Patent ID: 8287652

Claim:
A process of recovering xylose by nanofiltration from a solution of plant-based biomass hydrolysate containing xylose, comprising subjecting the solution to nanofiltration to obtain a nanofiltration retentate and a nanofiltration permeate, and recovering the nanofiltration permeate comprising a solution enriched in xylose, further comprising regulating xylose flux in the nanofiltration permeate to a range of 0.2 to 3 kg xylose/(m 2 /h), whereby the xylose flux refers to the amount of xylose (kg) that permeates through the nanofiltration membrane during one hour calculated per one square meter of the membrane surface and is determined by measuring the flow (solution flux) and the content of the dry substance and xylose in the permeate, by adjusting dry substance content (DS) of the solution of the plant-based biomass hydrolysate used as a nanofiltration feed to a range of 25-35% by weight and the xylose content of the nanofiltration feed to a range of 35-50% on DS, and by further adjusting the nanofiltration temperature to the range of 55-70Â° C. and the nanofiltration pressure to the range of 30-40 bar, and recovering a nanofiltration permeate having a dry substance content of 5 to 40% by weight and a xylose content of 35 to 85% on DS, to provide a xylose enrichment factor of at least 1.2 in the nanofiltration permeate, a permeate dilution factor higher than 0.2 and a xylose yield of more than 60% on xylose in the nanofiltration feed.