Patent classifications
C13B20/146
Separation and recovery of xylose using weakly basic anion exchange resins
The invention relates to a method of separating and recovering xylose from a xylose-containing plant-based solution. The method is performed in a chromatographic separation system, which comprises one or more weak base anion exchange resins and optionally one or more other resins selected from strong acid cation exchange resins and weak acid cation exchange resins, by passing the solution through the separation system, followed by recovering at least one fraction enriched in xylose. Optionally, a rhamnose fraction may also be recovered.
REGENERATION OF WEAK BASE ANION EXCHANGE RESINS
The present invention relates generally to regeneration of weak base anion exchange resins and more particularly to regeneration using low concentrations of sodium hydroxide and/or sodium carbonate to remove ionic contaminants from the resins.
Method for Bleaching Sugar With Effluent Recycling
The invention relates to a method for treating sugar comprising: placing a coloured sugar juice in contact with an ion exchange resin so as to charge the resin with colouring agents and to collect a bleached sugar juice; regenerating the colouring-charged resin, comprising: placing the charged resin in contact with a regeneration brine comprising a chloride salt; and collecting a regeneration effluent, the regeneration effluent comprising at least three fractions A, B and C, fraction A having a higher concentration of chloride salt than fractions B and C; and recycling the regeneration effluent, comprising: nanofiltration of fraction A of the regeneration effluent in order to obtain a first permeate and a first retentate; diafiltration of the first retentate, said diafiltration comprising: dilution of the first retentate with the fraction B of the regeneration effluent; nanofiltration of the mixture in order to obtain a second permeate and a second retentate; mixing of the first permeate with the second permeate and fraction C of the regeneration effluent,
Method for recovering an acid from acid/sugar solutions
Acid hydrolysis of biomass is an important step for releasing the component sugars before converting them to fuels and/or biochemicals. During such a process, a significant amount of mineral acid, such as sulfuric acid, is used. In most cases, the residual acid is neutralized with lime before the sugar conversion step. By doing so, a waste calcium sulphate stream is generated and sent to disposal. The efficient separation of acid from the sugars would allow the recycle of the acid and make the entire process more economically viable. We found that a resin bed packed with an acid retardation resin can be used to achieve an efficient separation (i.e. 98.5% recovery of the acid) of the sulfuric acid from the sugars. The resin bed can be simply regenerated with water.