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2. Overview of Presentation1Introduction2Review of Literatures3Materials and Methods4Results and Discussions5 Conclusions 2 3. IntroductionLignocellulosics Plentiful supply & Renewable resources Comparatively low cost No competition with food and feed production Environmentally benign 3 4. Problem StatementIntroductionBackgroundObjectivesPotential sources Dedicated crops Invasive plants Agro-industrial waste4 5. Problem statement Introduction BackgroundObjectives Lignocellulosic Conversion Process Direct combustion Biogas (Gasification, Anaerobic digestion) Biofuels (Bioethanol, biomethanol, Fischer-Tropsch (FT) diesel, biobutanol,Biohydrogen)Conversion toHolocellulosemonomeric sugarsLignocellulosicsLigninConversion torenewableAdhesive, biodegradable fuel, chemicals or polymers, bioantioxidant, food 5 6. Lignocellulosics Lignocellulosics Application6 7. PretreatmentProblem statementBackgroundObjectives Important processing step in biomass conversion alter the structure of the biomass break the lignin seal disrupt the crystalline structure of cellulose (Adapted from Hsu et al., 1980).7 8. BackgroundIntroductionObjectivesMethods of pretreatment Methods Combinative pretreatment 8 9. Problem StatementProblem statement BackgroundObjectives Selection of feedstock (Composition, growthrequirement,productivity, land/watercompetition with foodor fodder, biomassnature and ease of delignication and pulp yield) Selection of pretreatment method (long list ofoptimized methods, difficult to choose)9 10. Problem Statement Rationale Background Objectives Molecular structure of constituentpolymers, especially lignin 10 11. Background ObjectivesObjectivesObjective 1 Objective 2Objective 3To compare theTo characterizeanddescribeTo evaluate thedelignification Typha lignin and effectofability of differentestablisharomaticprehydrolysis correlationcompounds inmethods and tobetween lignin organosolvstructure (S/G delignificationassess theratio) and ability ofeffectiveness ofdelignificationMiscanthuspretreatmentability11 12. Literature ReviewS.N. Feed-Pretreatment FindingsAuthor &Year stockmethod1. AspenAutohydrolysis & - Positive effect of aromatics in Wayman &solvent extraction delignification Lora, 19782. Bagasse Presoaking, - Better effect of prehydrolysisPatel & prehydrolysis+Varshney, 1989 organosolv delignification3. MxGDAP + Ethanol- Presoaking has better effectBrosse et al.,organosolv process on xylan recovery,2009 delignification and enzymatic digestibility4. MxGLignin - Description of two kinds of El Hage et al.,characterization lignin from MxG 20095. MxGAutohydrolysis + -Autohydrolysis enhanced theEl Hage et al.,OS delignification 2010 - Positive effect of 2-naphthol12 13. MATERIALS & METHODS PressureGuaze Reactor Heater Temp.Controller 13 14. Raw Materials Raw MaterialsPrehydrolysisOrganosolv Process Enzymatic HydrolysisLignin Separation & Characterizati Miscanthus x Giganteus energy dedicated crop Palm oil industryPerennial grassagricultural by-productNon invasive low costRequires no nitrogen / herbicide6 million tons /year in Malaysia Produces 20-25 tons /ha/year Typha capensis invasive grass fast growing , highly prolific (50-60 ton/ha/year) 15. OBJECTIVE 1To compare the delignification ability of differentprehydrolysis methods and to assess theeffectiveness of pretreatment Pulp yield EOL yield KL content of the pulp Total reducing sugar and glucose yield15 16. Raw MaterialsMaterials and Methods PrehydrolysisOrganosolv ProcessEnzymatic HydrolysisLignin Separation & Characterizati16 17. Raw Materials Materials and MethodsPrehydrolysisOrganosolv ProcessEnzymatic HydrolysisSecond step: Organosolv Delignification Lignin Separation & Characterizati17 18. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentEnzymatic hydrolysability1. Composition of untreated biomass Lignin Characterization 100Content (% extractive free dry wt basis) 9023.120.4 25.9 Lignin (%) 80 Hemicellulose (%) 70 Cellulose (%) 6026.728.538.4 50 40 30 47.448.4 2041.2100 MxG EFB Typha Feedstock Holocellulose extraction by sulphite Glucans and xylans: 75-80% delignification method Cellulose extraction by alkaline method Lignin: 20-25% (TAPPI) Lignin by difference Composition almost similar for all biomasses 18 19. CompositionComposition of Prehydrolysis untreated biomassCombinative pretreatmentEnzymatic hydrolysabilityLignin CharacterizationComposition after prehydrolysis Xylans hydrolysed and removed