Pilot-scale eco-friendly dyeing of natural fibers in supercritical carbon dioxide

Important results from the project

The main goal of the project was to test scalability of the new dyeing process that uses supercritical carbon dioxide as the dyeing medium. Successful dyeing tests on the bulk scale were run, analysis of the data performed, scaling issues were identified and suggestions how to resolve them were proposed. It was considered that the new process can be acceptable from techno-economical point of view, should the scaling issues be resolved in the future.

Expected long term effects

It was found that dyeing of natural fibers is possible in a larger scale equipment, however scaling up process is more complex than for synthetic fibers and may require considerable efforts and resources, possibly within both chemistry and engineering fields. In particular, color depth needs to be further improved before industrialization. Other process parameters may require only comparatively small adjustments, which is beneficial for compatibility with the existing installed dyeing equipment.

Approach and implementation

Supercritical carbon dioxide-based dyeing of natural fibers has good potential to replace traditional dyeing in water-scarce regions. However, further advancements of that technology require a set of expensive equipment and multidiscipline expertise to address scaling issues. Hence, establishing more partnerships and engaging more stakeholders will be required for successful implementation.