Eco-friendly Dyeing of Wool with Black Rice Extract and Investigation of the Adsorption Kinetics

Abstract

This work used the dye extracted from black rice for the preparation of ecological and functional textiles, also the dyeing property was investigated with different pH (2.0 to 8.0), dyeing temperatures (50 °C to 90 °C), and dye concentrations (1 % to 9 % owf). Furthermore, the functionalities and the adsorption kinetics of black rice extract on wool were also explored. The results revealed that the material had excellent dyeing properties at 90 °C for 60 min, with a dye concentration of 5 % owf, a pH of 4.0, and the colorfastness was rated above 4. The inhibition rates of E. coli and S. aureus remained above 85.09 % and 85.78 % after 10 cycles of accelerated laundering, and the percentage of DPPH scavenging rate was over 80 %. Moreover, it was confirmed that the correlation coefficients (R²) of the pseudo-second-order model were higher than the pseudo-first-order model at various temperatures, and there was an increment in the adsorption quantities of black rice extract at equilibrium (q_e) with an increase in temperature.