in large amount (Typha>EFB>MxG) Partial lignin removal Pulp rich in cellulose19 20. CompositionResults and DiscussionsPrehydrolysis Combinative pretreatment Enzymatic hydrolysability Lignin Characterization Lignin substantially removed Higher mass loss 20 21. Composition Results and Discussions Prehydrolysis Combinative pretreatment Enzymatic hydrolysability EOL & KL Content of the pulp after Lignin Characterizationorganosolv delignification EOL 18 KLPercentage (dry biomass basis)20.017161618.0 16 1416.0131214.0 12 12 11 12 1012.0 810.088 8716 7 8.0 6 5 66 55556 6 6.0 4.0 2 2.0 11 0.0MiscanthusEFBTypha Treatments Prehydrolysis step enhanced the subsequent delignification (destruction of lignin seal, easier delignification) DAP, SP & EP: not very efficient (significant delignification of EFB in DAP) Naphthol : positive effect for MxG and EFB; no effect in Typha Typha has different behaviour; easier to delignify even with single step pretreatment.21 22. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentMxG: Yield of total reducing sugars and glucose Enzymatic hydrolysabilityLignin Characterization70 61Reducing sugar5860Glucose 52 50495045 44 Sugar content (%)39403833 29 3030 28252420 15 11106 73 0 RM_M DAP AHN SP OS DAP+OS AH + OSEP + OSAHN + OSSP+OS Treatments low hydrolysability after prehydrolysis low hydrolysability after organosolv alone (performed at low severity, low conc. of sulfuric acid, low temperature..) hydrolysability enhanced after combinative treatment. Organosolv is necessary because it removes a large part of lignin and make cellulose more accessible22 23. CompositionResults and DiscussionsPrehydrolysis Combinative pretreatmentEFB: Yield of total reducing sugars and glucoseEnzymatic hydrolysability Lignin Characterization 7064 Reducing sugar61 60 Glucose 54 50 49 5044 Sugar content (%) 39 40 34 33 323229 30 27 262422 22 19 20 10 105 0 RM_E DAPAHNSP OS DAP+OSAH + OSEP + OS AHN + OS SP+OS Treatments good correlation was observed between Lignin content & hydrolysability Dilute acid prehydrolysis+Organosolv process showed best result.23 24. CompositionResults and Discussions PrehydrolysisCombinative pretreatmentTypha: Yield of total reducing sugars and glucose Enzymatic hydrolysabilityLignin Characterization 70 Reducing sugar 60 61 59 60Glucose575853 50 46454342 4343 41 Sugar content (%) 3939 40 36 3534 3429 3027 21 2013 106 0 Typha demonstrated different behaviourTreatments Good hydrolysability after the prehydrolysis even if the KL content in the pulp are high Reactivity toward enzyme only slightly improved after OS Typha is easier to delignify, one step process showed tantamount effect No effect of naphthol on delignification ability24 25. OBJECTIVE 2To characterize and describe Typha lignin andestablish correlation between lignin structure (S/Gratio) and delignification ability FTIR Major peak assignment & NMR description GPC Relative amount of constituentmoieties (S/G ratio) Mn, Mw & PI 25 26. Raw Materials Materials and Methods Prehydrolysis Organosolv Process Enzymatic Hydrolysis Lignin Separation & CharacterizatiLignin Isolation 26 27. Raw Materials Materials and Methods Prehydrolysis Organosolv Process Enzymatic Hydrolysis Lignin Separation & CharacterizatiLignin characterization Two fractions of lignin analysed (CEL & EOL) Spectroscopic methods (FTIR & NMR) Chromatographic method (GPC) 27 28. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentEnzymatic hydrolysabilityLignin CharacterizationLignin polymer Lignin is a complex natural polymercomprised of p-hydroxyphenyl (H),guaiacyl (G) and syringyl (S) units (S/G) ratio- important characteristic(because G has high tendency torecondensed >> delignification moredifficult) HG S Adapted from Wershaw, 200428 29. Composition Results and Discussions Prehydrolysis Combinative pretreatmentFTIR spectra of Typha CEL Enzymatic hydrolysability Lignin Characterization70,5 65 - 1515.9 G+S - 1329.5 S 602065,0 - 1240 G 55 3854,3 - 1166.8 typical of 50 3821,4 HGS lignin - 1125.9S 452341,5 - 1033.8 G 2360,0 40 - 834.7 G+S 35%T 30 251166.8 20 834,7668,3 15 1369,4605,6527,5 101125,92933,81240,11729,95 3412,1 1329,51033,81515,9 1604,61457,3 360032002800 24002000 18001600 140012001000800 600 400,0Wavelength (cm-1) H-G-S lignin (usual for herbaceous crop)29 30. