Towards polycotton waste valorisation: depolymerisation of cotton to glucose with polyester preservation

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Textile waste, primarily polycotton (cotton and polyester), is a significant environmental burden, with most ending in landfills or incineration.
• Current textile recycling rates are low, and most recycling involves downcycling, yielding lower-value products.
• There is a critical need to shift from fossil-based feedstocks to sustainable, bio-based alternatives.

Purpose of the Study:

• To review current methods for hydrolyzing cotton into glucose from polycotton textile waste.
• To assess techniques that preserve the polyester component during cotton hydrolysis.
• To facilitate the valorization and reuse of both cotton and polyester fractions from textiles.

Main Methods:

• Acid hydrolysis of cotton cellulose.
• Enzymatic hydrolysis of cotton cellulose.
• Combined acid and enzymatic hydrolysis approaches.
• Focus on preserving the poly(ethylene terephthalate) (PET) component.

Main Results:

• Successful hydrolysis of cotton into glucose is achievable through various methods.
• Preservation of the polyester component during cotton hydrolysis is feasible.
• Separation of glucose and PET enables individual valorization.

Conclusions:

• Hydrolysis of cotton-rich textiles offers a sustainable route to glucose, a valuable chemical feedstock.
• Effective separation of cotton and polyester components allows for the circular reuse of textile materials.
• These methods support the transition to a bio-based economy and reduce reliance on fossil fuels.