Classifications

• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
  • C12P19/00—Preparation of compounds containing saccharide radicals
  • C12P19/02—Monosaccharides
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
  • C07C51/42—Separation; Purification; Stabilisation; Use of additives
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C53/00—Saturated compounds having only one carboxyl group bound to an acyclic carbon atom or hydrogen
  • C07C53/02—Formic acid
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C59/00—Compounds having carboxyl groups bound to acyclic carbon atoms and containing any of the groups OH, O—metal, —CHO, keto, ether, groups, groups, or groups
  • C07C59/185—Saturated compounds having only one carboxyl group and containing keto groups
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
  • C12P19/00—Preparation of compounds containing saccharide radicals
  • C12P19/14—Preparation of compounds containing saccharide radicals produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase, e.g. by cellulase, hemicellulase
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
  • C12P7/00—Preparation of oxygen-containing organic compounds
  • C12P7/02—Preparation of oxygen-containing organic compounds containing a hydroxy group
  • C12P7/04—Preparation of oxygen-containing organic compounds containing a hydroxy group acyclic
  • C12P7/06—Ethanol, i.e. non-beverage
  • C12P7/08—Ethanol, i.e. non-beverage produced as by-product or from waste or cellulosic material substrate
  • C12P7/10—Ethanol, i.e. non-beverage produced as by-product or from waste or cellulosic material substrate substrate containing cellulosic material
• • C—CHEMISTRY; METALLURGY
  • C13—SUGAR INDUSTRY
  • C13K—SACCHARIDES OBTAINED FROM NATURAL SOURCES OR BY HYDROLYSIS OF NATURALLY OCCURRING DISACCHARIDES, OLIGOSACCHARIDES OR POLYSACCHARIDES
  • C13K1/00—Glucose; Glucose-containing syrups
  • C13K1/02—Glucose; Glucose-containing syrups obtained by saccharification of cellulosic materials
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
  • D21C3/00—Pulping cellulose-containing materials
  • D21C3/04—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
  • D21C3/00—Pulping cellulose-containing materials
  • D21C3/20—Pulping cellulose-containing materials with organic solvents or in solvent environment
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
  • D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
  • D21C5/005—Treatment of cellulose-containing material with microorganisms or enzymes
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
  • C12P2201/00—Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis
• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
  • C12P2203/00—Fermentation products obtained from optionally pretreated or hydrolyzed cellulosic or lignocellulosic material as the carbon source
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E50/00—Technologies for the production of fuel of non-fossil origin
  • Y02E50/10—Biofuels, e.g. bio-diesel

