Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
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