Fast fashion—affordable clothing that tends to be tossed after only a handful of wears—takes a hefty environmental toll. Growing cotton, for example, requires copious amounts of water and pesticides. And in the landfill, textiles release greenhouse gases as they degrade. What’s more, many of today’s clothes are made of difficult-to-recycle fabric blends.

Now chemical engineers in Finland have devised a way to break down cotton-polyester-blend fabrics and reuse some of the material. They presented their research at a recent meeting of the American Chemical Society. Using an ionic liquid (i.e., a liquid salt), they can dissolve or “melt” the cotton out of the fabric. The resulting cellulose solution can then be spun into new fibers.

Next, the team is investigating whether it can turn the recovered polyester into usable fibers and reuse dyes from the old clothes.