Definitions

• the invention relates to a formic acid-based process for the preparation of levulinic acid from biomass while simultaneously producing formic acid and, if desired, cellulose, sugars (glucose) and bioethanol.
• Levulinic acid is a valuable raw material in the chemical industry, and its preparation from biomass has lately aroused a great deal of interest. Producing levulinic acid from the cellulose in biomass simultaneously produces formic acid according to the following reaction:
• Dissertation Girisuta B Levulinic Acid from Lignocellulosic Biomass, University of Groningen, 5 November 2007, pages 7 to 13, describes several known processes for preparing levulinic acid from biomass.
• the prepa- ration is usually done by acid catalysis.
• the acid used is typically a mineral acid, such as sulphuric acid, hydrochloric acid or hydrobromic acid.
• Page 11 Page 11 , second paragraph, of the dissertation describes a process, in which corn cob residue obtained from the production of furfural is used as raw material. Sulphuric acid and water are added to the residue stream (amount of raw material 21 % by weight and acid content 3% by weight). The reaction temperature is 169°C and a typical reaction time is 2 h. Non-dissolved humines are filtered and the levulinic acid extracted with methyl isobutyl ketone. After this, the water-acid mixture is recirculated to the reactor, levulinic acid and methyl isobutyl ketone separated, the latter returned to extraction and levulinic acid concentrated and purified by vacuum distillation. The levulinic acid yield is 19.9 % of the dry raw material.
• Page 11 , second paragraph, and page 12 of the dissertation describes the preparation of levulinic acid from corn starch by adding sulphuric acid and water and passing the thus obtained pulp through a double-screw extruder (temperature profile 80 to 100°C, 120 to 150°C and 50°C). After this, the humines are filtered and levulinic acid recovered from the filtrate in the same manner as described above.
• the levulinic acid yield is approximately 48% by weight.
• Producing levulinic acid by mineral acid-catalysed processes from biomass has the disadvantage, for instance, that acid concentrations are low and, correspondingly, water amounts are large. The amount of water to be separated is thus large.
• the recovery of the formic acid formed in the reaction from the product stream of the mineral acid-catalysed levulinic acid is also expensive and requires several process steps.
• the organic phase and water phase are separated, formic acid is separated as an at least 50% solution from the organic phase by distillation and levulinic acid (or le- vunate salt) is separated from the organic phase.
• levulinic acid or le- vunate salt
• furfural is separated from the organic phase, if desired.
• Another object of the invention is to aim at a process, in which the necessity of separating water is minimized in the production of levulinic acid.
• Yet another object of the invention is to aim at a cooking process that would be as self-supporting as possible in relation to cooking chemicals, especially formic acid.
• One object of the invention is also to combine the preparation of glucose and levulinic acid in an advantageous manner in a formic acid-based cooking process of biomass, in which the above-mentioned disadvantages that relate to the preparation of levulinic acid and glucose in known processes are avoided.
• the invention is based on producing levulinic acid in a formic acid-based cooking process of biomass through a formic acid catalysis at formic acid contents that are advantageous for water separation.
• levulinic acid production a molecularly equivalent amount of formic acid is formed and can be utilized as cooking chemical in the process.
• the process of the invention provides the advantage that the use of extra inorganic catalysts and extraction agents is avoided in the production of levulinic acid.
• formic acid is produced, whereby extra formic acid does not need to be added to the process. Because it is possible to use high acid contents in comparison with inorganic acid catalysts, the need for water separation is also reduced.
• the cellulose obtained in a formic acid-based cooking process of biomass is only partially hydrolysed into glucose, and the non-hydrolysed cellulose is led to the preparation of levulinic acid. It was found that most of the cellulose can be hydrolysed with only a small proportion of the enzyme requirement needed for a complete hydrolysis.
• Levulinic acid is prepared through a formic acid catalysis at formic acid contents that are advantageous for water separation. In levulinic acid production, a molecularly equivalent amount of formic acid is formed and can be utilized as cooking chemical in the process. This way, in the process of the invention, both high enzyme dosages in the enzymatic hydrolysis and formic acid losses in formic acid cooking are avoided. At the same time, levulinic acid is produced.
• Figure 1 shows an embodiment of the invention as a process chart (process chart 1 ) for the production of levulinic acid and, at the same time, formic acid from biomass in a formic acid-based cooking process.
• process chart 1 for the production of levulinic acid and, at the same time, formic acid from biomass in a formic acid-based cooking process.
• sugars (glucose) are also produced as well as bio- ethanol from them.
