Recycling textiles into reusable cotton, polyesters and silver
By Scott Jenkins |
Millions of tons of cotton-polyester-blend material that would normally be discarded in landfills could be recycled using a newly patented method for removing dyes from textiles, separating cotton from fabric blends, and depolymerizing polyesters.
The process, developed and demonstrated by BCD Group Inc. (Cincinnati, Ohio; Email: email@example.com), represents a departure from current fabric-recycling approaches, which often require high-temperatures, lengthy processing times and costly solvents. BCD’s process occurs at 90–120°C in 10–20 min. and employs low-cost, reusable reagents in a way that retains the strength of the cotton fibers (photo). The easy-to-operate process also uses non-toxic chemicals that can be reused. Conventional depolymerization methods cannot be used for separating cotton-polyester blends because the high temperatures and long process times destroy cotton fibers.
In the BCD process, fabric blends of cotton and polyethylene terephthalate (PET) are shredded, then treated in a common stirred-tank reactor, with base and a proprietary phase-transfer catalyst (PTC). The PTC cleaves the bonds of dyes, polyesters and other chemicals bonded to cotton. The solid cotton fiber is removed from the reactor after…