Kinetics and Thermodynamics of Silk Dyeing with Turmeric Extract
A kinetics and thermodynamics study of turmeric extract dyeing on Bombyx mori silk fabric was conducted with 1 g/L initial dye concentration at three temperatures (70 °C, 85 °C, and 100 °C). The fabric was pre-mordanted with FeSO4 and dyed with the turmeric extract at pH 7 and a material liquor ratio (MLR) of 1:20. Pseudo first-order and pseudo second-order kinetics were tested. The adsorption kinetics of turmeric extract dyeing on silk fit the pseudo second-order kinetic model. The activation energy was 94.9 kJ/mol. The enthalpy and entropy of activation were 91.93 kJ/mol and –14.47 J/mol·K, respectively.