymerization (dehydrates to char and furans);(dehydrates to char and furans);

• Strategy of recovering bio‐oil as stage fractions allows separation of sugars;p g

• Cost analysis of products from non‐optimized process are promising.

Other presentations from CSET students and staff

• PLENARY/– Dalluge et al., “Pyrolytic Pathways to Increasing the Lignin‐Derived Monomer/Oligomer Ratio in

Bio‐oil.”

• POSTERS– Broer et al “Biomass Gasification and Syngas Clean‐up;”Broer et al., Biomass Gasification and Syngas Clean up;

– Brown et al., “Technoeconomic Analysis of Biobased Chemicals Production via Integrated Catalytic Processing;”

– Creager et al., “High Pressure, Oxygen Blown Entrained‐Flow Gasification of Bio‐oil;”

– Del Campo et al., “Characterization of Fast Pyrolysis Biochars for Safe Application;”

– Friend et al., “Co‐firing Pellets of Coal and Pyrolysis‐derived Binder;”

– Rover et al., “Analysis of Sugars and Phenolic Compounds in Bio‐oil;”

Sadula et al “Stability of Bio Oil as Measured by Gel Permeation Chromatography;”– Sadula et al., Stability of Bio‐Oil as Measured by Gel Permeation Chromatography;

– Wang et al., “Pyrolysis of Lipid‐rich Biomass for Fuel and Chemicals Production;”

– Whitmer et al., “Gas Cleaning Systems for Syngas and Bio‐oil Production;”

– Woolcock et al., “Analysis of Tar Compounds at Trace Levels in Cleaned Syngas;”, y p y g ;

– Zhang et al., “Techno‐Economic Analysis of Co‐Production of Hydrogen and Transportation Fuels from Corn Stover.”

Pyrolytic Pathways to Increasing the

Lignin-Derived Monomer / Oligomer

Ratio in Bio-oil

Dustin Dalluge

Iowa State University

Dustin Dalluge is a Graduate Research Assistant working toward his

Ph.D. in Mechanical Engineering and Biorenewable Resources & Technology

at Iowa State University under the supervision of Dr. Robert Brown.

Dustin received his A.S. in Engineering at North Iowa Area Community

College and B.S. in Mechanical Engineering from Iowa State University.

His research areas are in fast pyrolysis, feedstock pretreatments, bio-oil

fractionation, and pyrolysis fundamentals.

Pyrolytic Pathways to

Increasing the Lignin-

Derived Monomer/Oligomer

Ratio in Bio-oil

Dustin Dalluge, Department of Mechanical Engineering, Iowa State University

Dr. Robert C. Brown, Center for Sustainable Environmental Technologies, Iowa State University

Footer goes here2

tcbiomass2011

Project Goals

• Understand the formation of the lignin-derived, water

insoluble compounds in bio-oil

• Develop methods to produce bio-oil with a higher ratio of

monomers to oligomers

> Leads to bio-oil with improved properties for

upgrading to transportation fuels and chemicals

Footer goes here3

tcbiomass2011

Advantages of Phenolic Monomers

• Higher C/O ratio = higher energy density than carbohydrate monomers

• Many phenolic monomers are liquids and soluble in solvents

> Easier to upgrade than oligomers

> Less sticky and complex than oligomers

• Phenolic monomers could be upgraded separately from sugars

Footer goes here4

tcbiomass2011

Defining The Resource Base

23-53% Cellulose12-32% Lignin

12-25% Hemicellulose

Biomass

0.5-16% Ash

(Wyman, 1996.)

Footer goes here5

tcbiomass2011

Lignin Facts

• Enzyme-mediated polymerization of three precursors:

> p-Coumaryl alcohol (H-lignin)

> Coniferyl alcohol (G-lignin)

> Sinapyl alcohol (S-lignin)

Most common linkages:

β-O-4 (60%+) > α-O-4 > β-5 > β-1 > others

H O

O

OH

OH

O

O

C OH

OCH3

O

HO

O

O

HO

HO

OH

O O

OH

OH

OHHO

HOO

OCH3

HO

O OH

OH

OOHC

OCH3

HO

OH

OC

OH

O

OCH

HO

HO

O

OCH3HO

HO

OH

O

OCH3

O

OO

H

HOO

OCH3

3

3CH O

3CH O

3CH O

3CH O3CH O

3CH O

3CH O

3CH O

3CH O

3CH O

(Amen-Chen, 2001)

