Abstract: Exemplary compositions comprise at least one aldopentonic acid, such as xylonic acid; and further comprise a lignin, a lignosulfonic acid or its salt, an additional sugar acid such as a aldohexonic acid or salt, a conventional admixture (such as a polyacrylate superplasticizer, a corrosion inhibitor, a set retard, a set accelerator, etc.), or a mixture thereof. Exemplary methods for obtaining microbiologically or enzymatically converted sugar acids are also described herein.

Abstract: A biodegradable sugar-inorganic hybrid composite comprising a sugar or a sugar derivative uniformly dispersed in a matrix of an inorganic oxide, of which degradation products are suitable for recycling use.

Abstract: The present invention provides a method of producing xylose from lignocellulosic feedstock. The method comprises disrupting lignocellulosic feedstock; leaching the lignocellulosic feedstock by contacting the feedstock with at least one aqueous solution for a period greater than about 2 minutes to produce a leached feedstock and a leachate; removing the leachate from the leached feedstock; acidifying the leached feedstock to a pH between about 0.5 and about 3 to produce an acidified feedstock, and; reacting the acidified feedstock under conditions which disrupt fiber structure and hydrolyze a portion of hemicellulose and cellulose of the acidified feedstock, to produce a composition comprising xylose and a pretreated feedstock. The xylose may be purified from the pretreated feedstock or it may be converted to ethanol with the pretreated feedstock.

Abstract: A method for selective hydrolysis of the hemicellulose component of a biomass material. The selective hydrolysis produces water-soluble small molecules, particularly monosaccharides. One embodiment includes solubilizing at least a portion of the hemicellulose and subsequently hydrolyzing the solubilized hemicellulose to produce at least one monosaccharide. A second embodiment includes solubilizing at least a portion of the hemicellulose and subsequently enzymatically hydrolyzing the solubilized hemicellulose to produce at least one monosaccharide. A third embodiment includes solubilizing at least a portion of the hemicellulose by heating the biomass material to greater than 110° C. resulting in an aqueous portion that includes the solubilized hemicellulose and a water insoluble solids portion and subsequently separating the aqueous portion from the water insoluble solids portion.

Abstract: A process of converting lignocellulosic biomass to ethanol, comprising hydrolyzing lignocellulosic materials by subjecting dried lignocellulosic material in a reactor to a catalyst comprised of a dilute solution of a strong acid and a metal salt to lower the activation energy (i.e., the temperature) of cellulose hydrolysis and ultimately obtain higher sugar yields.

Abstract: A process is described for the production of decomposable soluble products from a slurry of solids in which the slurry is convey axially through the reactor and excess liquid is removed radially through the walls of the reactor. The primary example is the hydrolysis of lignocellulosic biomass to form sugars, usually using an acid catalyst. In one variation of the process liquid and possibly steam are added through the inner wall of the reactor to provide additional flow in the radial direction and to control the temperature. Pressures are maintained such that the product stream is thermally quenched due to partial flashing as it leaves the reactor.

Abstract: Exemplary compositions comprise at least one aldopentonic acid, such as xylonic acid; and further comprise a lignin, a lignosulfonic acid or its salt, an additional sugar acid such as a aldohexonic acid or salt, a conventional admixture (such as a polyacrylate superplasticizer, a corrosion inhibitor, a set retard, a set accelerator, etc.), or a mixture thereof. Exemplary methods for obtaining microbiologically or enzymatically converted sugar acids are also described herein.

Abstract: A multi-function process is described for the separation of cellulose fibers from the other constituents of lignocellulosic biomass such as found in trees, grasses, agricultural waste, and waste paper with application in the preparation of feedstocks for use in the manufacture of paper, plastics, ethanol, and other chemicals. This process minimizes waste disposal problems since it uses only steam, water, and oxygen at elevated temperature in the range of 180° C. to 240° C. for 1 to 10 minutes plus a small amount of chemical reagents to maintain pH in the range 8 to 13. An energy recuperation function is important to the economic viability of the process.

