Abstract: Digestion of cellulosic biomass solids can be enhanced in the presence of a phenolic solvent. Methods for digesting cellulosic biomass solids can comprise providing cellulosic biomass solids in a digestion medium comprising a phenolic solvent; and heating the cellulosic biomass solids and the digestion medium in a digestion unit in the presence of molecular hydrogen and a slurry catalyst capable of activating molecular hydrogen, thereby forming an alcoholic component derived from the cellulosic biomass solids and liberating lignin from the cellulosic biomass solids into the digestion medium. The methods can further comprise converting at least a portion of the lignin into a phenolic solvent and returning the phenolic solvent formed from lignin to the cellulosic biomass solids.

Abstract: Methods and systems for transferring feed materials between zones having substantially different pressures, where the transfer can be continuous or semi-continuous. The methods and systems include a plurality of lock hoppers to receive feed material from a low pressure zone and pressurize it with fluid to a pressure of a high pressure zone. The pressurized material can be discharged to a circulation loop, which carries the pressurized material to one or more receiving unit(s) of a pressurized system. At least some feed material remains in the receiving unit(s) and at least a portion of the fluid exits to become part of the circulation loop. After discharge, the lock hoppers can be depressurized so the next pressurization cycle can begin with additional feed material. The lock hoppers can be operated in a time-staggered manner to provide continuous or semi-continuous transfer of material.

Abstract: Digestion of cellulosic biomass solids may be complicated by release of lignin therefrom. Methods and systems for processing a reaction product containing lignin-derived products, such as phenolics, can comprise hydrotreating the reaction product to convert the lignin-derived products to desired higher molecular weight compounds. The methods can further include separating the higher molecular weight compounds from unconverted products, such as unconverted phenolics, and recycling the unconverted phenolics for use as at least a portion of the digestion solvent and for further conversion to desired higher molecular weight compounds with additional hydrotreatment. The methods and systems can further include generating hydrogen with the further hydrotreatment.

Abstract: Digestion of cellulosic biomass solids may be complicated by release of lignin therefrom. Methods and systems for processing a reaction product containing lignin-derived products, such as phenolics, can comprise hydrotreating the reaction product to convert the lignin-derived products to desired higher molecular weight compounds. The methods can further include separating the higher molecular weight compounds from unconverted products, such as unconverted phenolics, and recycling the unconverted phenolics for use as at least a portion of the digestion solvent and for further conversion to desired higher molecular weight compounds with additional hydrotreatment.

Abstract: Digestion of cellulosic biomass solids may be complicated by release of lignin therefrom. Methods and systems for processing a reaction product containing lignin-derived products, such as phenolics, can comprise hydrotreating the reaction product to convert the lignin-derived products to desired higher molecular weight compounds. The methods and systems can further include separating the higher molecular weight compounds from unconverted products, such as unconverted phenolics, and recycling the unconverted phenolics for use as at least a portion of the digestion solvent and for further conversion to desired higher molecular weight compounds with additional hydrotreatment. The methods and systems can further include a further hydrotreatment step configured for additional lignin conversion and/or a further hydrotreatment step configured for generating hydrogen.

Abstract: A method comprises providing a bio-based feedstock; contacting the bio-based feedstock with a solvent in a hydrolysis reaction to form an intermediate stream comprising carbohydrates; contacting the intermediate stream with an apr catalyst to form a plurality of oxygenated intermediates, wherein a first portion of the oxygenated intermediates are recycled to form the solvent; and processing at least a second portion of the oxygenated intermediates to form a fuel blend.

Abstract: Digestion of cellulosic biomass solids may be complicated by release of lignin therefrom. Methods for digesting cellulosic biomass solids may comprise: providing cellulosic biomass solids in a digestion solvent; at least partially converting the cellulosic biomass solids into a phenolics liquid phase comprising lignin, an aqueous phase comprising an alcoholic component derived from the cellulosic biomass solids, and an optional light organics phase; combining at least the phenolics liquid phase and the aqueous phase with one another, thereby forming a combined phase; and separating at least a portion of the alcoholic component from at least a portion of the combined phase.

Abstract: A method comprises introducing cellulosic biomass solids to a digester comprising a reactor, gas feed line, biomass feed system, fluid circulation system including a fluid inlet, a pump, and an injector, a screen positioned within the reactor and defining a lower zone therebelow, and a bed of reactor packing material resting on the screen and defining thereby a packed zone; providing a liquid phase digestion medium containing a slurry catalyst in the digester, the catalyst being capable of activating molecular hydrogen; circulating the liquid phase digestion medium through the fluid circulation system; supplying an upwardly directed flow of molecular hydrogen through the cellulosic biomass solids; and maintaining the cellulosic biomass solids and slurry catalyst at a temperature sufficient to cause digestion of cellulosic biomass solids into an alcoholic component.

Abstract: Biomass compaction during hydrothermal digestion of cellulosic biomass solids may become problematic, particularly as the vertical height of a cellulosic biomass charge increases. Compaction may be decreased in a horizontally configured hydrothermal digestion unit.

Abstract: Maintaining long residence times during hydrothermal digestion of cellulosic biomass solids may be complicated by a number of factors, including biomass compaction. Advantages in this regard may be realized by digesting cellulosic biomass solids in an inclined digestion unit. Such methods can comprise: introducing cellulosic biomass solids to a hydrothermal digestion unit comprising one or more inclined surfaces therein; introducing a fluid phase digestion medium containing a slurry catalyst to the hydrothermal digestion unit, the slurry catalyst being capable of activating molecular hydrogen; supplying an upwardly directed flow of molecular hydrogen from a source disposed along each inclined surface as the cellulosic biomass solids descend along each inclined surface; and heating the cellulosic biomass solids as they descend along each inclined surface in the presence of the slurry catalyst and the molecular hydrogen, thereby forming an alcoholic component derived from the cellulosic biomass solids.