Footer goes here6

tcbiomass2011

High

Molecular

Lignin, 25%

Reaction

Water, 10%

Moisture,

10%GC-

detectable,

10%

Quantified via

GC, 30%

HPLC

detectable,

15%

Typical Bio-oil Composition

(Mohan, 2006)

Contains around 25% high molecular weight lignin-derived compounds

Also called “pyrolytic lignin” or “water insolubles”

Footer goes here7

tcbiomass2011

Formation of Lignin-Derived Oligomers

H O

O

OH

OH

O

O

C OH

OCH3

O

HO

O

O

HO

HO

OH

O O

OH

OH

OHHO

HOO

OCH3

HO

O OH

OH

OOHC

OCH3

HO

OH

OC

OH

O

OCH

HO

HO

O

OCH3HO

HO

OH

O

OCH3

O

OO

H

HOO

OCH3

3

3CH O

3CH O

3CH O

3CH O3CH O

3CH O

3CH O

3CH O

3CH O

3CH O

Approximate size of

lignin-derived oligomer

in bio-oil

Hypothesis 1:

Pyrolysis does not sufficiently

depolymerize lignin

Hypothesis 2:

Monomers formed during

pyrolysis repolymerize in

secondary reactions or after

condensation of vapors

(Piskorz, 1999)

Footer goes here8

tcbiomass2011

Vinyl Phenols in Bio-oil

• Vinyl phenols appear as the most dominant products in

primary lignin pyrolysis (GC-MS analysis of vapors)

• Very few vinyl phenols are found in the analysis of bio-oil

(condensed vapors and aerosols)

4-vinylphenol 2-methoxy-4-

vinylphenol

2,6-dimethoxy-4-

vinylphenol

(Patwardhan, 2011)

Footer goes here9

tcbiomass2011

Polymerization of Vinyl Phenols

• Vinyl phenols formed during lignin pyrolysis will be very

reactive

• Gas-phase polymerization of vinyl phenols with other

phenol monomers will produce phenolic oligomers

• Phenolic oligomers have little vapor pressure and will

condense to aerosols in the gas flow

Footer goes here10

tcbiomass2011

Disappearance of Vinyl Phenols

Theoretical Yield1

(wt% of lignin)

Actual Recovery inCorn Stover Bio-oil2

(wt% of lignin)

Total Monomeric

Phenols20.0% 10.2%

Vinyl Phenols 7.3% 0.0%

1 – Primary products of corn stover lignin micropyrolysis (Patwardhan, 2011)

2 – Recovery of whole bio-oil from a fluidized bed reactor (Pollard, 2009)

– Assuming lignin content of 18.7% in corn stover (U.S. DOE)

Note: Corn stover bio-oil also contained 12.5% water insolubles based on biomass

weight (24.8 wt.% of bio-oil) – consisting largely of phenolic oligomers

Footer goes here11

tcbiomass2011

Phenolic Monomer Recombination

0

5

10

15

20

25

30

35

0 1000 2000

Are

a %

Mol. Wt. (Da)(Relative to Polystyrene standards)

CCS Mix

CCS Mix Py

CCSA Mix Py

• Gel Permeation Chromatography (GPC) analysis on mixtures of lignin precursors

─ Coniferyl alcohol, coumaryl alcohol and sinapyl alcohol (CCS Mix)

─ Condensed products from pyrolysis of at 500oC of CCS Mix (CCS Mix Py)

─ Condensed products from pyrolysis at 500oC of CCS Mix and acetic acid. (CCSA Mix Py)

• Pyrolysis of precursors promotes polymerization

• Polymerization greatly enhanced by acetic acid

(Patwardhan, 2011)

Footer goes here12

tcbiomass2011

Attempts to Neutralize Acid

Catalysts

• Hypothesis: Rapid conversion of acetic acid to acetate will

prevent it from reacting with phenols released during

pyrolysis

• Test: Pyrolyze lignin in an arrangement that forces

pyrolysis vapors through a shallow bed of basic salt

(NaHCO3 or KHCO3); Analyze vapors via GC-MS

Footer goes here13

tcbiomass2011

Experimental Setup

Lignin

Quartz Wool

Quartz Wool

Suspended

Salt Bed

Salt Bed

Lignin

Quartz Wool

Control

Vapors

Footer goes here14

tcbiomass2011

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000A

rea

(uV

*m

in)

