C Hydrolysis and Fractionation of Hot-Water Wood Extracts Thomas E. Amidon Christopher D. Wood, Jian Xu, Yang Wang, Mitchell Graves and Shijie Liu Biorefinery Research Institute Department of Paper and Bioprocess Engineering SUNY College of Environmental Science and Forestry
Outline Introduction C Hydrolysis Membrane Separation / Concentration Conclusion
Introduction C Chemical components of wood 21% hardwoods 25% softwoods Lignin wood extractives 2-8% carbohydrates 35% hardwoods 25% softwoods hemicellulose cellulose 45%
Lignin Three precursors C a. trans-coniferyl b. trans-sinapyl c. trans-p-coumaryl alcohol alcohol alcohol Guaiacyl Syringyl p-hydroxyphenyl
Hemicellulose C Common among angiosperm woody biomass:
Hemicellulose Type Soft wood C Hard wood 1 5 ~ 8% 0 2 10~15% 0 3 0 2 ~ 5 4 7 ~ 10% Trace 5 Trace 15~30%
Cellulose C
Experimental Set-up: Extraction C
Maple Wood Extract C Acetic Acid, Methanol Acetyl, Polysaccharides Aromatics, Furfurals Monomeric Sugars Concentration, mm Methanol, mm 100 10 1 0.1 20 time, min. 0 50 100 150 200 Acetyl Aromatics Furfurals Starting conditions: 369.20 g OD Maple Woodchips 3024.04 g water, 28 C HAc MeOH 10 10 0 Sugars 0 0 50 100 150 200 time, min. 40 30 20 Acetic Acid, mm
ESF Biorefinery: Hot-Water Extraction Hydrolysis Fractionation Acetic Acid Methanol Reducing Sugars Aromatics, Furfurals Xylan C Fermentation to Ethanol, Plastics,
Biorefinery C Woodchips Hot-Water Extraction Residual Chips Wood Extracts Alkaline Pulping or Oxidation Separation / Hydrolysis Unbleached Pulp Pulping Chemicals Hydrolysis/ Saccharification Bleaching Black Liquor Bleached Pulp Separation/Co-generation Paper, Board, or Cellulose Products Carbohydrates Lignin Xylan Methanol Sugars Fermentation Acetic Acid Aromatics Ethanol Butanol Bioplastics
Hydrolysis C Extract or Dissolved woody biomass solution Dissolved carbohydrates and lignin in liquid Monomeric sugars (~1/3) and polysaccharides Hydrolyzate Monomeric sugars (> 80% of all carbohydrates) Hydrolysis
Hydrolysis C Depolymerize macromolecules (of carbohydrates) by inserting water molecules between the monomeric units Enzymatic hydrolysis Using a hydrolytic enzyme as catalyst Acid Hydrolysis Using acid (proton) as catalyst
Enzymatic Hydrolysis C Substrate specific Cellulase, xylanase, Endo, exo, Inhibition Acid phenolics
Enzymatic Hydrolysis C Three xylanase strains obtained from Geneco Standard activities measured (hydrolysis of Oat Xylan) ph buffer: Na 2 HPO 4 Citric acid Xylanase Acitivity, U/ml 400 300 200 100 0 B C D 3 4 5 6 7 ph
Enzymatic Hydrolysis C No ph adjustment Reducing Sugar Concentration, g/l 60 50 40 30 ph = 3.26 0 1 2 3 4 B C D Hydrolysis Time, Days
Enzymatic Hydrolysis C Reducing Sugar Concentration, g/l 60 50 40 30 ph = 5.5 0 1 2 3 4 Hydrolysis Time, Days B C D
Enzymatic Hydrolysis C Reducing Sugar Concentration, g/l 60 50 40 30 ph = 7 0 1 2 3 4 Hydrolysis Time, Days B C D
Acid Hydrolysis C Glycosidic bonds Proton is the active catalyst No preference on first, second, or any bond Dehydration Undesirable dehydration reactions with monomeric sugars as initial reactants Acid recover / reuse
Acid Hydrolysis C Dehydration reaction Reaction Rate Hydrolysis Reaction [H + ]