Abstract: By providing a biomass and an aqueous acidic solution to a hydrolysis vessel, hydrolysis within the hydrolysis vessel, forms sugars. The aqueous acidic solution, containing sugars, is withdrawn from the hydrolysis vessel and transferred to a phase forming vessel to form two phases; a sugar phase and an aqueous acidic solution phase. The sugar phase, upon withdrawing from the phase forming vessel, is subjected to additional processing outside the hydrolysis vessel. Residue, containing lignins remaining from the biomass, is withdrawn from the hydrolysis vessel and subjected to filtration resulting in a filtrate for recycle to the hydrolysis vessel and ffiltered residue for subsequent processing. Thereby, sugars are derived from a biomass, and residue, remaining from the biomass, is withdrawn from the hydrolysis vessel.

Abstract: A process for enzymatic treatment comprising an enzyme reaction to obtain an enzyme reaction product by allowing an enzyme to act on a substrate, wherein the enzyme reaction is performed under pressure.

Abstract: The invention relates to a process for the production of xylose from a paper-grade hardwood pulp comprising the steps of extracting xylan contained in said pulp into a liquid phase, subjecting the xylan contained in the obtained liquid phase to conditions sufficient to hydrolyze xylan to xylose, and recovering the xylose, wherein the extracting step includes at least one treatment of an aqueous suspension of said pulp or an alkali-soluble material thereof with a xylanase enzyme.

Abstract: The invention relates to a method of simultaneous purification and separation of pectin and pectic sugars/oligomers from sugar beet pulp using a multi-step process in an aqueous solution. The method comprises hydrolysis of the sugar beet pulp, solids separation from the sugar beet pulp hydrolysate as well as fractionation and desalting of the aqueous solution of the sugar beet pulp hydrolysate thus obtained into a desalted solution enriched in pectin and a desalted solution enriched in pectic sugars/oligomers. The process may also comprise optional further steps, such as clarification, adsorption, concentration and further chromatographic treatment.

Abstract: A modified dilute acid method of hydrolyzing the cellulose and hemicellulose in lignocellulosic material under conditions to obtain higher overall fermentable sugar yields than is obtainable using dilute acid alone, comprising: impregnating a lignocellulosic feedstock with a mixture of an amount of aqueous solution of a dilute acid catalyst and a metal salt catalyst sufficient to provide higher overall fermentable sugar yields than is obtainable when hydrolyzing with dilute acid alone; loading the impregnated lignocellulosic feedstock into a reactor and heating for a sufficient period of time to hydrolyze substantially all of the hemicellulose and greater than 45% of the cellulose to water soluble sugars; and recovering the water soluble sugars.

Abstract: A method for separating acid and sugars obtained from liquids resulting from the acid hydrolysis of a material containing at least one of cellulose and hemicellulose is disclosed, comprising adding the liquids to a separation unit comprising a bed of anionic exchange or exclusion chromatographic material whereby the acid is adsorbed onto the chromatographic material, thereby producing a series of first fractions comprising sugar solutions and a later series of fractions comprising acid solutions. A process for an economical, energy efficient production of ethanol from municipal solid waste and other cellulosic feedstocks is also disclosed.

Abstract: A multi-function process is described for the separation of cellulose fibers from the other constituents of lignocellulosic biomass such as found in trees, grasses, agricultural waste, and waste paper with application in the preparation of feedstocks for use in the manufacture of paper, plastics, ethanol, and other chemicals. This process minimizes waste disposal problems since it uses only steam, water, and oxygen at elevated temperature in the range of 180° C. to 240° C. for 1 to 10 minutes plus a small amount of chemical reagents to maintain pH in the range 8 to 13. An energy recuperation function is important to the economic viability of the process.

Abstract: Disclosed are processes and systems for the production of useful organic product from diverse lignocellulose-containing biomass having increased yield and efficiency over existing processes. In particular, the present invention integrates dilute acid hydrolysis and alkaline delignification techniques in processes that enhance the efficiency and yiel of lignocellulostic biomass processing and enable the economic production lignin-based biodegradable plastics and other useful organic products.

Abstract: A method for separating acid and sugars obtained from liquids resulting from the acid hydrolysis of a material containing at least one of cellulose and hemicellulose is disclosed, comprising adding the liquids to a separation unit comprising a bed of anionic exchange or exclusion chromatographic material whereby the acid is adsorbed onto the chromatographic material, thereby producing a series of first fractions comprising sugar solutions and a later series of fractions comprising acid solutions. A process for an economical, energy efficient production of ethanol from municipal solid waste and other cellulosic feedstocks is also disclosed.

