Dissolving Kraft Pulp Production and Xylooligosaccharide Coproduction: Effect of Pre-Hydrolysis Conditions

Area of Science:

• Biomass processing
• Sustainable materials science
• Chemical engineering

Background:

• Cotton's sustainability challenges drive the use of lignocellulosic materials for dissolving pulp.
• Pre-hydrolysis kraft is a key process, but conventional methods result in low-value byproducts like xylose and furfural.
• Xylooligosaccharides (XOS) are valuable specialty products derived from hemicelluloses but require specific recovery conditions.

Purpose of the Study:

• To recover xylooligosaccharides (XOS) during dissolving pulp production.
• To evaluate the impact of modified pre-hydrolysis conditions on XOS recovery and final pulp characteristics.

Main Methods:

• Utilized a flow-through reactor (FTR) for pre-hydrolysis to control xylan retention time in the extracted liquor.
• Investigated the effect of varying fluid retention times on the pre-hydrolysis process.

Main Results:

• Adjusting fluid retention time in the FTR significantly altered the recovery ratio of XOS, xylose, and furfural.
• Hemicellulose content in the dissolving pulp was substantially reduced from 6.8% to approximately 2.6% via FTR pretreatment.

Conclusions:

• Optimized pre-hydrolysis using an FTR enables efficient recovery of XOS.
• This method enhances the sustainability of dissolving pulp production by valorizing hemicelluloses and reducing waste.