Oxygen-enriched Nanobubbles for a Green Reactive Washing Process

In this study, we used the new nanobubbles technology to create a green reactive washing process for the textile industry, as one of the most polluting sectors where environmentally friendly process designs are indispensable to protect the environment. With this technology, the possibility of eliminating the soaping-off step from the reactive washing sequence was investigated. For the design of an environmentally friendly reactive washing process, the effects of increasing the process temperature of the soaping-off step as well as the use of oxygen-enriched NBs in all washing steps after reactive dyeing with three different dyes were investigated. The results were evaluated by comparing the color coordinates, strength, and fastness of dyed cotton towels washed according to the conventional and alternative processes as well as examining the absorbance and chemical oxygen demand values of the washing baths. Alternative washings did not cause significant differences in color coordinates, while the lowest color strength and highest fastness values were obtained after washing with nanobubbles. The absorbance graphs showed that the most colorful baths belonged to the first bath of the nanobubble washing regime. Chemical oxygen demand measurements revealed that the alternative washing systems were more environmentally friendly than the conventional ones. Based on the results of this study, we concluded that it was possible to implement more eco-friendly washing methods by eliminating the use of soap. Graphical abstract