Converting textile waste into value-added chemicals: An integrated bio-refinery process.

Area of Science:

• Biotechnology
• Chemical Engineering
• Environmental Science

Background:

• Textile waste generation is a growing global environmental concern.
• Valorization of textile waste into chemicals can mitigate environmental impact and create economic value.

Purpose of the Study:

• To investigate the conversion of various textile wastes (cotton, colored cotton, cotton-PET blends) into value-added chemicals.
• To develop effective pretreatment methods to enhance enzymatic hydrolysis efficiency for different textile waste types.
• To assess the potential of an integrated biorefinery process for textile waste valorization.

Main Methods:

• Enzymatic hydrolysis and fermentation/hydrogenation were employed for chemical conversion.
• Pretreatment methods included NaOH, HPAC-NaOH, and NaOH-ethanol.
• Analysis of glucose yield, sugar content, and final chemical yields (bioethanol, sorbitol, lactic acid, terephthalic acid, ethylene glycol).

Main Results:

• High glucose yield (99.1%) from white cotton waste after NaOH pretreatment.
• Improved cellulose digestibility (1.38-1.75 times) in colored cotton waste after HPAC-NaOH pretreatment.
• Efficient hydrolysis of cotton-PET blends (92.49% glucose yield) after PET removal.
• Maximum ethanol yield of 537 mL/kg from white T-shirt waste, outperforming lignocellulosic biomass.
• Selective conversion of glucose to sorbitol (70% yield) and lactic acid (83.67% yield).
• Terephthalic acid and ethylene glycol produced from cotton-PET blends.

Conclusions:

• Effective pretreatment strategies enable efficient enzymatic hydrolysis of diverse textile wastes.
• The integrated biorefinery process successfully converts textile waste into multiple high-value chemicals.
• This approach offers a sustainable solution for textile waste valorization, reducing environmental burden.