• Figure 2 shows another embodiment of the invention as a process chart (process chart 2) for the production of glucose, levulinic acid and, at the same time, formic acid from biomass in a formic acid-based cooking process.
• Figure 3 is a graphical representation of the effect of the enzyme dosage on the glucose yield in the embodiment of example 2.
• Figure 4 is a graphical representation of the effect of the enzyme dosage on the glucose yield in the embodiment of example 3.
• the invention relates to a process for the production of le- vulinic acid and formic acid and, if desired, cellulose, a sugar product and/or bioethanol from biomass in a formic acid-based cooking process.
• the process is characterised in that it comprises the following steps:
• step (f) if desired, recovering part of the cellulose pulp obtained in step (a) or leading it to enzymatic hydrolysis to produce a sugar product and to fermentation to produce bioethanol.
• the invention relates to a process for the preparation of cellulose, a sugar product and/or bioethanol from biomass in a formic acid-based cooking process, while simultaneously producing levulinic acid and formic acid and wherein the process contains the following steps:
• step (f) washing a second part of the cellulose pulp obtained in step (a) with water and recovering it or, if desired, leading it to enzymatic hydrolysis to produce a sugar product and to fermentation to produce bioethanol.
• the preparation step (b) of levulinic acid is performed in one step under the following conditions:
• the preparation step (b) of levulinic acid is performed in two steps,
• reaction time 1 to 10 min, preferably 2 to 6 min,
• the process of the invention may also contain between steps (a) and (b) a step (aO), in which the cellulose pulp intended for step (b) is washed with water or a formic acid solution so that the formic acid content of the cellulose pulp is 20 to 60% of dry pulp.
• aO a step in which the cellulose pulp intended for step (b) is washed with water or a formic acid solution so that the formic acid content of the cellulose pulp is 20 to 60% of dry pulp.
• One embodiment of the invention relates to a process, in which from the water wash of step (f) a formic acid solution is recovered as a washing filtrate and used in step (aO) to wash the cellulose pulp.
• molecularly the same amount of levulinic acid is formed as the amount of make-up formic acid returned to the process.
• the formic acid used in the cooking step (a) may also contain acetic acid.
• a formic acid solution is recovered as a wash filtrate from step (aO), formic acid is then separated from it and returned to the cooking step (a).
• the invention relates to a process for producing glucose, levulinic acid and formic acid from biomass in a formic acid-based cooking process, the process comprising the following steps:
• step (b) reacting the non-hydrolysed cellulose pulp from step (a") in a formic acid solution to produce levulinic acid and formic acid under the following conditions:
• the preparation step (b) of levulinic acid can be implemented in one or two steps in the manner described above.
• a levulinic acid solution can be recovered as a wash filtrate and used in the preparation of levulinic acid in step (b) to adjust the formic acid content to be suitable for the preparation of levulinic acid.
• a suitable formic acid content for the levulinic acid reactions is 20 to 60% of dry pulp.
• a formic acid solution can be recovered as a wash filtrate, from which formic acid is separated and returned to the cooking of step (a).
• step (a) in step (a") 30 to 70% of the cellulose is hydrolysed into glucose, and the non-hydrolysed cellulose is led to step (b) for the preparation of levulinic acid.
• the formic acid cooking of the cooking step (a) is performed by using cooking acid with a formic acid content in the range of 50 to 98%, preferably 70 to 98% (the rest is water).
• the cooking acid may also contain acetic acid, the amount being typically less than 30%, preferably less than 15%, particularly preferably less than 1 %, as calculated from the weight of the total cooking reagent.
• the amounts of formic acid and acetic acid are essentially equal.
• the cooking is performed at a temperature of 60 to 220°C, preferably 00 to 180°C, for example 130 to 170°C.
• peracid treatment can also be added to the cooking.
• the cellulose pulp obtained from the formic acid cooking which has been concentrated to a consistency of 10 to 40% and washed, is treated at 50 to 90°C with perform ic acid that is made by adding to the formic acid hydrogen peroxide at an amount of 0.5 to 3% of dry pulp, allowing the formic acid and hydrogen peroxide to react into performic acid during 1 to 10 minutes before the performic acid is added to the concentrated and washed pulp, and the performic acid treatment of the cellulose pulp is continued until the performic acid has essentially run out, and the treatment is continued thereafter by allowing the reaction mixture to react at the same temperature.
• Cooking produces cellulose pulp that is washed with formic acid.
• the formic acid used in washing may be the same in consistency and concentration as that used in cooking.
• Components dissolved from the cellulose pulp i.e. mainly lignin and hemicellulose, are removed in the acid wash.
• Cellulose pulp with a dry matter content of 20 to 30% is obtained, with the rest being a concentrated acid solution.