Abstract: There is disclosed a process for production of water-soluble vegetable fibers in a high yield with minimizing contamination of protein or amino acids resulting from degradation of protein by degrading water-insoluble vegetable fibers containing protein under acidic conditions of at about the isoelectric point of the protein and at a temperature of 130° C. or lower. Biodegradable films, paste, chewing gum and low calorie food products using the water-soluble vegetable fibers are also disclosed.

Abstract: A method is presented that will produce fermentable sugars from a lignocellulose material employing concentrated sulfuric acid to dissolve cellulose and hemicellulose in a lignocellulose material followed by hydrolysis in place to depolymerize the cellulose and hemicellulose to produce fermentable sugars and separated water insoluble solids. The concentrated sulfuric acid, containing sugars and water insoluble solids, is then combined with ethanol from a previous extraction, containing ethanol, to precipitate the sugars and is co-mingled with the water insoluble solids to form solids and a solution of ethanol and sulfuric acid. The solution of ethanol and sulfuric acid containing solids is then separated to produce solids and a solution containing ethanol and sulfuric acid. The separated solids are extracted with ethanol and will substantially extract residual sulfuric acid from the separated solids creating ethanol extracted solids and provide an extractate to precipitate additional sugars.

Abstract: This process involves feeding cellulose into an extruder with an acid solution. The extruder is comprised of a screw and a barrel. The screw is rotated so as to pressurize the cellulose, and the cellulose undergoes acid hydrolysis and forms microcrystalline cellulose. The invented process can be accomplished by using pure cellulose or a lignocellulosic material as the starting material. If a lignocellulosic material is used, then a basic solution is added to it and the lignocellulosic material is fed through an extruder so as to obtain a mixture comprising lignin, hemicellulose and cellulose. The lignin and hemicellulose are extracted and the remaining cellulose is processed, as discussed previously, to form microcrystalline cellulose.

Abstract: A multi-function process for hydrolysis and fractionation of lignocellulosic biomass to separate hemicellulosic sugars from other biomass components comprising extractives and proteins; a portion of a solubilized lignin; cellulose; glucose derived from cellulose; and insoluble lignin from said biomass comprising: a) introducing either solid fresh biomass or partially fractioned lignocellulosic biomass material with entrained acid or water into a reactor and heating to a temperature of up to about 185° C.-205° C. b) allowing the reaction to proceed to a point where about 60% of the hemicellulose has been hydrolyzed in the case of water or complete dissolution in case of acid; c) adding a dilute acid liquid at a pH below about 5 at a temperature of up to about 205° C. for a period ranging from about 5 to about 10 minutes; to hydrolyze the remaining 40% of hemicellulose if water is used. d) quenching the reaction at a temperature of up to about 140° C.

Abstract: A method of creating a number of separate product streams from an agricultural waste material, comprising: providing a starting material consisting of an agricultural waste material; hydrolyzing the starting material with an acid solution at atmospheric pressure, and temperatures not exceeding about 100.degree. C., to create an absorbent, hydrolyzed solid residue and a xylose-containing liquor; reserving the xylose-containing liquor; and delignifying the hydrolyzed solid residue with a basic solution, to create a fiber solid residue suitable for use as an absorbent material, and a dissolved lignin-containing solution.

Abstract: An improved pretreatment of cellulosic feedstocks, to enable economical ethanol production by enzyme treatment. The improved pretreatment comprises choosing either a feedstock with a ratio of arabinoxylan to total nonstarch polysaccharides (AX/NSP) of greater than about 0.39, or a selectively bred feedstock on the basis of an increased ratio of AX/NSP over a starting feedstock material, and reacting at conditions that disrupt the fiber structure and hydrolyze a portion of the cellulose and hemicellulose. This pretreatment produces a superior substrate for enzymatic hydrolysis, by enabling the production of more glucose with less cellulose enzyme than any known procedures. This pretreatment is uniquely suited to ethanol production. Preferred feedstocks with an AX/NSP level greater than about 0.39 include varieties of oat hulls and corn cobs.

Abstract: The invention relates to a method for the recovery of xylose from xylose-containing aqueous solutions containing 30-60% by weight of xylose on dissolved solids, in which method the solution is treated to produce a solution supersaturated with xylose, xylose is crystallized from the supersaturated solution and the xylose crystals are recovered.