Control

NaHCO3 Suspended Bed

KHCO3 Suspended Bed

Changes in Phenol Composition by Passing Lignin

Pyrolysis Vapors Through Bed of Basic Salt

• Complete neutralization of

acetic acid

• Increased phenolic monomers

• Vinyl phenols reduced

Footer goes here15

tcbiomass2011

What is the Effect of Directly Mixing

Alkali and Alkaline Earth (AAEM) Salts

with Lignin Prior to Pyrolysis?

• Previous research at ISU has shown that cations strongly

increase ring fragmentation during cellulose pyrolysis

• Experiments were conducted with several AAEM cations:

Potassium, sodium, calcium, and magnesium

• Experiment – To look at effect of only the cations, the

anion was kept constant as acetate, which forms a

thermally unstable salt, susceptible to decomposition

during pyrolysis

Footer goes here16

tcbiomass2011

Experimental Setup

Lignin +

1wt% Salt

Quartz Wool

Lignin/Salt

Mixture

Lignin

Quartz Wool

Control

Vapors

Footer goes here17

tcbiomass2011

0

5000

10000

15000

20000

25000

Are

a (µ

V*

min

)

Lignin

Magnesium Acetate

Calcium Acetate

Potassium Acetate

Sodium Acetate

Effect of Cations on Lignin Pyrolysis

Presence of ~1.0wt% K or Na

almost doubled the yield of

phenol, 2-methoxyphenol, and

2,6-dimethoxyphenol

Footer goes here18

tcbiomass2011

What is the Effect of Thermally

Stable Salts on Lignin Pyrolysis?

• Previous research at ISU has discovered that thermally

stable AAEM salts are less prone to cause ring

fragmentation during cellulose pyrolysis

• Do thermally stable salts also affect lignin

depolymerization?

• Experiment: Infuse 1.0 wt% potassium in the form of

several salts into corn stover lignin – pyrolyze

Footer goes here19

tcbiomass2011

0

5000

10000

15000

20000

25000

Are

a (µ

V*

min

) Control

Sulfate

Chloride

Acetate

Lignin does not as readily depolymerize

in the presence of thermally stable salts

Potassium sulfate has no

significant effect on lignin

pyrolysis

Footer goes here20

tcbiomass2011

Two Approaches

1. Alkali, especially potassium, has shown to effect the

pyrolysis products of lignin when infused into the solid

2. Adding a bed of alkali salt above the lignin is shown to

dramatically shift the products toward recoverable

monomeric phenols

> Experiment: Test the effect of alkali on solid lignin as well as the

pyrolysis vapors – test the effect of the two simultaneously

Footer goes here21

tcbiomass2011

Experimental Setup

Lignin +

1wt% Salt

Quartz Wool

Lignin/1%K

(Kacetate) Mixture

Lignin

Quartz Wool

Quartz Wool

KAcetate

Suspended

Bed

Salt Bed

Lignin

Quartz Wool

Control

Lignin +

1wt% Salt

Lignin/1%K

(Kacetate) +

Kacetate

Suspended Bed

Quartz Wool

Quartz Wool

Salt Bed

Footer goes here22

tcbiomass2011

0

5000

10000

15000

20000

25000A

rea

(uV

*m

in)

Control

Lignin/1%K (Kacetate) Mixture

KAcetate Suspended Bed

Lignin/1%K (Kacetate) + KAcetate Suspended Bed

Cumulative Effects of Alkali

• Decreased yield of reactive vinyl phenols

• Increased yield of recoverable

monomeric phenols

Footer goes here23

tcbiomass2011

Could AAEM Influence Char

Formation During Lignin Pyrolysis?

• Thermally stable salts shown to substantially reduces the catalytic activity of AAEM during pyrolysis.

