Hydrolysis and Fractionation of Hot-Water Wood Extracts

Transcription

1 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

2 Outline Introduction C Hydrolysis Membrane Separation / Concentration Conclusion

3 Introduction C Chemical components of wood 21% hardwoods 25% softwoods Lignin wood extractives 2-8% carbohydrates 35% hardwoods 25% softwoods hemicellulose cellulose 45%

4 Lignin Three precursors C a. trans-coniferyl b. trans-sinapyl c. trans-p-coumaryl alcohol alcohol alcohol Guaiacyl Syringyl p-hydroxyphenyl

5 Hemicellulose C Common among angiosperm woody biomass:

6 Hemicellulose Type Soft wood C Hard wood 1 5 ~ 8% ~15% ~ ~ 10% Trace 5 Trace 15~30%

7 Cellulose C

8 Experimental Set-up: Extraction C

9 Maple Wood Extract C Acetic Acid, Methanol Acetyl, Polysaccharides Aromatics, Furfurals Monomeric Sugars Concentration, mm Methanol, mm time, min Acetyl Aromatics Furfurals Starting conditions: g OD Maple Woodchips g water, 28 C HAc MeOH Sugars time, min Acetic Acid, mm

10 ESF Biorefinery: Hot-Water Extraction Hydrolysis Fractionation Acetic Acid Methanol Reducing Sugars Aromatics, Furfurals Xylan C Fermentation to Ethanol, Plastics,

11 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

12 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

13 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

14 Enzymatic Hydrolysis C Substrate specific Cellulase, xylanase, Endo, exo, Inhibition Acid phenolics

15 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 B C D ph

16 Enzymatic Hydrolysis C No ph adjustment Reducing Sugar Concentration, g/l ph = B C D Hydrolysis Time, Days

17 Enzymatic Hydrolysis C Reducing Sugar Concentration, g/l ph = Hydrolysis Time, Days B C D

18 Enzymatic Hydrolysis C Reducing Sugar Concentration, g/l ph = Hydrolysis Time, Days B C D

19 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

20 Acid Hydrolysis C Dehydration reaction Reaction Rate Hydrolysis Reaction [H + ]

21 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

22 Acid Hydrolysis: 95 C C Xylose Concentration, g/l % H 2 SO 4 1% H 2 SO 4 2% H 2 SO 4 4% H 2 SO Time at temperature, minutes

23 Acid Hydrolysis: 105 C C Free Acetic Acid Concentration, g/l % H 2 SO 4 1% H 2 SO 4 2% H 2 SO 4 4% H 2 SO Time at temperature, minutes

24 Hydrolysis: 105 C C 10 0% H 2 SO 4 Precipitates, g/l % H 2 SO 4 2% H 2 SO 4 4% H 2 SO Time at temperature, minutes

25 C

26 Experimental Set-up: Membrane Separation Biorefinery Research Institute C

27 Schematic Diagram C P Permeate Holding Tank Feed and Concentrate Tank

28 Membrane Separation C Resistances: Osmotic Pressure Friction Porous Solids Model: μ U Δp = π + U 1+ k a + U 2 2 bu

29 Flux versus Pressure C 500 Permeate Rate, ml/min Pressure, PSI

30 First pass: C Permeate Rate, ml/min V 0 = 66L V f = 27.12L [HAc] 0 : 5.01 g/l [HAc] f : 6.09 g/l P = 150 psi Time, second

31 Second pass: C 300 Permeate Rate, ml/min V 0 = L V f = L [HAc] 0 : 2.50 g/l [HAc] f : 3.42 g/l P = 150 psi V 0 /V

32 Third Pass: C 300 Permeate Rate, ml/min V 0 = L V f = 22.82L [HAc] 0 : 1.55 g/l [HAc] f : 2.22 g/l P = 150 psi V 0 /V

33 First pass: C Permeate Rate, ml/min V 0 = 66L V f = 28L [HAc] 0 : 4.62 g/l [HAc] f : 5.19 g/l P = 150 psi V 0 /V

34 Second pass: C Permeate Rate, ml/min V 0 = 66 L V f = 28 L [HAc] 0 : 2.20 g/l [HAc] f : 3.3 g/l P = 150 psi V 0 /V

35 Third Pass: C Permeate Rate, ml/min V 0 = 66 L V f = L [HAc] 0 : 1.40 g/l [HAc] f : 2.64 g/l P = 150 psi V 0 /V

36 Osmotic Pressure Change C π, psi V 0 /V

37 Fractionation of wood extracts C Time, minutes Xylose Total Monomeric Sugars C, g/l 10 5 Concentrate Stream Permeate Stream C, g/l Time, Minutes

38 Reducing sugars as xylose: C 200 Starting point First pass g/l Second pass 18.2 g/l Reducing Sugars, g/l V 0 /V

39 Acetyl C Free Acetic Acid Bond Acetyl, as acetic acid C, g/l V 0 /V

40 Minors C C, g/l Methanol HMF Furfural Formic Acid V 0 /V

41 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.

42 C Thanks!