Hemicellulose extraction from wood OSB strands

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DESCRIPTION

Extraction of wood components from OSB strands using hot water. A composition of the liquid phase (extract) is given for different extraction conditions. Mechanical properties of OSB panels made with the extracted wood are compared with standard panels.

Transcript

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Influence of Hemicellulose Extraction on Suitability for Oriented Strand Board

(OSB) Production

Rory H. Jaraa

Juan Paredesb

Adriaan van Heiningena

Stephen Shalerb

a Department of Chemicaland Biological Engineering

b Advanced Engineered Wood Composites Center

O

O

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OH

O-Ac

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OHO

COOH

OHOMe

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OOH

O-Ac

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Department of Chemical and Biological Engineering2

Outline

BackgroundObjectivesExperimental proceduresResults and discussionsConclusions

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COOH

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Department of Chemical and Biological Engineering3

OSB ProcessWood componentsChemical composition and wood strength

Background

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OH

O-Ac

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COOH

OHOMe

OH

OH

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OH

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Department of Chemical and Biological Engineering4

OSB ProcessBackground

O

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OH

O-Ac

OH

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OHO

COOH

OHOMe

OH

OH

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O-Ac

OH

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O-Ac

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Department of Chemical and Biological Engineering5

Log Hauling and SortingLadding

Debarking

Logs

StrandingScreening

Drying

Blending

Forming linePressing

Finishing lineShipping

HemicelluloseExtraction Process

Modified OSB Process

Sugar-basedpolymers

Sugar-basedchemicals

FurfuralXylitol

Ethanol

Background

PERFORMANCE ?

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OH

O-Ac

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OHO

COOH

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O-Ac

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Department of Chemical and Biological Engineering6

Wood ComponentsXylan

Glucomannan

Lignin

Cellulose

(M. Åkerholm and L. Salmén, STFI 2004)

Background

Hardwood (% o. d. wood)

Cellulosea 41.0 – 51.0Lignina 21.5 – 31.0Hemicellulosesa 20.0 - 34.5Ashb 0.2 - 1.0

Softwood (% o. d. wood)Cellulosea 33.0 – 42.0Lignina 27.0 – 32.0Hemicellulosesa 26.0 – 33.0Ashb 0.1 – 0.5

a Sjostron, E., 1993b Rowell, R., 2005

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OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

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O-Ac

OH

OOH

O-Ac

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Department of Chemical and Biological Engineering7

CelluloseGlucomannan

Lignin 1

XylanLignin 2

(Lawoko et al. Biomacromolecules 6(6) 3467-3473, 2005)

Wood ComponentsBackground

(Sweet et al. Holzforschung 53 (1999) 311-317)

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COOH

OHOMe

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Department of Chemical and Biological Engineering8

Chemical composition and wood strength

Background

Molecular level depends on individual components of the cell wall

Cellulose greatest polymeric chain and higher DP

Lignin is a nature’s adhesive. Hydrophobic polymer.

Cellulose and lignin are the main structural wood components. Hydrogen bonds are important for providing rigidity.

Hemicelluloses are a series of carbohydrate molecules with lowerDP than cellulose. They exhibit hydrogen bonding.

Early degradation of hemicelluloses affect the wood strength (Curling at al., Forest Products Journal, Vol. 52, No 78, 2002)

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O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering9

Issues to be consideredMechanical properties of OSB must be maintained after hemicellulose extractionThe extraction process must minimize degradation of both cellulose and lignin

Background

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O

OH

O-Ac

OH

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OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering10

Objective

• Determine how specific variables in the OSB strand extraction process (namely, pH, temperature, time and strand thickness) affect hemicellulose yields and characteristics of cellulose and lignin in the wood

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O

OH

O-Ac

OH

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OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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3 Experimental

Procedure

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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3

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Department of Chemical and Biological Engineering12

Wood material preparationRed Maple tree (hardwood)Stranding process at AEWC CenterWood material air-dried

Experimental Procedures

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OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

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Department of Chemical and Biological Engineering13

Lab ExtractionExperimental Procedures

Modified ASE-100Wood strands

Water

Filtrate(Hemicellulose Extract)