Abstract: A multi-function process is described for the hydrolysis and fractionation of lignocellulosic biomass to separate hemicellulosic sugars from other biomass components such as extractives and proteins; a portion of the solubilized lignin; cellulose; glucose derived from cellulose; and insoluble lignin from said biomass comprising one or more of the following: optionally, as function 1, introducing a dilute acid of pH 1.0-5.0 into a continual shrinking bed reactor containing a lignocellulosic biomass material at a temperature of about 94 to about 160.degree. C. for a period of about 10 to about 120 minutes at a volumetric flow rate of about 1 to about 5 reactor volumes to effect solubilization of extractives, lignin, and protein by keeping the solid to liquid ratio constant throughout the solubilization process; as function 2, introducing a dilute acid of pH 1.0-5.

Abstract: A method to recycle aqueous acidic liquor used to form depolymerized cellulose and hemicellulose accompanying cellulose, contained in biomass, by hydrolysis in the aqueous acidic liquor. Cellulose is dissolved in the aqueous acidic liquor and then remains in place to hydrolyze cellulose to form depolymerized cellulose in the aqueous acidic liquor. The depolymerized cellulose, including dextrins, oligosaccharides, and glucose is substantially separated from the aqueous acidic liquor. The separated aqueous acidic liquor is then recycled to dissolve and hydrolyze additional cellulose to form additional depolymerized cellulose.

Abstract: There is disclosed a process for production of water-soluble vegetable fibers in a high yield with minimizing contamination of protein or amino acids resulting from degradation of protein by degrading water-insoluble vegetable fibers containing protein under acidic conditions of at about the isoelectric point of the protein and at a temperature of 130.degree. C. or lower. Biodegradable films, paste, chewing gum and low calorie food products using the water-soluble vegetable fibers are also disclosed.

Abstract: Dilute solutions of fermentation sales may be concentrated by extracting water using low-miscibility, low-molecular-weight secondary and tertiary amines, e.g. triethylamine (TEA), diisopropyl amine (DIA), N,N-diethylmethylamine (DEMA), and mixtures thereof. At 30.degree. C.-55.degree. C., which corresponds to typical fermentation temperatures, these low-molecular-weight amines or their mixtures, can extract large amounts of water from dilute aqueous solutions containing fermentation salts. Thus, dilute fermentation salt solutions can be concentrated by selectively removing water. At these low temperatures, the amine phase contains 20-35% water and a much reduced quantity of fermentation salt. When the temperature is raised, water phases out of the amine, allowing the amine to be recycled and reused to extract additional water. Using this approach, about 82.

Abstract: A process, system, and apparatus for effectively and economically producing fermentable sugars from cellulosic feedstocks is described. The economic viability of using wood and/or agricultural waste, containing large fractions of cellulose and hemicellulose is highly dependent on the method used for hydrolysis. Underlying the gist of this invention are newly discovered methods, means, and techniques by which both the pentosans and hexosans comprising the hemicellulose fraction of the selected feedstock and the hexosans comprising the cellulose fraction of the selected feedstock can be quickly and efficiently converted in a single pass through a single device to fermentable sugars containing minimal quantities of degradation products known to inhibit fermentation.

Abstract: A method for separating acid and sugars obtained from liquids resulting from the acid hydrolysis of a material containing at least one of cellulose and hemicellulose is disclosed, comprising adding the liquids to a separation unit comprising a bed of anionic exchange or exclusion chromatographic material whereby the acid is adsorbed onto the chromatographic material, thereby producing a series of first fractions comprising sugar solutions and a later series of fractions comprising acid solutions. A process for an economical, energy efficient production of ethanol from municipal solid waste and other cellulosic feedstocks is also disclosed.

Abstract: An improved pretreatment of cellulosic feedstocks, to enable economical ethanol production by enzyme treatment. The improved pretreatment comprises choosing either a feedstock with a ratio of arabinoxylan to total nonstarch polysaccharides (AX/NSP) of greater than about 0.39, or a selectively bred feedstock on the basis of an increased ratio of AX/NSP over a starting feedstock material, and reacting at conditions that disrupt the fiber structure and hydrolyze a portion of the cellulose and hemicellulose. This pretreatment produces a superior substrate for enzymatic hydrolysis, by enabling the production of more glucose with less cellulase enzyme than any known procedures. This pretreatment is uniquely suited to ethanol production. Preferred feedstocks with an AX/NSP level greater than about 0.39 include varieties of oat hulls and corn cobs.

Abstract: Hydrolyzing organic waste material in a multi-stage reactor comprising a heated first stage, a further heated second stage, a still further heated third stage, and a fourth stage, with a valved exit way connected to the fourth stage and a valve entryway connected to the first stage.

