摘要:
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.
摘要:
When processing cellulosic biomass, it may be desirable for a digestion unit to operate without being fully depressurized for process efficiency purposes. Methods for processing cellulosic biomass may comprise providing a biomass conversion system comprising a pressurization zone and a digestion unit that are operatively connected to one another; providing cellulosic biomass at a first pressure; introducing at least a portion of the cellulosic biomass into the pressurization zone and pressurizing the pressurization zone to a second pressure higher than the first pressure; after pressurizing the pressurization zone, transferring at least a portion of the cellulosic biomass from the pressurization zone to the digestion unit, which is at a third pressure that is less than or equal to the second pressure but higher than the first pressure; and digesting at least a portion of the cellulosic biomass in the digestion unit to produce a hydrolysate comprising soluble carbohydrates.
摘要:
Biomass conversion systems may incorporate integrated heat management to operate more efficiently during biomass conversion. Biomass conversion systems may comprise a first fluid circulation loop comprising a hydrothermal digestion unit, and a first catalytic reduction reactor unit in fluid communication with an inlet and an outlet of the hydrothermal digestion unit; and a second fluid circulation loop comprising a reaction product take-off line in fluid communication with the first fluid circulation loop, a second catalytic reduction reactor unit in fluid communication with the reaction product take-off line, and a recycle line establishing fluid communication between the first fluid circulation loop and an outlet of the second catalytic reduction reactor unit, where the first catalytic reduction reactor unit contains at least one first catalyst and the second catalytic reduction reactor unit contains at least one second catalyst, each being capable of activating molecular hydrogen.
摘要:
A process for producing biofuels from biomass is provided by removing sulfur compounds and nitrogen compounds from the biomass by contacting the biomass with a digestive solvent to form a pretreated biomass containing soluble carbohydrates and having less than 35% of the sulfur content and less than 35% of the nitrogen content, based on untreated biomass on a dry mass basis, prior to carrying out aqueous phase reforming and further processing to form a liquid fuel.
摘要:
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.
摘要:
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.
摘要:
The invention provides a process for preparing 1,3-alkanediols, such as 1,3-propanediol (PDO), from 3-hydroxyaldehydes, such as 3-hydroxypropanal (HPA), comprising providing a mixture of 3-hydroxyaldehydes in an organic solvent; extracting into an aqueous liquid a major portion of the 3-hydroxyaldehydes to provide an aqueous phase comprising 3-hydroxyaldehydes in greater concentration than the concentration of 3-hydroxyaldehydes in the 3-hydroxyaldehyde mixture, and an organic phase; separating the aqueous phase from the organic phase; contacting the aqueous phase with hydrogen in the presence of a hydrogenation catalyst to provide a hydrogenation product mixture comprising 1,3-alkanediols and water; separating water from the 1,3-alkanediols using a multi-effect evaporation scheme; recycling water containing about 50 wt % or less 1,3-propanediol based upon the total amount of 1,3-propanediol and water to the extraction stage; and recovering 1,3-alkanediols.
摘要:
A process for producing 1,3-propanediol comprising the steps of: a) forming an aqueous solution of 3-hydroxypropanal, b) hydrogenating the 3-hydroxypropanal to form a first crude 1,3-propanediol mixture comprising 1,3-propanediol, water, and MW 132 cyclic acetal, c) distilling the first crude 1,3-propanediol mixture to remove water and low boiling impurities and form a second crude 1,3-propanediol mixture, d) contacting the second crude 1,3-propanediol mixture with a solid acid purifier at a temperature of from about 50 to about 250° C. to convert the MW 132 cyclic acetal to more volatile cyclic acetals, and e) separating the more volatile cyclic acetals from the 1,3-propanediol by distillation or gas stripping.
摘要:
Disclosed is a one step hydroformylation process for preparing a 1,3-diol, comprising the reaction of an oxirane with syngas at hydroformylation conditions in an inert solvent in the presence of a hydroformylation catalyst comprising a ruthenium (+1)-phosphine bidentate: cobalt (−1) complex, wherein the ligated metal is ruthenium, under conditions which preferably upon completion of the oxirane/syngas reaction cause a phase separation of the reaction mixture into a solvent phase which is rich in catalyst and a second phase which is rich in the 1,3-diol, recycling the phase rich in catalyst directly to the hydroformylation reaction for further reaction with previously unreacted starting materials, thus permitting valuable hydroformylation catalyst to be recycled without degradation or exposure to downstream processing and recovering the 1,3-diol from the second phase rich in 1,3-diol.
摘要:
The invention provides a process for an improved oxirane hydroformylation catalyst, the improved oxirane hydroformylation catalyst, and a one step process for preparing a 1,3-diol in the presence of such a catalyst. One process for preparing the hydroformylation catalyst involves: a) forming a complex (A) by contacting a ruthenium(0) compound with a ditertiary phosphine ligand; and b) forming a complex (B) by subjecting complex (A) to a redox reaction with a cobalt(0) carbonyl compound. This catalyst is used in a one step hydroformylation process for preparing a 1,3-diol, comprising the reaction of an oxirane with syngas at hydroformylation conditions in an inert solvent in the presence of the above hydroformylation catalyst where recovery of product is preferably accomplished via phase separation of a diol rich phase from the bulk reaction liquor.