Introducing hydroxyl groups as cellulose-binding sites into polymeric solid acids to improve their catalytic...

Area of Science:

• Catalysis
• Materials Science
• Biomass Conversion

Background:

• Cellulose hydrolysis to glucose is vital for producing biofuels and chemicals from lignocellulosic biomass.
• Solid acids present a sustainable alternative to traditional cellulases and homogeneous acids for cellulose hydrolysis.

Purpose of the Study:

• To fabricate novel porous polymeric solid acids with hydroxyl and sulfonic acid groups for efficient cellulose hydrolysis in water.
• To investigate the catalytic performance and structural properties of these synthesized bifunctional solid acids.

Main Methods:

• Fabrication of porous polymeric solid acids via Friedel-Crafts polymerization of hydroxyl-containing aromatic monomers followed by sulfonation.
• Hydrolysis of microcrystalline cellulose (Avicel) and ball-milled Avicel using the synthesized solid acids at 120 °C.

Main Results:

• The synthesized bifunctional solid acids achieved 93% hydrolysis of Avicel to glucose within 48 hours at 120 °C.
• Complete hydrolysis (98%) of ball-milled Avicel was achieved within 24 hours at 120 °C.
• High catalytic performance was attributed to the porous structure (large surface area) and the presence of hydroxyl groups for cellulose binding.

Conclusions:

• Porous polymeric solid acids with dual hydroxyl and sulfonic acid functionalities are highly effective catalysts for cellulose hydrolysis.
• These solid acids offer a promising, efficient, and potentially low-cost route for converting lignocellulosic biomass into valuable glucose.
• The combination of a porous structure and cellulose-binding hydroxyl groups is key to the superior catalytic activity observed.