• Acids and lignin are separated from the wash filtrate. Acids are returned to cooking and/or acid wash.
• the acid solution used in cooking and washing is typically acid recovered from later steps of the process that has been returned to the process.
• the cellulose pulp obtained from step (a) is used in its entirety in the preparation of levulinic acid.
• part of the pulp is used in the preparation of levulinic acid and part in the preparation of a sugar product (glucose), bioethanol or alternatively dissolving pulp, for instance.
• the pulp used in the preparation of levulinic acid typically contains less than 10% of hemicellulose (as xylan).
• the process may also have after step (a) and before step (b) a step (aO), in which the cellulose pulp entering step (b) is washed with water or a formic acid solution (typical content 30 to 60%).
• a formic acid solution typically content 30 to 60%.
• the pulp is typically washed in steps and the amount of washing solution is adjusted so that a formic acid content of approximately 20 to 60% per dry pulp is obtained in the pulp. This has been found a suitable content for the following preparation reaction of levulinic acid.
• a formic acid-containing wash filtrate (content typically 30 to 60%) obtained from the water wash of the cellulose pulp of step (f) and intended for the preparation of bioethanol is used in the washing (aO).
• step (aO) the formic acid-content of the pulp is adjusted so that it is suitable for the preparation of levulinic acid.
• Step (aO) is advantageous when the cooking reagent contains only formic acid as the acid.
• step (aO) of the pulp is not needed, and the pulp can be led from step (a) acid wash directly to the preparation of levulinic acid.
• step (a') in an embodiment of the invention where a partial enzymatic hydrolysis into glucose is performed
• the cellulose pulp entering step (a") is washed with water and de-esterified to remove formic acid and other acids (acetic acid) formed during cooking or to reduce their amount to a suitable level for enzymatic hydrolysis.
• De-esterification is performed by treating the pulp with dilute formic acid (content 5 to 20%, preferably 10 to 15%) at low consistency (3 to 15%, preferably 5 to 10%) at a temperature of 70 to 90°C (preferably 85°C).
• the treatment time is 0.5 to 24 h, preferably 4 to 12 h.
• De-esterification takes place during the water washing of the pulp.
• organic acids which were bound to the pulp in a chemically esterified form in the cooking step are released from the cellulose pulp.
• the wash filtrate is used in the preparation step (b) of levulinic acid to adjust the formic acid content of the non-hydrolysed piilp to suit the preparation reactions of levulinic acid.
• a partial enzymatic hydrolysis is performed on the cellulose pulp obtained from step (a') for the production of glucose in step (a").
• the glucose (liquid hydrolysis product) obtained from the hydrolysis is separated from the hydrolysis residue (solid non-hydrolysed cellulose) and led to fermentation, for example the preparation of bioethanol, if desired.
• step (b) at least part of the cellulose pulp obtained in step (a) is allowed to react in a formic acid solution to produce levulinic acid and formic acid under the following conditions:
• the preparation of levulinic acid is performed in the presence of formic acid in the formic acid-content defined above, whereby the formic acid catalyses the formation of levulinic acid, and at the same time molecularly the same amount of formic acid is formed.
• the formic acid content of the reaction solution can be adjusted to the desired range in the manner described in step (aO) above, for example.
• the preparation of levulinic acid can be implemented in a one- or two-step process described above.
• the solid matter typically lignin-containing residue
• a solution containing levulinic acid and formic acid is obtained.
• Levulinic acid and formic acid as well as possibly other components are separated by distillation, for instance.
• the separated levulinic acid is recovered and sold as a commercial product. At least part of the formic acid formed in the levulinic acid reaction is returned as a make-up cooking chemical (a chemical replacing the formic acid loss) in the process, and the rest may be sold as a commercial product. This way, the process can be kept self-sufficient in terms of formic acid, and extra formic acid need not be acquired.
• the production of levulinic acid and formic acid can, if desired, be adjusted so that only the amount of formic acid is produced that is required as make-up chemical in the process (a molecularly equivalent amount of levulinic acid is obtained).
• the amount of formed levulinic acid can be calculated, when the required amount of formic acid per ton of cellulose and the total yield of cellulose or ethanol (in tons) are known.
• Molecularly the same amount of levulinic acid is then formed as the amount of make-up formic acid returned to the process. This provides an advantage in the economy of the total process.
• part of the cellulose pulp obtained in step (a) is used in the preparation of a sugar product (glucose) and, if desired, further in the preparation of bioethanol.
• the pulp is then first led to enzymatic hydrolysis to produce glucose and, if desired, on to fermentation to prepare bioethanol.
• the pulp may also be used in the preparation of dissolving pulp, for example.
