Without limitation, the disclosure provides processes for (a) dissolving biomass in ionic liquids, (b) deconstructing cellulose, hemicellulose and/or lignin into derivatives including fermentable sugars, (c) separating the biomass derivatives from the ionic liquid, and (d) converting the biomass derivatives to useful fuels or chemicals, either dissolved within or separated from the ionic liquid. It should be understood that processes described herein can be used in isolation or in combination with each other.

Without limitation, the disclosure provides processes for (a) dissolving biomass in ionic liquids, (b) deconstructing cellulose, hemicellulose and/or lignin into derivatives including fermentable sugars, (c) separating the biomass derivatives from the ionic liquid, and (d) converting the biomass derivatives to useful fuels or chemicals, either dissolved within or separated from the ionic liquid. It should be understood that processes described herein can be used in isolation or in combination with each other.

The invention relates to an improved process for separating lignin and monomeric sugars from a liquor comprising lignin and monomeric sugars in a solvent mixture of water and at least one organic solvent, which employs membrane filtration techniques such as nanofiltration and selective water removal, preferably by permeation through a membrane which is selective for water molecules. The invention further relates to a modular system for executing the process according to the invention. The process and system according to the invention are particularly suitable to be incorporated with pre-treatment of lignocellulosic biomass, in particular by organosolv fractionation or solvolysis.

The invention relates to an improved process for separating lignin and monomeric sugars from a liquor comprising lignin and monomeric sugars in a solvent mixture of water and at least one organic solvent, which employs membrane filtration techniques such as nanofiltration and selective water removal, preferably by permeation through a membrane which is selective for water molecules. The invention further relates to a modular system for executing the process according to the invention. The process and system according to the invention are particularly suitable to be incorporated with pre-treatment of lignocellulosic biomass, in particular by organosolv fractionation or solvolysis.

A method of producing a sugar liquid includes filtering a cellulose-derived sugar liquid through one or more separation membranes selected from the group consisting of an ultrafiltration membrane, a nanofiltration membrane and a reverse osmosis membrane, and washing the separation membrane(s) after filtration with washing water containing an acidic substance and an aromatic compound.

A method of producing a sugar liquid includes filtering a cellulose-derived sugar liquid through one or more separation membranes selected from the group consisting of an ultrafiltration membrane, a nanofiltration membrane and a reverse osmosis membrane, and washing the separation membrane(s) after filtration with washing water containing an acidic substance and an aromatic compound.

Methods for processing a lignocellulosic biomass are provided and include the steps of: combining the lignocellulosic biomass with a hydrophobic deep eutectic solvent (HDES); heating a mixture including the lignocellulosic biomass and the HDES; and separating the mixture into a HDES phase including a first constituent of the lignocellulosic biomass, an aqueous phase including a second constituent of the lignocellulosic biomass, and a solid-residue phase including a third constituent of the lignocellulosic biomass. Water is added to the combination of the lignocellulosic biomass and the HDES, either before or after heating. An acidic additive can be added prior to heating the mixture including the lignocellulosic biomass and the HDES, or a ternary HDES including an acidic compound can be utilized, to further promote dissolution of the lignocellulosic biomass prior to heating.

Methods for processing a lignocellulosic biomass are provided and include the steps of: combining the lignocellulosic biomass with a hydrophobic deep eutectic solvent (HDES); heating a mixture including the lignocellulosic biomass and the HDES; and separating the mixture into a HDES phase including a first constituent of the lignocellulosic biomass, an aqueous phase including a second constituent of the lignocellulosic biomass, and a solid-residue phase including a third constituent of the lignocellulosic biomass. Water is added to the combination of the lignocellulosic biomass and the HDES, either before or after heating. An acidic additive can be added prior to heating the mixture including the lignocellulosic biomass and the HDES, or a ternary HDES including an acidic compound can be utilized, to further promote dissolution of the lignocellulosic biomass prior to heating.

The membrane bioreactor for simultaneous enzymatic cellulose hydrolysis and product separation is a vessel having a lower hydrolysis reaction chamber and an upper distilled water chamber separated by a semipermeable membrane attached to the top of the lower reaction chamber. The membrane is supported on a stainless steel mesh and sealed to the mesh by epoxy glue to prevent leakage. A peristaltic pump is connected to the reaction chamber and maintains a flow of distilled water through the membrane and the upper chamber, the effluent being collected in a beaker or other product collection vessel. The reaction chamber is agitated at a moderate rate by a magnetic stirrer, and the upper chamber is agitated more rigorously by a mechanical stirrer. A thermocouple and temperature controller and a buffer solution, respectively, maintain temperature and pH in the reaction chamber optimal for enzymatic hydrolysis of cellulose.

The membrane bioreactor for simultaneous enzymatic cellulose hydrolysis and product separation is a vessel having a lower hydrolysis reaction chamber and an upper distilled water chamber separated by a semipermeable membrane attached to the top of the lower reaction chamber. The membrane is supported on a stainless steel mesh and sealed to the mesh by epoxy glue to prevent leakage. A peristaltic pump is connected to the reaction chamber and maintains a flow of distilled water through the membrane and the upper chamber, the effluent being collected in a beaker or other product collection vessel. The reaction chamber is agitated at a moderate rate by a magnetic stirrer, and the upper chamber is agitated more rigorously by a mechanical stirrer. A thermocouple and temperature controller and a buffer solution, respectively, maintain temperature and pH in the reaction chamber optimal for enzymatic hydrolysis of cellulose.