Production of renewable hexanols from mechanocatalytically depolymerized cellulose by using Ir-ReOx /SiO2 catalyst

Area of Science:

• Catalysis
• Biomass Conversion
• Green Chemistry

Background:

• Cellulose, a renewable biopolymer, presents a challenge for efficient conversion into valuable chemicals.
• Developing sustainable catalytic processes for biomass valorization is crucial for a circular economy.

Purpose of the Study:

• To investigate the high-yield production of hexanols from cellulose.
• To optimize reaction conditions for cellulose conversion using a specific catalyst system.

Main Methods:

• Cellulose depolymerization via mechanocatalysis with sulfuric acid (H2SO4).
• Catalytic conversion of cellulose derivatives to hexanols using an Iridium-Rhenium oxide on silica (Ir-ReOx/SiO2) catalyst.
• Utilizing a biphasic reaction system (n-decane + water) to extract products.

Main Results:

• Achieved a high yield of 60% for hexanols from cellulose conversion.
• Identified optimal conditions: n-decane/water ratio ~2 (v/v), 413 K, 10 MPa H2, for 24 hours.
• Demonstrated the critical role of mechanocatalytic depolymerization and sufficient n-decane in hexanol production.

Conclusions:

• The Ir-ReOx/SiO2 catalyst, combined with mechanocatalytic cellulose depolymerization and a biphasic system, enables efficient hexanol synthesis.
• Sulfuric acid plays a dual role in cellulose hydrolysis and enhancing catalyst activity.
• The biphasic system effectively extracts hexanols and prevents further degradation.