Physicochemical Behavior of Superfine Wool Powder Dyed with Reactive Dye

Abstract

Superfine wool powder is obtained from waste wool fiber by physical grinding. Its physicochemical properties are different from those of wool fiber, and it is widely used in industry. In order to clarify the dyeing behavior of wool powder, C. I. Reactive Yellow 145 dye was used to dye wool powder, and the adsorption kinetics and thermodynamics were systematically studied in this work. The adsorption kinetics of reactive dye on wool powder was found to adhere to a pseudo-second-order kinetic model. At 60, 80 and 95°C, the half-dyeing time (t1/2) and diffusion coefficient were 2.37, 1.56 and 1.00 min, and 0.2045, 0.1611 and 0.1368 cm2·min−1, respectively. And the diffusion activation energy was −11.82 kJ·mol−1. A Langmuir-type adsorption isotherm was obtained. At 60, 80 and 95°C, the standard affinity was 18.17, 20.06 and 20.82 kJ·mol−1, respectively. And the dyeing enthalpy change and dyeing entropy change were 7.27 kJ·mol−1 and 0.077 kJ·mol−1·K−1, respectively. In addition, the specific surface area, morphology and dyeing properties of wool fiber were compared. Through the study on the dyeing physicochemical properties of wool powder, it provides a theoretical basis for people to understand and use wool powder.

Keywords

• wool powder
• dyeing
• adsorption kinetics
• thermodynamics
• specific surface area
• physicochemical behavior