KAUNAS – Researchers in Lithuania, claim to have developed a new multi-stage chemical-based technique to remove indigo and sulphur dyestuffs and then separate cotton and polyester fibres from denim fabrics, with recycled rates in the region of 96 per cent.

 

Using activated carbon to regenerate the spent leaching solutions, polyester was extracted from the solution by CO2 saturation of water, and cotton was liberated in solution using a switchable hydrophilic solvent.

The process is claimed to lower the carbon footprint of traditional methods of recycling denim waste and produce significant economic returns once extrapolated to a commercial scale.