Waterless Dyeing in the Textile Industry
Textile Insights and Future Aspects, NOVA Publications , ss.95-112, 2024
- Yayın Türü: Kitapta Bölüm / Araştırma Kitabı
- Basım Tarihi: 2024
- Yayınevi: NOVA Publications
- Sayfa Sayıları: ss.95-112
- Anahtar Kelimeler: Eco-friendly dyeing, Supercritic carbon dioxide, Waterless dyeing
- Uşak Üniversitesi Adresli: Evet
Özet
Due to the release of chemicals into the environment, environmental concerns reaching the highest levels, the necessity of reducing waste, and the desire to maximize efficiency bring more environmentally friendly approaches to the fore. In the textile dyeing sector, which causes intense freshwater consumption and wastewater problems, studies on waterless dyeing have increased in recent years. In terms of sustainability, it is important that both carbon dioxide and waste dyestuff can be recycled. After dyeing without the use of water and solvents, the drying step is also eliminated, thus reducing energy consumption. Supercritical carbon dioxide (Sc-CO2) dyeing has the capacity to be a good alternative to conventional textile dyeing methods. In the case of successful commercialization of Sc- CO2 dyeing, it will be possible to reduce water use, eliminate discharges from wastewater, and economize in dyeing processes. At the same time, it is foreseen that shortening the processing time, reducing the chemicals used, energy consumption, and air emissions will increase production. In this study, studies on the use of supercritical Sc-CO2 in the textile industry, which started in the 1980s, and developments in its commercial application were evaluated. During the Sc-CO2 dyeing process, the solubility and equilibrium distribution of the dyes, mass transfer, and physicochemical events occurring during the coloring process are the studied aspects of this method. Although dyeing with this method has generally been successful in synthetic materials, its use in dyeing with natural fibers has also become a separate focus. The plasticizing effect of CO2 in glass and semi-crystalline polymers and, therefore, the change in the glassy region also causes changes in the morphology of semi-crystalline polymers such as textile fibers. Among the factors that are effective in dyeing with Sc-CO2 are the ability to dissolve dyes belonging to the dispersed dye group and the ability of hydrophobic polymers to reduce the glass temperature (Tg). It is promising in terms of natural dyeing that the extraction of pure natural dyestuffs by using Sc-CO2 in a shorter time and, at the same time, reduces the use of solvents. This study is an evaluation of environmentally friendly dyeings using Sc-CO2 until 2022.