• Thermally unstable salts increase production of phenolic monomers

• Thermally stable salts have little to no effect on lignin pyrolysis

• We hypothesize that (thermally unstable) AAEM found in biomass contributes to the relative ease of pyrolyzing the lignin contained in the biomass compared to pure lignin pyrolysis

Footer goes here24

tcbiomass2011

Circumstantial Evidence That AAEM Plays

an Important Role in Lignin Pyrolysis

Top: Photos of char from

attempting to pyrolyze lignin in a

fluidized bed reactor (Nowakowski

et al., 2011)

Bottom: Agglomerated bed after

a test with sulfuric acid pretreated

red oak and resulting char

fragments

Footer goes here25

tcbiomass2011

Conclusions

• Vinyl phenols are very reactive and contribute to

formation of lignin oligomers

• Acids tend to catalyze the polymerization of phenolic

monomers in the vapor phase

• Alkali and alkaline earth metals (AAEM) inherent in

biomass appear to have significant effects on lignin

pyrolysis

• Thermally stable AAEM salts significantly reduce release

of phenolic monomers during pyrolysis

Footer goes here26

tcbiomass2011

Acknowledgments

• ConocoPhillips Company’s sponsorship of this study

• CSET staff – Patrick Johnston, Marge Rover, Sunitha

Sadula, Ryan Smith

• Fellow graduate students at CSET

• CSET undergraduate hourly research assistants

Footer goes here27

tcbiomass2011

Footer goes here28

tcbiomass2011

References

Amen-Chen, C., H. Pakdel, et al. (2001). "Production of monomeric phenols by thermochemical

conversion of biomass: a review." Bioresource Technology 79(3): 277-299.

Bayerbach, R. and D. Meier (2009). "Characterization of the water-insoluble fraction from fast

pyrolysis liquids (pyrolytic lignin). Part IV: Structure elucidation of oligomeric molecules." Journal of

Analytical and Applied Pyrolysis 85(1-2): 98-107.

J. Piskorz, P. M., D. Radlein (1999). Pyrolysis of Biomass - Aerosol Generation: Properties,

Applications, and Significance for Process Engineers. Biomass - A Growth Opportunity in Green

Energy and Value-Added Products. R. P. O. a. E. Chornet. Oakland, California, Elsevier Science

Ltd. 2: 1153-1167.

Mohan, D., C. U. Pittman, et al. (2006). "Pyrolysis of Wood/Biomass for Bio-oil: A Critical Review."

Energy & Fuels 20(3): 848-889.

Mullen, C. A. and A. A. Boateng (2011). "Characterization of water insoluble solids isolated from

various biomass fast pyrolysis oils." Journal of Analytical and Applied Pyrolysis 90(2): 197-203.

Patwardhan, P. R. (2010). Understanding the product distribution from biomass fast pyrolysis.

Doctor of Philosophy, Iowa State University.

Pollard, A. J. S. (2009). Comparison of bio-oil produced in a fractionated bio-oil collection system.

Master of Science, Iowa State University.

USDOE (2004). Biomass Feedstock Composition and Property Database. U. S. D. o. Energy. 2011.

Wyman, C. (1996). Handbook on bioethanol: production and utilization, Taylor & Francis.

Footer goes here29

tcbiomass2011

Lignin Pyrolysis

> Organosolv corn stover lignin was obtained from Archer

Daniels Midland company

> Lignin was washed in 0.1N hydrochloric acid to remove

mineral impurities (>0.1% ash remaining) and subsequent

DI water washes

> The dried lignin was then impregnated with 1 wt% cation

in the form of potassium, sodium, magnesium, and

calcium acetate to represent common biomass cations

Footer goes here30

tcbiomass2011

Methodology

> A Frontier Laboratories PY-2020iS furnace type pyrolyzer

fitted with an A3-1020E autosampler was used for

analytical pyrolysis

> A Brucker 430-GC with an FID detector was used to for

quantification of select lignin pyrolysis products

> Select products were identified using an identical

instrument interfaced to an MS and were then checked on

the FID system with chemical standards

> GC column used was a VF-1701ms

> 0.25mm ID, 60 meter length

Footer goes here31

tcbiomass2011

Micropyrolyzer Setup

Pyrolysis II Proceedings - Gas Technology Institute NonAtmospheric, Non-catalytic Method for...

Documents

Transcript of Pyrolysis II Proceedings - Gas Technology Institute NonAtmospheric, Non-catalytic Method for...