Solid Residue(Extracted strands)

Temperature: 140 – 170ºC

Time: 15 – 90 min

O

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O

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O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering14

Water Extraction

Solid Phase

Weight Loss(Oven Dried)

DMC Extraction

Liquid Phase(Solid Determ.) Hydrolysis (1º, 2nd)

HPAEC Analysis

Klason Lignin Cellulose

Liquid Phase

Centrifuge

2nd Hydrolysis

Undissolved Material

HPAEC Analysis

Klason Lignin

Cellulose Hemicelluloses

Solid Content(Freeze Drying)

Ash Content

Hemicelluloses

Ash Content

WOOD

Acid Sol. Lignin

Chemical analysis procedure

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O

OH

O-Ac

OH

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OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering15

Yield DeterminationExperimental Procedures

100* extraction before (o.d.) wood

extractionafter (o.d.) residue solid (%) Yieldsp =

100* extraction before (o.d.) wood

extract weight TotalS.C. (%) Yield fdlp ∗=

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering16

Results

Water extraction yieldMass BalanceOSB panels and physical/mechanical properties

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

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Department of Chemical and Biological Engineering17

Water Extraction - Yield vs Temperature

0.00

50.00

100.00

150.00

200.00

250.00

130 140 150 160 170 180

Temperature (ºC)

Yiel

d (m

g/g

woo

d)

From solid - 45 min From solid - 90 min From solid - 15 minfrom liquid - 45 min From liquid - 90 min From liquid - 15 min

Results: Water extraction yield

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

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Department of Chemical and Biological Engineering18

⎟⎟⎠

⎞⎜⎜⎝

⎛ −⋅=

75.14100][exp CTtR

o

O

Results: Water extraction yield

• Proposed for Overend and Chornet, 1987)

Severity Factor (Ro)

Where,

t: Time (minutes)

T: Temperature (ºC)

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OH

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OH

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OHO

COOH

OHOMe

OH

OH

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O-Ac

OH

OOH

O-Ac

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Department of Chemical and Biological Engineering19

Water Extraction - Yield vs Temperature

0.00

50.00

100.00

150.00

200.00

250.00

2.50 2.70 2.90 3.10 3.30 3.50 3.70 3.90 4.10 4.30 4.50

Severity Factor (Ro)

Yiel

d (m

g/g

woo

d)

From solid From liquid

Results: Water extraction yield

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

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O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering20

Results: Water extraction yield

Severity Effect on pH Extraction

R2 = 0.9535

R2 = 0.9857

3

3.2

3.4

3.6

3.8

4

4.2

4.4

4.6

4.8

5

2.50 2.70 2.90 3.10 3.30 3.50 3.70 3.90 4.10

Severity Factor (log(Ro))

pH

0.00

50.00

100.00

150.00

200.00

250.00

300.00

Yiel

d (s

.p.,

mg/

g w

ood

o.d.

)

pH Yield (from s.p.)

O

O

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OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering21

Results: Mass balance

Lignin removed from wood

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

2.60 2.80 3.00 3.20 3.40 3.60 3.80 4.00 4.20

Severity Factor (Log Ro)

Lign

in re

mov

ed (

% )

Precipitated Lignin (From Liquid)Klason Lignin (From Liquid)

Acid Soluble Lignin (From Liquid)

Total Lignin (From Liquid)

Total Lignin (From Solid)

O

O

O

O

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O

OH

O-Ac

OH

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OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering22

ResultsResults: Mass balance

Carbohydrates Mass Balance - Liquid Phase

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

2.6 2.8 3 3.2 3.4 3.6 3.8 4 4.2 4.4

Severity Factor (Log Ro)

Carb

ohyd

rate

con

tent

(% o

n or

igin

al

suga

r)

Arabinan Galactan Xylan Mannan Cellulose

O

O

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OH

O-Ac

OH

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OHO

COOH

OHOMe

OH

OH

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O-Ac

OH

OOH

O-Ac

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Department of Chemical and Biological Engineering23

ResultsResults: Mass balance

Carbohydrates Mass Balance - Solid Phase

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5

Severity Factor (Log Ro)

Carb

ohyd

rate

con

tent

(% o

n or

igin

al s

ugar

)

Arabinan Galactan Xylan Mannan

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering24

M ass Balance Hemicelluloses

0.00

20.00

40.00

60.00

80.00

100.00

120.00

140.00

160.00

2.50 2.70 2.90 3.10 3.30 3.50 3.70 3.90 4.10

Severity Factor (Log(Ro))

Suga

r (m

g/g

woo

d o.

d.)

