Cotton waste processing into natural colorants

The textile industry faces a significant environmental challenge, annually generating 45 million tons of waste cotton textiles, of which 75% are incinerated or sent to landfills, causing environmental harm. Additionally, 67% of garments are made of plastic fibers, and when disposed of in landfills, 5% of them turn into microplastics that can end up on our plates. Chicfashic proposes an innovative biotech process to address these issues by recovering and recycling plastic fibers while transforming natural fibers into bio-based molecules. These molecules are then used as secondary raw materials to produce bio-based pigments for textiles. The project aims to optimize this process and test it on a larger scale with the assistance of HAN BioCentre. This initiative aligns with Dutch government and EU regulations mandating textile recycling by 2050. The technology used is patent pending and does not involve the use of toxic chemicals or the release of harmful wastewater or fumes, contributing to a shift towards a more circular and sustainable textile industry by reintegrating natural colorants into textile production.

Eindrapportage

In this project, we explored a sustainable solution for textile waste by transforming discarded cotton—such as old lab coats—into natural pigments that could be used in applications like textile dyeing. Our goal was to demonstrate the potential for creating circular products within the fashion and textile industry.

To achieve this, we first focused on breaking down the cotton material into simple sugars using enzymes. These enzymes were not only produced in our own laboratory but also scaled up to a 60-liter process. By applying a Design of Experiments (DoE) approach, we were able to optimize key conditions—such as pH, temperature, and reaction time—to enhance the activity of our lab-made enzymes.

With these sugars in hand, we moved to the next step: pigment production. We selected two specific fungi capable of converting sugars into colorful pigments. These fungi successfully produced pigments from the sugars derived from cotton waste.

Importantly, we managed to produce a batch of pigments from old lab coats, proving the concept works. However, we observed that pigment yields from textile waste were lower compared to using refined sugars, suggesting further optimization is needed.

Overall, our work shows that it's possible to turn cotton waste into valuable products, offering a promising step toward circular and more sustainable textile processes.