• the biomass used as the starting material in the process is typically lignocellulosic material that may be any lignocellulosic plant material. It may be wood material, such as softwood or hardwood, such as eucalyptus or acacia. It may also be non-wood material based on herbaceous plants, bast fibres, leaf fibres or fruit seed fibres. Examples of usable materials based on herbaceous plants include straw, such as cereal straw (wheat, rye, oat, barley, rice), reeds, such as reed canary grass, common reed, papyrus, sugar cane, i.e.
• bagasse and bamboo, as well as grasses, such as esparto, sabai and lemon grass and sorghum.
• bast fibres include flax, such as stalks of common flax and stalks of oil flax, stalks of cassava, hemp, East Indian hemp, kenaf, jute, ramie, paper mulberry, gampi fibre and mitsumata fibre.
• leaf fibres include abaca and sisal.
• fruit seed fibres include cottonseed hairs and cotton linter fibres, kapok and coir fibre.
• Herbaceous plants growing in Finland and usable in the present invention include common reed, reed canary grass, timothy, cocksfoot, yellow sweet clover, smooth brome, red fescue, white sweet clover, red clover, goat's rue and alfalfa.
• biomass based on herbaceous plants such as cereal straw
• biomass based on annual herbaceous plants is used.
• biomass based on perennial non-wood plants is used.
• lignocellulose- containing waste material from industry or agriculture including empty fruit bunch of oil palm and the above-mentioned cereal straw, may also be used.
• the process of the invention may be included as part of a formic acid-based total process, in which bioethanol, levulinic acid and, if desired, other chemicals are produced from biomass and in which the formic acid formed in the preparation of levulinic acid is utilized as make-up chemical in biomass cooking.
• the biomass 1 is fed to cooking 120 together with cooking acid 21 ,32.
• Cooking acid 21 ,32 is an acid mixture originating from the formic acid recovered from the evaporation 190 of cooking acid and distillation 240 of levulinic acid.
• the cellulose pulp 7 obtained from cooking is led to acid washing 130, where the pulp is washed with the same acid mixture 21 ,32 as that used in cooking.
• the acid-containing wash filtrate from the acid wash is led to evaporation 190.
• the acid-washed cellulose pulp 8 is divided into two parts, of which one continues to water wash 140 and the other to water wash 210.
• the washed pulp 11 from water wash 140 is led on to enzymatic hydrolysis 150 and the thus obtained hydrolysis product (glucose) 14 is led to the preparation 160 of bioethanol.
• the second part continues to water wash 210.
• a filtrate 17 from water wash 140 is used, whereby the formic acid content of the pulp 18 obtained from water wash 140 is made suitable for the preparation 220 of levulinic acid.
• the preparation 220 of levulinic acid is performed formic acid-catalysed at an acid concentration adjusted with the wash filtrate 17.
• a stream 24 that contains levulinic acid and formic acid is obtained and led to separation, for instance filtration 230.
• Filtration 230 separates a lignin- containing residue 26 and a filtrate 27 containing levulinic acid and formic acid that is led to the distillery 240.
• acetic acid 28, furfural 29, levulinic acid 30, water 31 and formic acid-containing cooking acid 32 are separated. This is returned as make-up acid to cooking 120.
• the filtrate 19 from water wash 210 is led to evaporation 190, where the cooking acid 21 is separated and led back to biomass cooking 120.
• the concentrated cooking acid 20 obtained from evaporation 190 is led to the preparation 180 of furfural.
• the stream 22 obtained therefrom is led to lig- nin drying 200, from which lignin is obtained as a dry product 34, and a stream 33 containing furfural and acids is also obtained.
• the furfural and acid stream 33 is led to the distillery 240.
• the process of the invention may also be included as part of a formic acid-based total process, in which glucose, bioethanol, levulinic acid and, if desired, other chemicals are produced from biomass and in which the formic acid formed in the preparation of levulinic acid is utilized as make-up chemical in biomass cooking.
• the biomass 1 is fed to cooking 120 together with cooking acid 21 ,32.
• Cooking acid 21 ,32 is an acid mixture originating from the formic acid recovered from the evaporation 190 of cooking acid and distillation 240 of levulinic acid.
• the cellulose pulp 7 obtained from cooking is led to;ac- id washing 130, where the pulp is washed with the same acid mixture 21 ,32 as that used in cooking.
• the acid-containing wash filtrate from the acid wash is led to evaporation 190.
• the acid-washed cellulose pulp 8 continues to water wash and de-esterification 140.
• the obtained washed pulp 11 is led to enzymatic hydrolysis 150 performed with enzymes 13.
• the glucose is led to fermentation, for instance the preparation 160 of bioethanol.
• the solid cellulose is led to the preparation 220 of levulinic acid.
• the filtrate 17 from water wash 140 is used to adjust the formic acid content, whereby the formic acid content of the cellulose pulp 36 is made suitable for the preparation 220 of levulinic acid.
• the preparation 220 of levulinic acid is performed formic acid-catalysed at an acid concentration adjusted with the wash filtrate 17.
• a stream 24 that contains levulinic acid and formic acid is obtained and led to separation, for instance filtration 230.