Abstract: The present invention relates to a continuous process for acid hydrolysis of lignocellulosic material through which the delignification and saccharification operations are carried out in a single reaction cycle utilizing a solubilizing organic solvent of lignin and a strong and extremely diluted inorganic acid, and obtaining highly concentrated recoveries of sugar. For the execution of the present process a hydrolysis reactor is further presented.

Abstract: Glucose is obtained from papermaking sludge by first removing calcium carbonate from the sludge to produce a mixture substantially depleted of calcium and containing cellulose; and then hydrolyzing the calcium-depleted mixture using either a dilute or a strong acid. The glucose, as well as calcium salts removed from the sludge, may be isolated and used in numerous applications.

Abstract: The invention is directed to methods for the pretreatment of a lignocellulose-containing biomass. Pretreatment comprises the addition of calcium hydroxide and water to the biomass to form a mixture, and subjecting the mixture to relatively high temperatures for a period of time sufficient to render the biomass amenable to digestion. The pretreated biomass is digested to produce useful products such as feedstocks, fuels, and compounds including fatty acids, sugars, ketones and alcohols. Alternatively, the pretreatment process includes the addition of an oxidizing agent, selected from the group consisting of oxygen and oxygen-containing gasses, to the mixture under pressure. The invention is also directed to a method for the recovery of calcium from the pretreated biomass.

Abstract: A pulp of milled agave plant heads are liquified during centrifugation and a polyfructose solution is removed and then concentrated to produce a polyfructose concentrate. Small particulates are removed by centrifugation and/or filtration and colloids are removed using termic coagulation techniques to produce a partially purified polyfructose extract substantially free of suspended solids. The polyfructose extract is treated with activated charcoal and cationic and anionic resins to produce a demineralized, partially hydrolyzed polyfructose extract. This partially hydrolyzed polyfructose extract is then hydrolyzed with inulin enzymes to produce a hydrolyzed fructose extract. Concentration of the fructose extract yields a fructose syrup.

Abstract: A economically viable method for producing sugars using concentrated acid hydrolysis of biomass containing cellulose and hemicellulose is disclosed. The cellulose and hemicellulose in the biomass is first decrystallized and then hydrolyzed to produce a hydrolysate containing both sugars and acid. Silica present in the biomass can then be removed for further processing. The remaining solids are then subjected to a second decrystallization and hydrolyzation to optimize the sugar yields. An improved method for separating the sugars from the acid in the hydrolysate is also disclosed. The resulting sugar stream can then be fermented, using an improved method which allows both hexose and pentose sugars to be fermented simultaneously.

Abstract: A method of removing silica or silicates from solids results from the acid hydrolysis of materials containing cellulose and hemicellulose is disclosed. The method includes the steps of treating the solids with a metal hydroxide solution to produce an extract, reducing the pH of the extract to produce silicic acid, and removing the silicic acid from the extract.

Abstract: An Alcaligenes bacterium has been isolated from municipal sewage that contains a chitin deacetylase that can deacetylate chitin to chitosan.

Abstract: A method for separating lignocellulosic material into (a) lignin, (b) cellulose, and (c) hemicellulose and dissolved sugars. Wood or herbaceous biomass is digested at elevated temperature in a single-phase mixture of alcohol, water and a water-immiscible organic solvent (e.g., a ketone). After digestion, the amount of water or organic solvent is adjusted so that there is phase separation. The lignin is present in the organic solvent, the cellulose is present in a solid pulp phase, and the aqueous phase includes hemicellulose and any dissolved sugars.

Abstract: A economically viable method for producing sugars using concentrated acid hydrolysis of biomass containing cellulose and hemicellulose is disclosed. The cellulose and hemicellulose in the biomass is first decrystallized and then hydrolyzed to produce a hydrolysate containing both sugars and acid. Silica and silicates present in the biomass can then be removed for further processing. The remaining solids are then subjected to a second decrystallization if necessary and a second hydrolyzation to optimize the sugar yields.

Abstract: Cellulosic material is converted to ethanol by hydrolyzing the cellulosic material in a gravity pressure vessel (50), and fermenting the product thereof. The gravity pressure vessel (50) employed is adapted to accommodate a continuous hydrolysis reaction and maximize the fermentable product yield on a commercial scale. The gravity pressure vessel (50) employed is also adapted to maximize the thermodynamic efficiencies of the hydrolysis reaction, as well as the entire ethanol producing process.

