Efficient catalytic conversion of microalgae residue solid waste into lactic acid over a Fe-Sn-Beta catalyst.

Area of Science:

• Catalysis
• Biomass Conversion
• Green Chemistry

Background:

• Microalgae residue is an abundant, underutilized resource.
• Lactic acid is a valuable platform chemical with diverse applications.
• Efficient conversion of biomass to chemicals is crucial for sustainable industry.

Purpose of the Study:

• To investigate the catalytic conversion of microalgae residue into lactic acid.
• To elucidate the reaction mechanism and identify key factors influencing lactic acid yield.
• To evaluate the role of different microalgae components (lipids, proteins, carbohydrates) in the process.

Main Methods:

• Utilized a Fe-Sn-Beta heterogeneous catalyst for lactic acid production.
• Conducted reactions under mild conditions (210 °C, 2 hours).
• Analyzed reaction intermediates and products using chemical and spectroscopic methods.

Main Results:

• Achieved a high lactic acid yield of 33.9% from microalgae residue.
• Identified hydrolysis, isomerization, and retro-aldol condensation as key reaction steps.
• Demonstrated that lipids inhibit lactic acid production by deactivating catalyst sites.
• Showed that proteins enhance production by buffering monosaccharide release and maintaining catalyst activity.

Conclusions:

• Microalgae residue is a promising feedstock for lactic acid production.
• The Fe-Sn-Beta catalyst enables efficient conversion under mild conditions.
• Understanding the roles of lipids and proteins is key to optimizing microalgae valorization.