Optimization of wool dyeing with rutin as natural dye by central composite design method

In this study, affected conditions for wool dyeing with rutin as a natural dye were optimized by exhaustion quantities with one-factor-at-a-time (OFT) method and the extracted results were used to further optimize its dyeing conditions by central composite design (CCD). The CCD was applied to design experiments for the evaluation of the interactive effects of the four most important operating variables namely temperature, NaCl quantity, pH and time. Moreover, this method decreased the required number of experiments. The values of the optimized factors for OFT and CCD, in wool dyeing with rutin were respectively as follows: temperature 70 °C and 70.24 °C, NaCl quantity 1.0 g and 1.50 g, pH 5.0 and 5.53, and time 80.0 min and 60.0 min. The results predicted by CCD were found to be in good agreement (R2 = 99.08%) with those obtained by performing experiments. Finally, the obtained results showed a good wash fastness for dyed wool with rutin.

► Rutin as a natural dye belongs to flavonoid families which play a significant biological role in plant pigmentation and possess anti-cancer and anti-viral properties.
► Rutin has been used for dyeing wool for the first time.
► In order the dyeing to be environmental friendly, metal mordants were not used and dyeing condition was set to give dyed sample good washing fastness.
► Central Composite Design was used to optimize the dyeing condition which can considers all effective factors at the same time.