Lignin-Containing Cellulose Acetate Films from Grapevine Waste: A Sustainable Path to Compostable Bioplastics

Area of Science:

• Biomass valorization
• Green chemistry
• Sustainable materials science

Background:

• Grapevine shoots are abundant agricultural waste rich in cellulose and lignin.
• Valorizing this residue can reduce waste and reliance on fossil-based materials.
• Existing biorefinery processes may involve harsh chemicals or inefficient recovery.

Purpose of the Study:

• To develop an eco-friendly biorefinery process for grapevine shoots.
• To produce biodegradable films from cellulose and lignin.
• To evaluate the compostability and performance of the resulting bioplastics.

Main Methods:

• Autoclave-assisted pretreatment and organosolv extraction for cellulose and lignin recovery.
• Sulfur-free and chlorine-free processing steps.
• Acetylation of cellulose and plasticization with glycerol to form films.
• Home composting disintegration tests and comparison with commercial cellulose acetate.

Main Results:

• Successful co-recovery of cellulose and lignin under mild conditions.
• Lignin retained in cellulose provided antioxidant and UV-shielding properties.
• Biodegradable films produced exhibited full disintegration within 8 weeks of home composting.
• The developed bioplastics outperformed commercial cellulose acetate in compostability.

Conclusions:

• The biorefinery process offers a sustainable route for valorizing grapevine waste.
• Incorporating lignin enhances the functionality of cellulose-based materials.
• The resulting biodegradable films align with circular economy principles and green chemistry.