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentFTIR Peak assignment for Typha CELEnzymatic hydrolysabilityLignin Characterization - 1515.9 G+S - 1329.5 S - 1240 G - 1166.8 typical of HGS lignin - 1125.9S - 1033.8 G - 834.7 G+S30 31. Composition Results and Discussions PrehydrolysisCombinative pretreatmentNMR spectra of Typha CEL Enzymatic hydrolysability Lignin Characterization Presence of residual sugars (peaks at 95-100ppm & 70-75ppm) High Acetylation content: 0.44 acetate group/aryl (0.06 for Miscanthus) Low paracoumaryl content : 0.01 PC group/aryl (0.1 for MxG) S/G/H= 55/15/30 Very high S/G ratio (3.7) High S/G ratio support the easier delignification (Del Ro et al., 2005) 31 32. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentNMR spectra of Typha CEL (A) & EOL (B)Enzymatic hydrolysabilityLignin Characterization Comparison Typha EOL and CEL EOL non sugar (peaks at 95- 100ppm + 70-75ppm) propyl side chain shows deconstruction of -O-4 linkage (60-90ppm) Acetate extensively 153 147 hydrolysed during organosolv hydrolysis In EOL, S etherified (153ppm is very low but S non etherified (147ppm) very high extensive depolymerization through aryl ether bond cleavage.32 33. Comparison of lignin from three feedstocks 33 34. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentSEC analysis of Typha CEL and EOLEnzymatic hydrolysabilityLignin Characterization LigninMwMn PI=Mw/Mn EOL456728771.59 CEL926841092.26 Higher molecular weight and polydispersity index of CEL Cleavage of aryl ether bonds & formation of smaller fragments during organosolv process Agreed with NMR results 34 35. Composition Results and DiscussionsPrehydrolysisCombinative pretreatmentSEC analysis of Typha CEL and EOLEnzymatic hydrolysabilityLignin Characterization LigninMwMn PI=Mw/Mn CEL926841092.26 Higher molecular weight and polydispersity index of CEL Cleavage of aryl ether bonds & formation of smaller fragments during organosolv process Agreed with NMR results 35 36. OBJECTIVE 3To evaluate the effect of aromatic compounds inorganosolv delignification ability of Miscanthus2-naphthol p- cresol o-cresol EOL yield Klason lignin hydroquinone content of the pulp Acid soluble lignin dihydroxyanthraquinone 36 37. Raw MaterialsMaterials and MethodsPrehydrolysis Organosolv Process Enzymatic Hydrolysis Lignin Separation & Characterizati 10 g ODW MiscanthusMixed with 0.4 g aromatics and soaked in 100 mL acetone overnight Acetone evaporation by air drying Autohydrolysis (1500C, 8h, S/L=1:9)OS delignification (1700C, 1h, SA=0.5%, S/L=1:8) Filtration Liquid EOLphaseKL Pulp 37 38. Effect of aromatics on delignification30EOL yield (% )KL (%)25Yield (%)2015105 13.3 14.9 20.8 5.9 16.8 7.3 23.4 3.817.8 8.322 4.80ControlNaphtholo-Cresolp-Cresol Hydroquinone DHAqTreatments38 39. Effect of aromatics on delignification 39 40. Scavenging action of aromaticspath 1 occurs if the blueFor feedstocks with the fragment is a G unitlow G content, path 0 is(more reactive). >>favoured Path 0 important for MxG 40 41. Conclusions Despite a very similar chemical composition, three biomassesdemonstrated different behavior during pretreatment. Typha was easier to delignify; one step pretreatment (prehydrolysis ordelignification) process was sufficient to break the lignin seal andrelease the sugars for enzymatic action. The combinative pretreatmentnot necessary The first step of pretreatment (i. e. prehydrolysis) significantly enhancethe efficacy of the second step of delignification of MxG and EFB andenzymatic hydrolysability also. DAP plus OS pretreatment resulted intobest results for EFB. Autohydrolysis in presence of naphthol plus OSpretreatment (AHN) is best for MxG. The treatment of biomass with a catalytic amount of aromaticcompounds like 2-naphthol during autohydrolysis exhibited asubstantial effect on both MxG and EFB delignification as well as onenzymatic hydrolysability. 41 42. Conclusions Typha lignin is of H-G-S nature as usual to other herbaceous plants butwith high S/G ratio suggesting its easier delignification Addition of catalytic amount of aromatic scavengers enhanceddelignification substantially (2-naphthol,p-cresol anddihydroxyanthraquinone with tantamount effect) a better knowledge of biomass at the molecular level allow a betteroptimization of pretreatment 42 43. Recommendations Obnoxious Typha an interesting guinea-pig for tropicalbiorefinery sector. Additional research for its valorizationessential. Experimentation on effect of additional aromaticscavengers in various feedstocks essential. 43 44. INDEBTED TOSDCC / AIT France Network44 45. Think global, act local GREENPROCESSGreen EnergyGreen WorldTHANKS FOR YOUR ATTENTION!!!