Arabinan-L.P. Galactan-L.P . Xylan-L.P . Mannan-L.P.

Arabinan-S.P. Galactan-S.P. Xylan-S.P. Mannan-S.P.

Results: Mass balance

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

5

12

45

3

3

Department of Chemical and Biological Engineering25

Manufacture of OSB Panels

Pressure Indicator

Heat Exchanger

Pressure Safety SwitchVessel Vessel

Circulation Pump

Flow Control Valve

Pressure Release Valve

Drain Valve

Rupture DiskThermal Sensor (RTD)

Heat Exchanger

Cooling Water

Real Time Sampling

Dispersion Weight

Thermal Sensors (RTD)

Insulation

Basket Inside(To hold wood material)

Water extraction

Pilot scale

Conditions:

Temperature: 160ºC

Time: 45 – 90 min

Batch: 500 grs.

(Preheating: 50 min)

L / S: 6

Results: OSB Panels

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering26

Panel manufacturing was done at AEWC Center following internal procedures:

Weight: 1.28 kg

Adhesive: pDMI, 4% o.d.w.

Density: 38pcf, at 0% MC

Manufacture of OSB PanelsResults: OSB Panels

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

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Department of Chemical and Biological Engineering27

Results: OSB Panels

Physical PropertiesTests were done following ASTM D 1037 specifications.

Moisture Content Behavior

0

5

10

15

2025

30

35

40

45

Control SF-3.54 SF-3.81

Material Source

Moi

stur

e C

onte

nt (%

)

Conditioned2 Hours24 Hours

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

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Department of Chemical and Biological Engineering28

Thickness Swell Behavior

02468

101214

Control SF-3.54 SF-3.81

Material Source

Thic

knes

s Sw

ell (

%)

2 Hours

24 Hours

Water Absortion Behavior

05

101520253035

Control SF-3.54 SF-3.81

Material Source

Wat

er A

bsor

tion

(%)

2 Hours

24 Hours

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

5

12

45

3

3

Department of Chemical and Biological Engineering29

Results: OSB Panels

Mechanical PropertiesTests were done following ASTM D 1037 specifications.

Mechanical Properties

1

10

100

1000

10000

Control SF-3.54 SF-3.81

Material Source

Load

Fac

tors MOR (psi)

MOE (kpsi)

SPL (psi)

IB (psi)

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

5

12

45

3

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Department of Chemical and Biological Engineering30

ConclusionsExtraction with pure water

Degradation of cellulose is not significant

Xylan contribute significantly more to the total hemicellulose yield.

Continued hydrolysis of carbohydrates

Further research is necessary to understand changes in physical and mechanical properties of OSB

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

5

12

45

3

3

Department of Chemical and Biological Engineering31

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

5

12

45

3

3

Department of Chemical and Biological Engineering32

Results

Mass Balance

Cellulose = [Glucan – Mannan/1.7]/(wood weight)

Hemicellulose = Total Sugar/(wood weight) - Cellulose

Xylan = [Xylose*(132/150)+UA*0.6*(132/176)]

O

O

O

O

OO

O

OH

O-Ac

OH

O

OHO

COOH

OHOMe

OH

OH

OO

O-Ac

OH

OOH

O-Ac

123

4

5

12

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3

3

Department of Chemical and Biological Engineering33

MOR: Modulus of Rupture (Maximum Load)

MOE: Modulus of Elasticity

SPL: Stress at Proportional Limit

MOR

SPLMOE

Deflection (Strain)

Load

(Str

ess)

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