Kinetics and Thermodynamics Studies of Monascus Red Dyeing on Wool

Abstract

The mechanism of monascus red pigment dye on wool fiber was studied by analyzing of dyeing kinetics and thermodynamics. The results showed that the dyeing rate is quite high at the beginning of dyeing at 70°C-100°C.The diffusion coefficient rise while half-dyeing time decrease With the temperature rise. Its adsorption accords with the combination of Nernst and Langmuir adsorption model. Its enthalpy and entropy of dyeing was 15.21kJ/mol and 46.87J / (mol·K) respectively, which show that wool dyeing with monascus red is a endothermic process. This theoretical is useful to built dyeing process for wool fiber with monascus red.