Textile Recycling's Hidden Problem: Surface-Modified Fiber Fragments Emitted at Every Stage

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Sustainable textile waste management relies on chemical recycling.
• Recycling synthetic and blended textiles can release microplastic fibers (MPFs).
• Understanding MPF release during chemical recycling is crucial for environmental protection.

Purpose of the Study:

• To investigate microplastic fiber (MPF) release during acid and alkaline hydrolysis of polyester/cotton blended textiles.
• To compare MPF generation across different recycling stages (dye removal, treatment, product).
• To identify factors influencing MPF release and evaluate the effectiveness of different recycling approaches.

Main Methods:

• Investigated MPF release in acid and alkaline hydrolysis of polyester/cotton textiles.
• Analyzed MPF counts at various recycling stages: dye removal, treatment, and final product.
• Utilized statistical analysis (p-values) and ridge regression to identify key factors affecting MPF release.
• Performed surface characterization to observe treatment-induced fiber alterations.

Main Results:

• Dye removal generated the highest MPF counts (approx. 10,055 MPFs g^-1).
• Alkaline hydrolysis reduced MPF release by 87.55% during the treatment stage compared to acid hydrolysis.
• Recycling approach significantly impacted MPF release (p < 0.05), while fabric type did not (p > 0.05).
• Reaction conditions and blend ratios were identified as key factors in MPF fragmentation.

Conclusions:

• Chemical recycling of textiles, particularly polyester/cotton blends, is a significant source of MPF release.
• Alkaline hydrolysis is a more effective method for minimizing MPF emissions during the treatment stage compared to acid hydrolysis.
• Optimizing reaction conditions and exploring PET degradation/dissolution can further reduce MPF pollution from textile recycling.