Monosaccharide production in an acid sulfite process: kinetic modeling

Area of Science:

• Biorefinery Processes
• Chemical Engineering
• Wood Chemistry

Background:

• Spent sulfite liquor (SSL) is a lignocellulosic byproduct of sulfite pulping.
• SSL contains sugars and lignosulfonates, offering potential for value-added products.
• Utilizing SSL sugars aligns with biorefinery principles for sustainable resource management.

Purpose of the Study:

• Investigate the kinetic modeling of carbohydrate degradation in SSL.
• Determine optimal conditions for sugar conversion within a biorefinery context.
• Evaluate the impact of temperature on sugar degradation and byproduct formation.

Main Methods:

• Laboratory-scale reactors were used to simulate the sulfite pulping process.
• Kinetic parameters for carbohydrate degradation were determined at 130, 140, and 150 °C.
• Aspen Custom Modeler was employed to analyze reaction kinetics using first and n-order models.

Main Results:

• The optimal temperature for maximizing sugar conversion in SSL was identified as 130 °C.
• At 130 °C, a maximum sugar conversion of 33.91 mol% was achieved.
• Decomposition products were minimized at 130 °C, reaching 13.81 mol%.

Conclusions:

• Kinetic modeling provides crucial insights for optimizing SSL utilization in biorefineries.
• 130 °C is the preferred temperature for maximizing monosaccharide recovery and minimizing unwanted degradation.
• This research supports the sustainable valorization of lignocellulosic waste streams.