Reverse engineering for textiles : determining their composition is essential to support recycling processes

Textile recycling is an essential initiative to reduce waste and mitigate the environmental impact of the fashion industry. The process involves the collection of used garments, which are then sorted, cleaned and converted into new materials or repurposed products. Despite its potential, less than 1% of textile waste is currently recycled, due to the materials’ complexity (mix of natural and synthetic fibers) and lack of adequate characterization. Therefore, precise determination of the nature and quantity of the involved materials (synthetic and natural) is crucial to support the development of recycling processes. The aim of this thesis is to develop an automated prefractionation method based on liquid-liquid separation for the fibers most commonly found in textile waste, namely cotton, polyester, nylon, and elastane, with the ultimate goal of performing qualitative and quantitative characterization. Dissolving the polymers that make up these textile fibers presents a significant challenge, as each type of fiber requires specific solvents for effective dissolution. The dissolution conditions, such as temperature, pressure, and polymer-solvent ratio, must be carefully controlled to ensure complete dissolution. Theoretical tools such as Hansen solubility parameters, implicit solvation models, and screening models will be used for solvent selection. The extraction protocol will first be developed using model fiber mixtures before being applied to industrial textile waste. The resulting fractions will be characterized using conventional polymer analysis methods, including thermal and thermogravimetric analyses, as well as spectroscopic and chromatographic techniques.

Keywords: Textile recycling, Polymers, Centrifugal Partition Chromatography, Analysis

• Academic supervisor    PhD. A. CHAUMONNOT, IFPEN
• Doctoral School    ED206 Chimie, Procédé, Environnement, Université Lyon
• IFPEN supervisor    PhD. A. LE MASLE, ORCID : 0000-0002-1163-1233
• PhD location    IFPEN Lyon, FRANCE
• Duration and start date    3 years, starting in the fourth quarter 2025 (Novembre 3)
• Employer    IFPEN
• Academic requirements    University Master degree in analytical sciences   
• Language requirements    English level B2 (CEFR) 
• Other requirements    Polymer chemistry, strong taste for experimentation.

To apply, please send your cover letter and CV to the IFPEN supervisor indicated here below.