Characterizing Lignocellulosics Characterizing Lignocellulosics g gfrom MiscanthusCellulose - Lignin

g gfrom MiscanthusCellulose - LigninCellulose LigninCellulose Lignin

Poulomi SannigrahigA.J. Ragauskas

School of Chemistry and BiochemistrySchool of Chemistry and BiochemistryGeorgia Institute of Technology

Agro-energy feedstock: Miscanthusg gy

Perennial crop Perennial cropGrows to 11-14 ft in height/year

High biomass yields High biomass yieldsC4 grass with high rate of carbon fixation14 17 t / ( t 27 t / i t i l )14 – 17 tons/acre (up to 27 tons/acre in trials)Crop stands survive 25-30 years without

significant loss in biomass yieldssignificant loss in biomass yields

Presently used in Europe for power and heat tigeneration

Biomass to Bioethanol2

Moisture and Ash content

Moisture content of air dried Moisture content of air dried miscanthus sawdust (6 mm)4 6%4.6%

Ash contentMe ed b mped he ting to 525Measured by ramped heating to 525 °C in a muffle furnace

2 2%2.2%Higher than Loblolly pine (0.2 %) &

sweetgum (0 8 %)sweetgum (0.8 %)

Biomass to Bioethanol3

Elemental analysisyMeasured on 0.05 mm ground samples using elemental micro analyzer

60.0

50.0

40.0 MiscanthusSweetgumLoblolly Pine

30.0

Wt.%

10 0

20.0

0.0

10.0

Biomass to Bioethanol4

0.0C H O N

Inorganic elementsg

Analyzed in 6 mm ground samples Analyzed in 6 mm ground samples Acid digestion followed by ICP-emission

spectroscopyspectroscopy Coulometric method for total halogen

(Cl B I)(Cl+Br+I)

Biomass to Bioethanol5

Inorganic elementsg

340 0

360.0

380.0

280.0

300.0

320.0

340.0

MiscanthusSweetgumL.Pine

200 0

220.0

240.0

260.0

) o.d

. wei

ght

L.Pine

140.0

160.0

180.0

200.0

onte

nt (m

g/K

g)

60 0

80.0

100.0

120.0Co

0.0

20.0

40.0

60.0

Biomass to Bioethanol6Ba Cu Fe Na P Si

Inorganic elementsg

2000.0

1750.0

ght)

Miscanthus

1250.0

1500.0

en d

ried

wei

g MiscanthusSweetgumL.Pine

750 0

1000.0

ent (

mg/

Kg

ove

500.0

750.0

Con

te

0.0

250.0

Biomass to Bioethanol7Ca K Mg S Mn Cl+Br+I

Acid soluble and insoluble ligning Klason ligninA id i l bl li i i l t d i NREL th dAcid insoluble lignin isolated using NREL methodsExtractive free (40 mesh) sample hydrolyzed using 72

% H SO% H2SO4

Acid soluble ligninMeasured using UV-vis spectrophotometerCalculated from absorption at 205 nm

Biomass to Bioethanol8

Lignin content and compositiong

CH

CH2OH

CH

CH2OH

CH

CH2OH

Klason lignin

26

CH

CH

1CH

CH

126

CH

CH

126

Klason lignin Miscanthus: 25 %Loblolly pine: 29 %Sweetgum: 26 %

CH3OOH

3

4 OCH35

OH

3

45

OH

3

4 OCH35

Sweetgum: 26 %

A id l bl li i

SW x xGuaiacyl Syringyl p-Coumaryl

OHAcid soluble ligninMiscanthus: 1.1 %Loblolly pine: 0.5 %Sweetgum: 2 6 %

HW x x xGrass x x x

Sweetgum: 2.6 %

Biomass to Bioethanol9

Carbohydrate analysisy y

40 mesh extractive free 40 mesh extractive free wood

Hydrolyzed with 72 % y yH2SO4

Diluted to 3% H2SO4and autoclaved at 121°C for 1 hourS d i Sugars measured using HPLC with pulsed amperometric detectoramperometric detector

Biomass to Bioethanol10

Carbohydrate profiley55.0

60.0O

OH

OH

HOOH

45.0

50.0

teria

l

OH

35.0

40.0

tart

ing

mat

MiscanthusSweetgumL.Pine

O

20 0

25.0

30.0

wei

ght o

f s

OOHOH

OHCH2OH

O

OH

OH

OHOH

CH2OH

10 0

15.0

20.0

% d

ry w

OOH

HO

HOOH

O

OH

OH OHOH

CH2OH

0.0

5.0

10.0

OH

HO

Biomass to Bioethanol11Arabinose Galactose Glucose Xylose Mannose

Solid-state 13C NMR of miscanthus

Cellulose HemicelluloseLigninLignin LigninR-COCH3

g-OCH3

gC=O

gPhenolic

Biomass to Bioethanol12

Cellulose extraction

Holocellulose = Cellulose + Hemicellulose Holocellulose Cellulose + HemicelluloseObtained by treating extractive free wood

repeatedly with acetic acid and sodium chloriterepeatedly with acetic acid and sodium chloriteYield: 74% (by dry wt. of miscanthus)

Cellulose CelluloseBoil holocellulose with 2.5 M HCl at

100 °C for 4 hours100 C for 4 hoursYield: 55%

(by dry wt of holocellulose)(by dry wt. of holocellulose)

Biomass to Bioethanol13

Cellulose structure and crystallinityy ySolid-state 13C CP/MAS NMR of celluloseCellulose structure and crystallinityCellulose structure and crystallinity

C2,3,5O

O

CH 2O H

O

O HO H

6

4

2

1

1

C1

O H

OO H O

CH 2O H3

1

C4

C1

C6

Biomass to Bioethanol14

Cellulose structure and crystallinityy yDegree of crystallinity : 48.9 %Loblolly pine:63 %; Sweetgum: 53 3%Loblolly pine:63 %; Sweetgum: 53.3%

Crystalline + para crystalline Amorphousy p y p

Biomass to Bioethanol15

Milled wood ligning

Purest form of lignin Purest form of lignin that can be isolated

Wood extracted with ethanol and ethanol/benzene

Milled for 130 hours Extracted with 96%

Di f 48 hDioxane for 48 hours Dioxane collected, dried

and lignin purifiedand lignin purified

Biomass to Bioethanol16

Milled wood lignin – 13C NMRg

CH

CH

1

CH2OH

CH

CH

1

CH2OH

CH

CH

1

CH2OH

12

3

4

6

OCH35

CH3O

2

3

4

6

OCH35

1 12

3

4

6

5

OH OH OH

Guaiacyl (g) Syringyl (s) p-Coumaryl (h)

4 O 5

-OCH3

α-CO/ β-O-4

4-O-5

β-5s and g h-4

COOR

Biomass to Bioethanol17

Lignin molecular weight g g

Lignin acetylated and Mn Mw D Lignin acetylated and dissolved in THF

Molecular weight Miscanthus 8.33e3 1.38e4 1.65

gdistribution measured using gel permeation h t h

Sweetgum 9.41e3 1.6e4 1.70

L.Pine 7.58e3 1.34e4 1.77chromatography

Biomass to Bioethanol18

Thank You!

Biomass to Bioethanol19