Abstract: The invention relates to the prehydrolysis of lignocellulose by passing an acidic or alkaline solution through solid lignocellulosic particles with removal of soluble components as they are formed. The technique permits a less severe combination of pH, temperature and time than conventional prehydrolysis. Furthermore, greater extraction of both hemicellulose and lignin occurs simultaneously in the same reactor and under the same conditions.

Abstract: A woody or non-woody biomass is delignified through continuous extrusion technology, utilizing high-pressure steam to break down complex biomass materials. The process is useful to form a hydrophobic fiber material for use as an extrusion filler, a plastics modifier, and in the papermaking arts. Alternatively, the process is useful for preparing dietary feeds for ruminant animals, as well as to produce a broad range of alcohols or polymers from lignocellulosic substrates.

Abstract: Lignocellulose-containing materials are treated with lime (calcium hydroxide) and water at a relatively high temperature and for a certain period of time under certain conditions. The process variables were: lime loading which ranged from about 2 to about g Ca(OH).sub.2 /100 g dry material; water loading which ranged from about 6 to about 19 g water/g dry material; treatment temperature which varied from about 50.degree. C. to about 150.degree. C.; and treatment time which varied from about 1 to about 36 hours. The effects of treatment time and temperature were interdependent.A process for lime recovery is developed. The soluble Ca(OH).sub.2 was washed out of the pretreated material with water and converted to insoluble CaCO.sub.3, by reacting with CO.sub.2, and was thus separated. The CaCO.sub.3 can be heated to produce CaO and CO.sub.2. The CaO is hydrated to Ca(OH).sub.2 which can be reused as the lignocellulose treatment agent. Carbon dioxide is reused for lime recovery.

Abstract: A method of producing sugars and converting the sugars to ethanol in which particulate biomass resulting from hydrolysis of the hemicellulosic content of the biomass is subjected to enzymatic hydrolysis of the cellulosic content to glucose and fermentation of the glucose to ethanol. The particulate biomass resulting from hydrolysis of the hemicellulosic content of the feed stock is reduced to very fine particle size before enzymatic hydrolysis. The hydrolysis of cellulose and the fermentation of the resulting glucose may be carried out separately or they may be carried out simultaneously. The pentoses and hexoses resulting from hydrolysis of the hemicellulose may be subjected to fermentation separately to produce ethanol or they may be fermented simultaneously with the fermentation of the glucose derived from the cellulose.

Abstract: An economically viable method of fermenting a mixture of sugars resulting from the acid hydrolysis of material containing cellulose and hemicellulose allows for the simultaneous fermentation of both pentose and hexose sugars. The sugar solution is mixed with a microbial organism known to produce a useful fermentation product, and the fermentation process is allowed to proceed for 3-5 days, during and after which the fermentation products are removed and purified.

Abstract: A economically viable method for producing sugars using concentrated acid hydrolysis of biomass containing cellulose and hemicellulose is disclosed. The cellulose and hemicellulose in the biomass is first decrystallized and then hydrolyzed to produce a hydrolysate containing both sugars and acid. Silica and silicates present in the biomass can then be removed for further processing. The remaining solids are then subjected to a second decrystallization if necessary and a second hydrolyzation to optimize the sugar yields.

Abstract: There is disclosed a process for production of water-soluble vegetable fibers in a high yield with minimizing contamination of protein or amino acids resulting from degradation of protein by degrading water-insoluble vegetable fibers containing protein under acidic conditions of at about the isoelectric point of the protein and at a temperature of 130.degree. C. or lower. Biodegradable films, paste, chewing gum and low calorie food products using the water-soluble vegetable fibers are also disclosed.

Abstract: A economically viable method for producing sugars using concentrated acid hydrolysis of biomass containing cellulose and hemicellulose is disclosed. The cellulose and hemicellulose in the biomass is first decrystallized and then hydrolyzed to produce a hydrolysate containing both sugars and acid. Silica present in the biomass can then be removed for further processing. The remaining solids are then subjected to a second decrystallization and hydrolyzation to optimize the sugar yields. An improved method for separating the sugars from the acid in the hydrolysate is also disclosed. The resulting sugar stream can then be fermented, using an improved method which allows both hexose and pentose sugars to be fermented simultaneously.