When you throw your old black T-shirt or washed-out jeans into the old clothes container, you usually think: It will be recycled. But the reality is different. Of the 12.6 million tons of textile waste generated in the EU every year, just 22 percent is reused or recycled. The rest ends up in waste incineration or landfill. As of this year, this is no longer permitted. The EU stipulates that used textiles must be collected separately and recycled. But there is a problem with this.
Modern sorting systems work with near-infrared technology, similar to the yellow garbage can. The machines recognize cotton, polyester or polyamide and sort the fabrics automatically. However, the technology fails with black textiles. Especially if they have been dyed with soot, they hardly reflect any light in the infrared range. The sorting machine remains blind. Elastic garments also cause difficulties. Just one to three percent elastane in a pair of jeans is enough to disrupt many recycling processes. The material can no longer be dyed after production and therefore has to be sorted out. However, the tiny quantities are barely detectable with today's technology.
Leipzig researchers develop new sorting processes
This is where the European research project SORT4CIRC comes in, which was launched at the beginning of December 2025. Scientists from the Leibniz Institute for Surface Modification (IOM) in Leipzig are involved. Dr. Tom Scherzer and Dr. Olesya Daikos are working on the further development of hyperspectral cameras. A total of 15 partners from eight European countries are jointly researching solutions. The EU is funding the project with five million euros over three years. The researchers want to develop new analytical methods that can also detect black and coated textiles as well as clothing with elastane.
Artificial intelligence to detect tiny quantities
The scientists are relying on innovative techniques that have not previously been used in the sorting of textile waste. Artificial intelligence will help to reliably detect even the smallest components such as elastane. At the end of the project, the researchers are planning a demonstrator plant. This should combine various analytical processes and be able to sort textiles fully automatically. Regardless of color or additives. The sorted materials could then be efficiently recycled. In the best case scenario, new items of clothing are created from them. This would turn old textiles into new fashion again.