• Filtration 230 separates a lignin- containing residue 26 and a filtrate 27 containing levulinic acid and formic acid that is led to the distillery 240.
• acetic acid 28, furfural 29, levulinic acid 30, water 31 and formic acid-containing cooking acid 32 are separated. This is returned as make-up acid to cooking 120.
• the filtrate 9 from acid wash 130 is led to evaporation 190, where the cooking acid 21 is separated and led back to biomass cooking 120.
• the concentrated cooking acid 20 obtained from evaporation 190 is led to the preparation 180 of furfural.
• the stream 22 obtained therefrom is led to lignin drying 200, from which lignin is obtained as a dry product 34, and a stream 33 containing furfural and acids is also obtained.
• the furfural and acid stream 33 is led to the distillery 240.
• Cellulose pulp was prepared by cooking wheat straw in 83% formic acid (cooking temperature approximately 140°C, liquid ratio approximately 5 and cooking time approximately 35 minutes).
• the formic acid used in cooking is typically acid regenerated from the total process supplemented by make-up formic acid obtained from the later levulinic acid preparation step. After this, the pulp was washed with approximately 82% formic acid in several steps.
• the formic acid used in washing pulp is also typically acid regenerated from the total process supplemented by formic acid obtained from the levulinic acid preparation step.
• the obtained pulp may be used in its entirety to prepare levulinic acid, or it may be divided into two parts, of which one is used in the preparation of bioethanol and the other in the preparation of levulinic acid.
• the pulp intended for the preparation of levulinic acid was washed with water (which may be a water wash filtrate of pulp intended for the preparation of bioethanol) so that the pulp contained approximately 20 to 30% of formic acid (calculated as percentage by weight of dry pulp).
• the acid- containing filtrate from the water wash is typically led to evaporation, where acid is separated and returned as cooking chemical to cooking.
• Ygiuc/puip, % by weight glucose yield from cellulose
• Ygiuc/puip, % by weight glucose yield from cellulose
• H F/P U IP, % by weight 5-hydroxy methyl furfural HMF (intermediate product) yield from cellulose
• Y /puip, % by weight levulinic acid yield from cellulose [0085] It was found that the first step mainly accelerated the degradation of cellulose into glucose and the second step accelerated the reaction of cellulose into 5-hydroxy methyl furfural (HMF) and on to levulinic acid and formic acid.
• HMF 5-hydroxy methyl furfural
• Example 2 hydrolysis of cellulose prepared from sweet sorghum bagasse
• Cellulose pulp was prepared by cooking sweet sorghum bagasse in 82% formic acid (cooking temperature 140°C and cooking time 12 minutes).
• the formic acid used in cooking is typically acid regenerated from the total process supplemented by make-up formic acid obtained from the later levulinic acid preparation step.
• peracid treatment with 1.9% per- acid was performed for 180 minutes. After this, the pulp was washed with the same 82% formic acid and then with water so that the acid content was reduced to be suitable for enzymatic hydrolysis.
• Cellulose pulp was prepared by cooking wheat straw in 82% formic acid (cooking temperature 138°C and cooking time 35 minutes).
• the formic acid used in cooking is typically acid regenerated from the total process supplemented by make-up formic acid obtained from a later levulinic acid preparation step.
• peracid treatment with 1.9% peracid was performed for 240 minutes. After this, the pulp was washed with the same 82% formic acid and then with water so that the acid content was reduced to be suitable for enzymatic hydrolysis.
• an enzyme dosage of 1.1 % (per dry cellulose) produces a hydrolysis degree of 37%, whereby the production of a glucose unit consumes 2.9% [1.1%/37%] of enzyme, and as calculated to a hydrolysis degree of 97%, 2.8% [1.1%/37%*97%] of enzyme.
• the difference (as calculated from dry cellulose) between a partial hydrolysis (37%) and a nearly complete hydrolysis (97%) is 4.1 % [5 2-1.1 %], and the difference has consumed 6.9% [4.1 %/(97%-37%)] of enzyme.
• the final hydrolysis consumes a nearly 2.5fold amount of enzyme per produced glucose unit in comparison with a partial hydrolysis.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Zoology (AREA)
• Wood Science & Technology (AREA)
• Biochemistry (AREA)
• Health & Medical Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Microbiology (AREA)
• General Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Biotechnology (AREA)
• Bioinformatics & Cheminformatics (AREA)
• General Engineering & Computer Science (AREA)
• Genetics & Genomics (AREA)
• Emergency Medicine (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Catalysts (AREA)
• Preparation Of Compounds By Using Micro-Organisms (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (1)

Family

ID=49160307

Family Applications (1)

Country Status (3)

Cited By (3)

Citations (4)

• 2012
  • 2012-07-23 FI FI20125815A patent/FI20125815A7/fi not_active Application Discontinuation
• 2013
  • 2013-03-13 WO PCT/FI2013/050281 patent/WO2013135965A1/en active Application Filing
  • 2013-03-13 IN IN1679MUN2014 patent/IN2014MN01679A/en unknown

Patent Citations (5)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events