Abstract: Biofuels can be produced by: (i) providing a biomass containing celluloses, hemicelluloses, lignin, nitrogen compounds and sulfur compounds; (ii) removing sulfur compounds and nitrogen compounds from the biomass by contacting the biomass with a digestive solvent to form a pretreated biomass containing carbohydrates and having less than 35% of the sulfur content and less than 35% of the nitrogen content of untreated biomass on a dry mass basis; (iii) contacting the pretreated biomass directly with hydrogen in the presence of a hydrogenolysis catalyst to form a plurality of oxygenated intermediates, and (vi) processing at least a portion of the oxygenated intermediates to form a liquid fuel.

Abstract: Methods and systems for co-producing higher hydrocarbons and glycols from bio-based feedstocks containing carbohydrates are disclosed.

Abstract: Digestion units for processing cellulosic biomass can comprise a chamber having a height that is greater than its width, the chamber having an opening suitable for solids introduction located within the upper 20% of its height; one or more first fluid conduits connected to the chamber within the lower 20% of its height, at least one of the first fluid conduits extending into the chamber and being elevated above the bottom of the chamber; one or more second fluid conduits connected to the chamber within the upper 20% of its height, at least one of the first fluid conduits being fluidly coupled to at least one of the second fluid conduits; a porous medium located in the chamber within the lower 20% of its height; and a movable pressure isolation device covering the opening; wherein the digestion unit is operable to maintain a pressure of at least about 30 bar.

Abstract: Methods and systems for co-producing higher hydrocarbons and glycols from bio-based feedstocks containing carbohydrates are disclosed.

Abstract: Hydrothermal digestion of cellulosic biomass solids may produce a glycol reaction product for subsequent processing.

Abstract: Digesting cellulosic biomass in the presence of a slurry catalyst may reduce degradation product formation, but catalyst distribution and retention can be problematic. Digestion methods can comprise: providing cellulosic biomass solids and a slurry catalyst capable of activating molecular hydrogen in a digestion unit; providing a digestible filter aid in the digestion unit; distributing the slurry catalyst within the cellulosic biomass solids using fluid flow; retaining at least a portion of the slurry catalyst in a fixed location using the digestible filter aid; heating the cellulosic biomass solids in the presence of the slurry catalyst, a digestion solvent, and molecular hydrogen, thereby forming a liquor phase comprising soluble carbohydrates; and performing a catalytic reduction reaction on the soluble carbohydrates within the digestion unit, thereby at least partially forming a reaction product comprising a triol, a diol, a monohydric alcohol, or any combination thereof in the digestion unit.

Abstract: When processing cellulosic biomass, it may be desirable for a digestion unit to operate without being fully depressurized for process efficiency purposes. A biomass conversion system can comprise a first digestion unit and a second digestion unit that are operatively connected to one another; a valve separating the first digestion unit from the second digestion unit; a fluid circulation loop establishing fluid communication between an outlet of the first digestion unit and an inlet of the second digestion unit; and a bypass line establishing fluid communication between an outlet of the second digestion unit and the fluid circulation loop.

Abstract: Hydrothermal digestion of cellulosic biomass solids in a glycerol solvent system can convert both the cellulosic biomass solids and the glycerol into a glycol reaction product for subsequent processing without the need for further solvent separation. Methods for digesting cellulosic biomass solids in a glycerol solvent system can comprise: providing cellulosic biomass solids and a slurry catalyst in a hydrothermal digestion unit, the slurry catalyst being capable of activating molecular hydrogen; heating the cellulosic biomass solids in the hydrothermal digestion unit in the presence of the slurry catalyst, molecular hydrogen, and a solvent system comprising glycerol, thereby forming soluble carbohydrates; and at least partially converting the soluble carbohydrates and the glycerol into a reaction product comprising a glycol within the hydrothermal digestion unit.

Abstract: Biomass is contacted with an aqueous media to form an extracted biomass. An aqueous liquor separated from the extracted biomass is treated with a purification substrate to form a treated carbohydrate stream having less than 35% of the sulfur content and less than 35% of the nitrogen content, based on the untreated aqueous liquor stream, prior to contact with an aqueous phase reforming catalyst to form oxygenated intermediates that can be further processed to form a liquid fuel. An extracted biomass solids stream is also separated from the extracted biomass which is contacted with a first digestive solvent and then a second digestive solvent to form a solubilized pulp. This solublilized pulp may be combined with the aqueous liquor stream or combined to an aqueous reforming reaction system or recycled to the aqueous media to be processed further for an effective process to produce the liquid fuel.

Abstract: A method of hydrothermal hydrocatalytic treating biomass is provided. Lignocellulosic biomass solids is provided to a hydrothermal digestion unit in the presence of a digestive solvent, and a supported hydrogenolysis catalyst containing (a) sulfur, (b) Mo or W, and (c) Co, Ni or mixture thereof, incorporated into a group 4 metal oxide support; (ii) heating the lignocellulosic biomass solids and digestive solvent in the presence of hydrogen, and the supported hydrogenolysis catalyst thereby forming a product solution containing plurality of oxygenated hydrocarbons, said catalyst retaining a crush strength of at least 50% after being subjected to an aqueous phase stability test compared with before the aqueous phase stability test or a crush strength of at least 0.25 kg after being subjected to an aqueous phase stability test.