Acid Hydrolysis Dilute acid Lower ph, but not high concentration HCl, H 2 SO 4, HNO 3, C Furfural, HMF and further dehydration products Lignin / aromatics - deposition
Acid Hydrolysis: 95 C C Xylose Concentration, g/l 70 60 50 40 30 20 10 0 0% H 2 SO 4 1% H 2 SO 4 2% H 2 SO 4 4% H 2 SO 4 0 60 120 180 Time at temperature, minutes
Acid Hydrolysis: 105 C C Free Acetic Acid Concentration, g/l 10 8 6 4 2 0 0% H 2 SO 4 1% H 2 SO 4 2% H 2 SO 4 4% H 2 SO 4 0 20 40 60 80 100 120 Time at temperature, minutes
Hydrolysis: 105 C C 10 0% H 2 SO 4 Precipitates, g/l 8 6 4 2 1% H 2 SO 4 2% H 2 SO 4 4% H 2 SO 4 0 0 20 40 60 80 100 120 Time at temperature, minutes
C
Experimental Set-up: Membrane Separation Biorefinery Research Institute C
Schematic Diagram C P Permeate Holding Tank Feed and Concentrate Tank
Membrane Separation C Resistances: Osmotic Pressure Friction Porous Solids Model: μ U Δp = π + U 1+ k a + U 2 2 bu
Flux versus Pressure C 500 Permeate Rate, ml/min 400 300 200 100 0 40 60 80 100 120 140 160 Pressure, PSI
First pass: 3-15-06 C Permeate Rate, ml/min 500 400 300 200 100 V 0 = 66L V f = 27.12L [HAc] 0 : 5.01 g/l [HAc] f : 6.09 g/l P = 150 psi 0 0 2000 4000 6000 8000 10000 12000 Time, second
Second pass: 3-15-06 C 300 Permeate Rate, ml/min 250 200 150 100 50 0 V 0 = 66.12 L V f = 29.94 L [HAc] 0 : 2.50 g/l [HAc] f : 3.42 g/l P = 150 psi 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 V 0 /V
Third Pass: 3-15-06 C 300 Permeate Rate, ml/min 250 200 150 100 50 0 V 0 = 65.94 L V f = 22.82L [HAc] 0 : 1.55 g/l [HAc] f : 2.22 g/l P = 150 psi 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 V 0 /V
First pass: 3-14-06 C Permeate Rate, ml/min 500 400 300 200 100 V 0 = 66L V f = 28L [HAc] 0 : 4.62 g/l [HAc] f : 5.19 g/l P = 150 psi 0 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 V 0 /V
Second pass: 3-14-06 C Permeate Rate, ml/min 300 200 100 0 V 0 = 66 L V f = 28 L [HAc] 0 : 2.20 g/l [HAc] f : 3.3 g/l P = 150 psi 1.0 1.2 1.4 1.6 1.8 2.0 2.2 V 0 /V
Third Pass: 3-14-06 C Permeate Rate, ml/min 400 300 200 100 V 0 = 66 L V f = 22.23 L [HAc] 0 : 1.40 g/l [HAc] f : 2.64 g/l P = 150 psi 0 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 V 0 /V
Osmotic Pressure Change C 160 140 120 100 π, psi 80 60 40 20 0 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 V 0 /V
Fractionation of wood extracts C Time, minutes 0 60 120 180 240 300 360 15 Xylose Total Monomeric Sugars C, g/l 10 5 Concentrate Stream 0 0.00 Permeate Stream 0.02 0.04 0.06 C, g/l 0.08 0.10 0 60 120 180 240 300 360 Time, Minutes
Reducing sugars as xylose: C 200 Starting point First pass - 23.4 g/l Second pass 18.2 g/l Reducing Sugars, g/l 150 100 50 0 1 2 3 4 5 6 7 8 9 10 11 12 V 0 /V
Acetyl C 40 30 Free Acetic Acid Bond Acetyl, as acetic acid C, g/l 20 10 0 1 2 3 4 5 6 7 8 9 10 V 0 /V
Minors C 1.6 1.4 C, g/l 1.2 1.0 0.8 0.6 Methanol HMF Furfural Formic Acid 0.4 0.2 0.0 1 2 3 4 5 6 7 8 9 10 V 0 /V
Conclusions C Wood Extracts contain more oligmors than monomeric sugars Acid hydrolysis is currently more suited NF-Membrane can be employed to separate acetic acid from sugars; The Osmotic pressure plays an important role; The cross-flow rate is proportional to the pressure drop; The cross-flow rate reduces as the membrane ages.
C Thanks!